[House Hearing, 117 Congress]
[From the U.S. Government Publishing Office]
CLIMATE CHANGE AND THE U.S.
AGRICULTURE AND FORESTRY SECTORS
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HEARING
BEFORE THE
COMMITTEE ON AGRICULTURE
HOUSE OF REPRESENTATIVES
ONE HUNDRED SEVENTEENTH CONGRESS
FIRST SESSION
__________
FEBRUARY 25, 2021
__________
Serial No. 117-1
Printed for the use of the Committee on Agriculture
agriculture.house.gov
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
__________
U.S. GOVERNMENT PUBLISHING OFFICE
44-956 PDF WASHINGTON : 2021
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COMMITTEE ON AGRICULTURE
DAVID SCOTT, Georgia, Chairman
JIM COSTA, California GLENN THOMPSON, Pennsylvania,
JAMES P. McGOVERN, Massachusetts Ranking Minority Member
FILEMON VELA, Texas AUSTIN SCOTT, Georgia
ALMA S. ADAMS, North Carolina, Vice ERIC A. ``RICK'' CRAWFORD,
Chair Arkansas
ABIGAIL DAVIS SPANBERGER, Virginia SCOTT DesJARLAIS, Tennessee
JAHANA HAYES, Connecticut VICKY HARTZLER, Missouri
ANTONIO DELGADO, New York DOUG LaMALFA, California
BOBBY L. RUSH, Illinois RODNEY DAVIS, Illinois
CHELLIE PINGREE, Maine RICK W. ALLEN, Georgia
GREGORIO KILILI CAMACHO SABLAN, DAVID ROUZER, North Carolina
Northern Mariana Islands TRENT KELLY, Mississippi
ANN M. KUSTER, New Hampshire DON BACON, Nebraska
CHERI BUSTOS, Illinois DUSTY JOHNSON, South Dakota
SEAN PATRICK MALONEY, New York JAMES R. BAIRD, Indiana
STACEY E. PLASKETT, Virgin Islands JIM HAGEDORN, Minnesota
TOM O'HALLERAN, Arizona CHRIS JACOBS, New York
SALUD O. CARBAJAL, California TROY BALDERSON, Ohio
RO KHANNA, California MICHAEL CLOUD, Texas
AL LAWSON, Jr., Florida TRACEY MANN, Kansas
J. LUIS CORREA, California RANDY FEENSTRA, Iowa
ANGIE CRAIG, Minnesota MARY E. MILLER, Illinois
JOSH HARDER, California BARRY MOORE, Alabama
CYNTHIA AXNE, Iowa KAT CAMMACK, Florida
KIM SCHRIER, Washington MICHELLE FISCHBACH, Minnesota
JIMMY PANETTA, California ------
ANN KIRKPATRICK, Arizona
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______
Anne Simmons, Staff Director
Parish Braden, Minority Staff Director
C O N T E N T S
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Page
Bustos, Hon. Cheri, a Representative in Congress from Illinois,
submitted statement............................................ 383
Costa, Hon. Jim, a Representative in Congress from California,
prepared statement............................................. 6
Submitted letters on behalf of:
Mulhern, Jim, President and Chief Executive Officer,
National Milk Producers Federation..................... 329
Center for Food Safety, et al............................ 330
National Cattlemen's Beef Association, et al............. 332
Panetta, Hon. Jimmy, a Representative in Congress from
California, submitted letters.................................. 388
Pingree, Hon. Chellie, a Representative in Congress from Maine,
prepared statement............................................. 6
Submitted report............................................. 333
Schrier, Hon. Kim, a Representative in Congress from Washington,
submitted letter............................................... 387
Scott, Hon. David, a Representative in Congress from Georgia,
opening statement.............................................. 1
Prepared statement........................................... 2
Submitted articles........................................... 131
Submitted reports............................................ 214
Submitted letters on behalf of:
Hanson, Ph.D., Chad, Chief Scientist and Director;
Jennifer Mamola, D.C. Forest Protection Advocate, John
Muir Project........................................... 215
Linder, John, President, National Corn Growers
Association............................................ 220
Olson, Julia, Executive Director, Our Children's Trust... 223
Agricultural Retailers Association, et al................ 289
American Society of Agronomy, et al...................... 291
Biotechnology Innovation Organization.................... 295
Submitted statements on behalf of:
Glenn, Ph.D., Barbara P., Chief Executive Officer,
National Association of State Departments of
Agriculture............................................ 326
BASF Corporation......................................... 327
Thompson, Hon. Glenn, a Representative in Congress from
Pennsylvania, opening statement................................ 3
Witnesses
Cantore, Jim, Senior Meteorologist, The Weather Channel, Atlanta,
GA............................................................. 8
Prepared statement........................................... 9
Submitted questions.......................................... 393
Knox, Pamela N., Director, University of Georgia Weather Network;
Agricultural Climatologist, UGA Cooperative Extension, Athens,
GA............................................................. 11
Prepared statement........................................... 13
Submitted questions.......................................... 394
Duvall, Zippy, President, American Farm Bureau Federation,
Washington, D.C................................................ 23
Prepared statement........................................... 25
Submitted questions.......................................... 397
Brown, Gabe, Co-Owner/Operator, Brown's Ranch, Bismarck, ND...... 27
Prepared statement........................................... 29
Submitted questions.......................................... 399
Shellenberger, Michael D., Founder and President, Environmental
Progress, Berkeley, CA......................................... 43
Prepared statement........................................... 45
Submitted questions.......................................... 399
CLIMATE CHANGE AND THE U.S. AGRICULTURE AND FORESTRY SECTORS
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THURSDAY, FEBRUARY 25, 2021
House of Representatives,
Committee on Agriculture,
Washington, D.C.
The Committee met, pursuant to call, at 12:58 p.m., via
Webex, Hon. David Scott of Georgia [Chairman of the Committee]
presiding.
Members present: Representatives David Scott of Georgia,
Costa, McGovern, Adams, Spanberger, Hayes, Delgado, Rush,
Pingree, Kuster, Bustos, Plaskett, O'Halleran, Carbajal,
Lawson, Correa, Craig, Harder, Axne, Schrier, Panetta,
Thompson, Austin Scott of Georgia, Crawford, DesJarlais,
Hartzler, LaMalfa, Davis, Allen, Rouzer, Kelly, Bacon, Johnson,
Baird, Hagedorn, Jacobs, Balderson, Cloud, Mann, Feenstra,
Miller, Moore, Cammack, and Fischbach.
Staff present: Lyron Blum-Evitts, Melinda Cep, Ross
Hettervig, Prescott Martin III, Felix Muniz, Jr., Anne Simmons,
Ashley Smith, Anna Brightwell, Josh Maxwell, Ricki Schroeder,
Patricia Straughn, Erin Wilson, and Dana Sandman.
OPENING STATEMENT OF HON. DAVID SCOTT, A REPRESENTATIVE IN
CONGRESS FROM GEORGIA
The Chairman. This hearing of the Committee of Agriculture
entitled, Climate Change and the U.S. Agriculture and Forestry
Sectors, will now come to order.
I want to welcome and thank everyone for joining this most
important, timely, critical, and extraordinarily necessary
hearing today. After brief opening remarks, Members will
receive testimony from today's witnesses, and then the hearing
will be opened up to questions and discussions. Members will be
recognized in order of seniority, alternating between Majority
and Minority Members, and in order of arrival for those Members
who have joined us after the hearing was called to order. And
as normal, when you are recognized, you will be asked to unmute
your microphone, and will have 5 minutes to ask your questions
or make a statement. If you are not speaking, I will greatly
ask that you remain muted in order to minimize the background
noise. In order to get in as many questions as possible, the
timer will stay consistently visible on the screen to let you
know how much time you have.
And now, ladies and gentlemen, let me open this up with a
few remarks here myself.
This is perhaps the single-most important hearing that we
must have right now, because agriculture is our single-most
important industry overall, but especially right now, because
nobody: our farmers, our agriculture industry, they more than
any other entity or industry suffer more and benefit more from
climate and weather. And I say it is our most important
industry because of this: agriculture is the food we eat, it is
the water we drink, it is the clothes we wear, and it is our
shelter. Now, folks, we can do without a lot of things, but we
definitely can't do without food, water, clothing, the
necessities. And we have lost too many of our farms because we
moved too late to get the right information in about these
weather patterns. And so, I am so grateful for our Committee,
our staff, that has assembled a wonderful panel. I am so
thrilled to be able to approach this issue with my partner and
my friend, Ranking Member Thompson. This is critical.
And so, I just want us to move with this with an open heart
and an open mind, and to know that the American people are
watching us. It is agriculture that is at the point of the
spear when it comes to climate change. I am so grateful for the
talented Members of this Committee who are willing to take this
issue on and provide the critical leadership to deal with
climate change, to secure our food supply, and save our farms.
[The prepared statement of Mr. David Scott follows:]
Prepared Statement of Hon. David Scott, a Representative in Congress
from Georgia
Good morning, I'm excited to be here today for our first full
Committee hearing and in particular to begin work on what is without a
doubt the greatest challenge before us--climate change. I am also
excited for the opportunity to work with my colleague, Ranking Member
Thompson of Pennsylvania this Congress as he joins me in launching our
first hearing together.
The U.S. agriculture sector is amongst the most productive in the
world, contributing over $136 billion to the U.S. economy and directly
supporting 2.6 million jobs. The U.S. forestry sector is another
economic engine. In 2020, that sector manufactured $300 billion in
forest products and employed approximately 940,000 people.
Over the past century, long-term changes in weather patterns have
driven major changes across the globe, including the very landscapes
that support these sectors. Since 1880, the average global temperature
has increased about 2 F. Increased temperatures have accompanied
changes in rainfall patterns and more frequent climatic extremes. Most
recently, the National Oceanic and Atmospheric Administration declared
2020 as the second warmest year on record, after 2016.
These changes introduce significant risks to agricultural
production, forest resources, and the economy. These risks cannot be
understated. According to USDA's Economic Research Service, climate
change will likely affect risk-management tools, financial markets, and
our global food security, among other important areas.
Our farmers, ranchers, and forest managers understand these risks,
and they are the first to experience the pressures of a changing
climate. But American producers are resilient, and many are already
adopting production practices that not only improve productivity but
store carbon and reduce emissions in the atmosphere. And yet there is
tremendous opportunity to do more. It is incumbent on this Committee to
ensure producers have the financial and technical resources they need
to understand climate risks, consider mitigation strategies, and
receive the support they need to make important investments in their
operations.
I am excited to have such a broad range of witnesses to discuss
these points today. I am also eager to hear how we may improve upon
current policy and scale existing investments in proportion to the
magnitude of the challenge. I look forward to your testimony.
With that I would like to invite our Ranking Member, Mr. Thompson,
for any opening remarks.
The Chairman. With that, I want to turn it over to the
Ranking Member, the distinguished Member from Pennsylvania,
Ranking Member Thompson.
OPENING STATEMENT OF HON. GLENN THOMPSON, A REPRESENTATIVE IN
CONGRESS FROM PENNSYLVANIA
Mr. Thompson. Well, good afternoon everybody, and I would
like to thank the Chairman for holding today's hearing, and his
flexibility due to the updated floor schedule.
The impact that climate has on agriculture production and
on our natural resources is an issue of great importance to all
of us on the House Agriculture Committee. Working with us--and
Mr. Chairman, thank you for working with us on a mutually
agreeable time that provides for greater Member participation.
It is valued and very much appreciated. I would also like to
thank the witnesses who juggled their schedules to join us
today virtually, and I would like to thank all of our
constituents, the stakeholders who are joining us today
virtually as well.
Now, there is a saying I learned B.C. (Before Congress). If
you are not at the table, you are probably on the menu. And for
too long, the agriculture sector has been on the menu when it
comes to climate. The hearing today begins to pull us up to the
table.
I would like to start my remarks by making a very clear
position: the climate is changing. The Earth's temperature is
rising. I trust the science that globally industrial activity
has contributed to the issue. Reducing global emissions is what
we should be pursuing. It is the right thing to do, and it
requires smart, prudent, and science-based policies.
But the apocalyptic narrative of the world coming to an end
within a decade is not evidence-based and it is not supported
by science. The self-proclaimed experts who continue to spout
this impending doomsday scenario do nothing to advance the
climate solutions discourse. They only cause unnecessary public
angst and anxiety. It divides lawmakers when what we need is
collaboration.
I imagine these climate grifters must rely on scare tactics
to push their extreme agenda because it is burdensome,
overreaching, and negatively affects jobs and rural economies.
Not to mention the likelihood these policies could actually
result in higher global emissions, and I will touch more on
this in just a second.
Just over a decade ago, Congress rejected the Waxman-Markey
Cap and Trade, and for those who weren't around or need
reminding, this legislation was a national energy tax.
Estimates vary, but experts predicted under Cap and Trade
proposals, energy prices would increase as much as 125 percent.
It was predicted that this policy would have resulted in
American farm income dropping by $8 billion in 2012, $25
billion in 2024, and $50 billion in 2035. Decreases of 28, 60,
and 94 percent respectively. This underscores the most
troubling aspect of a national Cap and Trade system, or other
similar approaches, which is that 40 to 60 million acres of
land would likely have to shift from crop production and
planted to trees.
It is worth noting, largely due to the innovations in free
market principles, the United States has reduced emissions
comparable to, if not better than, what Waxman-Markey called
for in its out-year reduction targets.
Equally important, because it was not through government
prescriptive measures, energy costs on average have come down.
With Waxman-Markey energy prices would have skyrocketed. When
Waxman-Markey failed, the Obama EPA chose a different route and
pursued regulations to reduce emissions from the electricity
sector known as the Clean Power Plan. Fortunately, that was
stopped by the courts and eventually, the Trump EPA. Good
thing, too. The government prescriptive Obama Clean Power Plan
sought to reduce emissions 32 percent below 2005 levels by
2030. Without this regulation, and because of innovation and
the market, power sector emissions hit that 32 percent
reduction mark more than a decade sooner in 2019, without the
utility bill increases that would have come with the Clean
Power Plan.
Now, at a time when energy prices have decreased and
manufacturing has strengthened, United States has led the world
in reducing emissions. We have reduced carbon emissions more
than the next 12 emission-reducing nations combined.
Now, let me quote the head of the International Energy
Agency: `` . . . in the last 10 years, the emissions reductions
in the United States has been the largest in the history of
energy . . . This is a huge decline of emissions.'' \1\ Now,
the question isn't whether or not climate change is real; the
question is not whether or not to reduce emissions. The
question is how to best approach it?
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\1\ Editor's note: this quotation originates from the facebook
video feed, Secretary Perry Holds a Joint Press Conference with IEA
Executive Director Fatih Birol and is available at https://
www.facebook.com/SecretaryPerry/videos/835183026823612/.
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In just this past Congress, Democrats created a Select
Committee on Climate Crisis, which used nearly an entire
Congress only to deliver a staff report that simply rebranded
Cap and Trade as the Green New Deal. Now, these climate
approaches aimed to uproot the basic underpinnings of our
farming, manufacturing, energy, and transportation systems, and
requires changes for marginal or no benefits which would have
significant implications for the profitability of U.S.
agriculture and the U.S. economy, and specifically, the rural
economy. More so, these recommendations can negatively impact
food abundance and increase food prices all while displacing
U.S. production with that of less efficient, more carbon
intensive, foreign producers, leading to an increase in global
emissions.
Now, these proposals were in direct conflict with the
bipartisan principle that on-farm conservation should be
locally led, voluntary, and incentive-based, principles that
this Committee has put forward and really has been led by.
I truly believe our approach to overcoming this issue must
favor pro-growth solutions over burdensome over-regulations.
Innovation and research must be at the forefront of our
solutions. As a matter of fact, there has been a lot of talk
about legislation or Executive action to address climate
change, but I believe many of these approaches are a solution
in search of a problem. If we really want to reduce global
emissions, hindering U.S. production is the opposite of what we
should be doing. We should be taking steps to ensure the global
competitiveness of our farmers.
Now, though often overlooked, the 2018 Farm Bill is
arguably the greenest farm bill ever, and the farm bill is a
climate bill. Some may scoff at that assertion, but let's talk
about that bill. The farm bill's voluntary programs help
farmers implement new practices that sequester carbon, reduce
emissions, and adopt more energy-efficient farming practices.
These programs have grown significantly in size and scope over
the past 2 decades, providing $6 billion a year to farmers,
ranchers, and forest owners to implement practices like soil
health practices such as cover crops and no-till, that we can
help draw down the carbon and store it in the soil.
The current conservation delivery system is the gold
standard of the world. Our hard-working NRCS field staff, along
with conservation districts, are delivering these benefits not
only to farmers, but to the rural communities. I also believe
that the private-sector can play a role in addressing the
climate crisis. Companies like Land O'Lakes are leading in
conservation finance, converting methane into energy, and
working on private carbon markets.
Now, let me state for the record, I support private
ecosystem markets as long as those markets are focused on
benefits to the producers. I do not think the government should
be intervening in those markets, and I hope we can concentrate
more on proven solutions. I hope all of us can agree that a
much greater expansion and more rapid deployment of high-
quality broadband connectivity is essential in this regard. It
is essential for our rural communities, and it is essential to
data-driven climate solutions. Broadband isn't just needed in
our homes; it is especially needed on our farms as well.
Agriculture is science. It is technology. It is innovation. The
demands of a 21st century farm economy and economically viable
climate solutions depends on reliable connectivity.
Thanks to innovations in agriculture technologies, farmers
are not the only conserving resources, they are doing so while
producing more food, more fiber, and more feed. Productivity
relative to resource use for agriculture is up a whopping 280
percent in the United States since the 1940s, while total farm
inputs are mostly unchanged during this time period.
Now, I believe this is something that isn't talked about
enough. U.S. producers are the shining star when it comes to
resiliency and sustainability. U.S. producers are the answer to
reducing global emissions, not the problem as so many activists
would have you believe. However, without high-speed internet
connectivity at both the farmhouse and the field, many of these
new technologies that have helped create these efficiencies
will never be realized to their fullest potential.
Continuing to build on the conservation success of American
farmers will reap additional emission benefits and increase
U.S. farming's competitive advantage globally. The men and
women who farm our lands are the original stewards of that
land. The left will give them no credit for all of the
advancements they have made in protecting our natural
resources. The wrong approach with burdensome regulations or
policies that dramatically increase costs will harm rural
economics, while displacing U.S. production with that of less
efficient, foreign producers leading to an increase in global
greenhouse gas emissions.
The question we have to ask ourselves is: who do we want
supplying the world agriculture products? Is it the most
efficient, low-emission producer that creates jobs in America,
or the highest emitting sources that create jobs overseas? If
you care about the American farmer, as well as addressing
climate, the answer should be obvious.
Again, Mr. Chairman, thank you so much for holding this
hearing today. I know you believe, as I do, that our farmers
and ranchers can be part of the solution to the climate issues.
Thank you again to our witnesses, and I yield back.
The Chairman. Well, thank you, Ranking Member Thompson.
The chair would request that other Members submit their
opening statements for the record so that we can move on and
begin to hear from our wonderful panel.
[The prepared statements of Mr. Costa and Ms. Pingree
follow:]
Prepared Statement of Hon. Jim Costa, a Representative in Congress from
California
As Chairman of the Livestock and Foreign Agriculture Subcommittee,
I am committed to ensuring that farmers and ranchers have access to
processing and connections to markets for their products. In the 116th
Congress, I worked to establish the new RAMP-UP grant program to assist
existing facilities in making improvements to come under Federal
inspection. I also supported the recent House-passed provisions to
reduce overtime costs for small and very small Federal establishments.
And, I look forward to continuing to work with my colleagues to address
this important issue, but these improvements cannot come at the expense
of food safety. Given some discussion today on expanding sales of
uninspected meat, I would like to submit two letters,* from food safety
groups and from groups representing farmers and ranchers, outlining
concerns with legislative efforts that would undermine current Federal
food safety standards for meat and poultry.
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* Editor's note: the letters referred to are located on p. 329.
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Prepared Statement of Hon. Chellie Pingree, a Representative in
Congress from Maine
I want to thank Chairman Scott and Ranking Member Thompson for
holding a hearing on the important topic of climate change and the
agriculture and forestry sectors. We know that climate change is
impacting agriculture. In Maine, average temperatures have increased
about 3 F since the beginning of the 20th century and the Northeast is
warming faster than other regions of the country. All 16 counties in
Maine were under a U.S. Department of Agriculture (USDA) Secretarial
Disaster designation at some point in 2020 due to severe drought, which
may have been exacerbated by climate change. This is a serious threat
to our agriculture industry, which has an annual economic impact of
$3.8 billion and supports more than 25,000 jobs.
We also know that agriculture affects our climate. There is no
doubt that the primary driver of the climate change we are experiencing
is anthropogenic emissions of greenhouse gases like carbon dioxide,
nitrous oxide, and methane, and there is no doubt that the agricultural
sector plays a measurable role in emitting these greenhouse gases.
While U.S. agriculture has made efficiency gains that have reduced
emissions per unit over the last several decades, agriculture
contributed 9.6 percent of total U.S. greenhouse gas emissions in 2019-
equivalent to 628.6 million metric tons of CO2.
We need to do more to support farmers in adapting to, and
mitigating their effect on, our changing climate. While the climate
crisis poses a serious challenge for farmers, we can increase
resilience, reduce greenhouse gas emissions, and sequester more carbon
in the soil by providing these farmers with additional incentives and
tools to shift to climate-smart practices, while ensuring they have the
technical assistance necessary to successfully adopt them. I appreciate
that there has been broad agreement on both sides of the aisle that
science-based, farmer-driven, and voluntary policies offer the best
path forward. These are the principles I used to develop a bill I plan
to reintroduce in the coming weeks, the Agriculture Resilience Act.
One of the themes of the hearing was the need for education: for
farmers and for the Natural Resource Conservation Service (NRCS)
professionals and extension agents that work with them. USDA's
Northeast Regional Climate Hub is already helping Maine NRCS focus more
on climate-smart practices through regionally specific, ``farm smart''
training. The Agriculture Resilience Act would build on these efforts
by permanently authorizing and better resourcing the Climate Hubs. It
would create a new technical assistance initiative devoting one percent
of farm bill conservation funding to helping producers adopt practices
that increase climate resilience and mitigate their emissions. Both of
these policies were included in the policy recommendations of the Food
and Agriculture Climate Alliance, an industry coalition that includes
the American Farm Bureau Federation represented by Mr. Duvall. The bill
would also support additional research, on-farm energy initiatives,
opportunities to enhance farm viability and improve soil health,
pasture-based livestock systems, and food waste reduction efforts, with
the ultimate goal of making the U.S. agriculture sector achieve net
zero emissions by 2040.
There has also been discussion among my colleagues about the
diversity of American agriculture and how climate solutions cannot be
one-size-fits-all. We know this in Maine--we are a state characterized
by small- and medium-sized diversified farms. The University of Maine
has taken a comprehensive look at the mitigation potential of Maine's
agriculture and forestry sectors and identified potential strategies
that would be most effective for the state, including applying biochar,
reducing tillage, and using more effective manure management. If Maine
farmers collectively adopt these practices, the UMaine researchers
estimate that the sector could mitigate up to 786,000 tons of
CO2 equivalent per year in greenhouse gas emissions, or
about double the sector's current emissions. This would come at the
total cost of $26.3 million per year, or about 0.017 percent of the
USDA's overall annual budget. I have included this report for the
record with my statement.*
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* Editor's note: the report referred to is located on p. 333, and
is available at: https://crsf.umaine.edu/wp-content/uploads/sites/214/
2020/09/UMaine-NCS-Interim-Report_1Sept
20.pdf.
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I look forward to working with my colleagues on the Agriculture
Committee, our partners at USDA, and my fellow producers in Maine to
make meaningful strides to mitigate climate change by helping farmers
to be part of the solution.
[The Chairman.] Once again, I would like to welcome all of
our witnesses, and thank you for being here today for this
historic and very, very critical hearing.
First, we welcome Mr. Jim Cantore. Mr. Cantore is a senior
meteorologist for The Weather Channel who has worked as a
renowned forecaster for more than 30 years, forecasting the
nation's weather day-to-day and reporting live from the field
on severe weather events. He has also helped produce
documentaries on meteorology, broadcasting in historic storms.
Mr. Cantore holds an American Meteorological Society Television
Seal of Approval and received an Emmy award in 2019 for his
work on The Weather Channel's immersive mix reality
storytelling.
Our next witness is Ms. Pamela Knox. Ms. Knox is the
Director of the University of Georgia's Weather Network, as
well as an agricultural climate--excuse me, I am convinced I
can get that last word right--Agricultural Climatologist for
the University of Georgia in the Department of Crop and Soil
Science. She provides outreach and education on climate and its
effect on crops and livestock in the southern United States.
Ms. Knox also serves on the Technical Advisory Boards of the
Southeast Regional Climate Center, or at NOAA and the Southeast
Regions Climate Hub at USDA.
Our third witness today, who I am also so pleased to be
able to invite and join us, is my good friend President Zippy
Duvall. Zippy is President of the American Farm Bureau
Federation. Mr. Duvall has served as President of Farm Bureau
since 2016, and he is a third-generation farmer from Georgia.
He owns a beef cow herd, raises broiler chickens, and grows
hay. Prior to serving as the AFBF President, he was President
of the Georgia Farm Bureau and served on Farm Bureau's Board of
Directors. A gentleman I have had the privilege of working with
for a number of years, even during my years in the Georgia
State Senate.
Next, we will hear from Mr. Gabe Brown. Mr. Brown operates
Brown's Ranch with his wife, Shelly, and son, Paul. Brown's
Ranch is a diversified 5,000 acre farm and ranch near Bismarck,
North Dakota, with a variety of cash crops, multi-species cover
crops, and livestock that utilize grazing and no-till cropping
systems. He is also a partner in the agricultural consulting
company named Understanding Ag.
Our fifth and final witness today, we are pleased to
welcome Mr. Michael Shellenberger. Mr. Shellenberger is the
founder and President of Environmental Progress. He is an
environmental journalist and the author of several books,
including the recently published book, Apocalypse Never. Mr.
Shellenberger was the co-founder and President of the
Breakthrough Institute.
What a panel, and we are anxious to hear from you.
We will now proceed with our hearing and the testimony.
Each will have 5 minutes. The time should be visible to you on
your screen, and will count down to zero, at which point, your
time will have expired.
Mr. Cantore, please begin now.
STATEMENT OF JIM CANTORE, SENIOR METEOROLOGIST, THE WEATHER
CHANNEL, ATLANTA, GA
Mr. Cantore. Chairman Scott, Ranking Member Thompson, and
distinguished Members of the Committee, good afternoon. I am
Jim Cantore and I am a meteorologist for The Weather Channel
television network. I have been a weather forecaster for almost
35 years. I am here today on behalf of The Weather Channel to
testify about the increasing impacts of climate change on the
agricultural and rural communities of the United States, as
well as the impact on the entire U.S. population.
Over the past several decades, scientists from all over the
world have been studying changes in the Earth's atmosphere and
weather patterns. Recent weather observations are confirming
what computer models and scientific theory conclude.
First, climate is warming due to an increase in greenhouse
gases, especially carbon dioxide in the atmosphere. Second, the
changes are overwhelmingly caused by humans. Third, there is a
definite link between increasingly extreme weather and the
warming planet.
Carbon dioxide in our atmosphere has been steadily
increasing, and in response, so have the temperatures. Since
1880, the average global temperature has been increasing at a
rate of .14 F per decade. However, since 1981, the increase is
more than twice that rate.
These numbers may seem small, but much like our body
temperature, the Earth's temperature is remarkably stable.
Simply put, the planet has a fever, and it is getting worse.
The statistics are alarming. The last 7 years have been the
warmest on record. Ice sheets and glaciers worldwide are
melting and draining water into the ocean, raising the sea
level. In New York City, the ocean sits roughly 1 higher than
when the Empire State Building was built in 1930. By the end of
the century, the global average sea level will likely be over
1 higher than it is today, but future pathways with high
greenhouse gas emissions could raise those seas by over 3 by
2100.
Flooding will be a daily occurrence with each high tide
along the Eastern seaboard and Gulf Coast. We already see this
in our country on sunny days in places like Miami, Florida and
Charleston, South Carolina. Extreme temperatures and prolonged
drought are increasing the risk of water shortages and
wildfires over the western U.S. Extreme rainfall events are on
the rise, increasing the chances for more serious flash
flooding, and the strongest hurricanes are getting stronger,
and potentially slowing down.
The costs are staggering. Billion-dollar disasters are on
the rise, and we have a short video to take a look at one from
last year that hit farmers particularly hard.
[Video shown.] \2\
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\2\ Editor's note: the video is retained in Committee file.
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Mr. Cantore. Our Weather Channel viewers are the very
people who climate change is affecting the most. They are our
farmers, our first responders, our airline pilots, our
truckers, our working-class families. While the phrase climate
change has long been politicized in this country, these
Americans are now facing this today in real time what people
thought might be a 22nd century problem. They are seeing their
crops being washed away in 500 year floods, their livestock
killed in monstrous wildfires, and landfalling hurricanes.
In conclusion, I used to question the roots of climate
change theories. I, like many, doubted that climate change had
its origins in human causes. But after covering severe weather
for 3 decades, including more than 100 tropical systems, dozens
of tornado outbreaks, and more floods than I can remember, I am
here to tell you that climate change is real, and we are
absolutely playing a role in this. Not every disaster is driven
by climate change, but more and more, we are seeing things we
have never seen before, and the link to climate change in many
of these events is present.
Our country is suffering. Just ask the folks in Texas.
While these changes are alarming, there is still time. With the
government's help, our farmers will be able to adapt to
changing temperatures and can even mitigate future warming. But
we must act now to make the tough choices that will not only
improve the lives of future generations, but those of all
generations living today and tomorrow. And for those farmers
whose life work is to feed this country and sustain one of the
most time-honored industries of our great nation, we have a
responsibility to help.
[The prepared statement of Mr. Cantore follows:]
Prepared Statement of Jim Cantore, Senior Meteorologist, The Weather
Channel, Atlanta, GA
Chairman Scott, Ranking Member Thompson, and distinguished Members
of the Committee. Good morning. I am Jim Cantore, and I am a
meteorologist for The Weather Channel television network. I have been a
weather forecaster for more nearly 35 years.
As farmers and the entire agriculture industry are aware, weather
is the inescapable and ever-changing environment in which we live. As
our climate changes, weather is becoming more volatile. As we witnessed
last week across Texas and several other states, no person, business,
community or entire state can escape its extremes. Dangerous cold, snow
and ice revealed infrastructure failures, tested the human will for
survival and sadly cost dozens of Americans their lives.
I am here today on behalf of The Weather Channel to testify about
the increasing impacts of climate change on the agricultural and rural
communities of the United States, as well as the impact on the entire
U.S. population. Our job is to prepare Americans for these difficult
times and help them navigate our changing Earth. Our responsibility as
scientists is to follow the data. We are on the side of the American
people, and it is up to us to explain the science in plain terms.
Over the past several decades, scientists from all over the world
have been studying changes in [E]arth's atmosphere and weather
patterns. Recent observations are confirming what computer models and
scientific theory conclude:
Earth's climate is changing faster than at any point in the
history of modern civilization, primarily as a result of human
activities that emit greenhouse gases into the atmosphere.
The impacts are already being felt in the United States and
are projected to intensify in the future--Americans will be
dealing with even more extreme and costly weather in every
season.
The severity of these impacts will depend largely on actions
taken to reduce greenhouse gas emissions and to adapt to the
changes that will occur.
Carbon dioxide in our atmosphere has been steadily increasing and
in response, so have the temperatures. Since 1880 the average global
temperature has been increasing at a rate of 0.14 F per decade.
However, since 1981 the increase is more than twice that rate (0.32
F). These numbers may seem small, but much like our body temperature,
earth's temperature is remarkably stable . . . simply put, the planet
has a fever and it is getting worse. The statistics are alarming:
The last 7 years have been the warmest on record.
Ice sheets and glaciers worldwide are melting and draining
water into the ocean, raising the sea level. In New York City,
the ocean is roughly 1 higher than when the Empire State
Building was built in 1930.
By the end of this century, the global mean sea level will
likely be over a foot higher than today, but if we continue to
emit high levels of greenhouse gases, it could rise over 3 by
2100. Flooding will be a frequent occurrence with each high
tide along the eastern seaboard and Gulf Coast.
Extreme temperatures and prolonged drought are increasing
the risk of water shortages and wildfires over the western U.S.
Extreme rainfall events are on the rise, increasing the
chances for more serious flash flooding.
And the strongest hurricanes are getting stronger.
I have seen these changes firsthand. Over my nearly 35 year career
as a meteorologist at The Weather Channel, I have observed storms
growing stronger, producing more precipitation and bringing destruction
to areas that have never seen similar damage.
On October 8, 2016, I was covering Hurricane Matthew in Lumberton,
North Carolina. My team and I came upon a motel where people had
evacuated from the North Carolina and South Carolina coasts, as their
local officials had instructed them. They came to Lumberton, thinking
that this far inland--about 80 miles--they would be safe from the storm
surge they were facing on the coastline. But what they encountered in
Lumberton was excessive inland rainfall, over 18" in the region. We had
to help evacuate these people in boats to higher ground--due to this
historic flood event. Again, Hurricane Matthew's inland devastation was
evidence that many of these tropical systems are stronger, wetter and
slower moving than we have seen in the past. This storm also left
partially harvested cotton, soybean, and sweet potato farms across
North Carolina submerged. Farmers who lost pigs and chickens barely
recovered before Hurricane Florence hit in 2018. Devastating rainfall
is a trend we are seeing with a likely climate link.
Also, in 2018, Hurricane Michael rapidly intensified to a category
5 upon landfall along the Gulf Coast. The hurricane-force winds lasted
so long, and moved so far inland, the storm devastated the pecan crop
in Georgia. That was the third year in a row the Georgia pecan crop had
taken a hit from hurricanes--and Michael was the coup de grace. Even on
the west side--the weak side--of the storm, across the Florida
panhandle, there were massive timber losses--trees, snapped like
twigs--where you could smell the pine in the air for miles. The crop
losses in Georgia and Florida totaled more than $3 billion. Relief to
farmers was slow, and so is the regeneration of this region's crops
Our Weather Channel viewers are the very people whom climate change
is affecting the most. They are our farmers, our first responders, our
airline pilots, our truckers, our working-class families. While the
phrase ``climate change'' has long been politicized in this country,
these Americans are now facing today, in real time, what people thought
might be a 22nd century problem. They are seeing their crops being
washed away in 500 year floods; their livestock killed in monstrous
wildfires; their children being diagnosed with increasing respiratory
illnesses due to a more hostile atmosphere.
In 2020 there were 22 weather/climate disaster events with losses
exceeding $1 billion each to affect the United States. These events
have been increasing over the last 40 years. The 1980-2020 annual
average is seven events; the annual average for the most recent 5 years
(2016-2020) is 16.
One of the most memorable of these events occurred last August when
we saw one of the costliest severe thunderstorms in U.S. history damage
over 700 miles of the upper Midwest--much of it farmland.
My colleague Dave Malkoff was on the ground in Benton County, Iowa
as farmer Ben Olson was picking up the pieces of his destroyed corn
crop. Early estimates from the Iowa Corn Growers Association put the
loss at around 10 million acres, which is well over a billion bushels
of corn. With a bushel selling for about $3 and 40 each, that's more
than a $3 billion loss. And Mr. Olson and his neighbors are left with
farms of rotting corn.
And whether or not your districts are directly affected by a
disaster, you and your constituents are helping foot the bill. Billion-
dollar natural disasters are on the rise in many parts of the country,
climate change is playing a role. As policymakers, you are well aware
of not only the cost of American lives and livelihoods, but also the
detrimental impact these billion-dollar disasters have on our Federal
and state budgets.
In Conclusion: I used to question the roots of climate change
theories. I, like many, doubted that climate change has its origins in
human causes. But after covering severe weather for 3 decades,
including more than 100 tropical systems, dozens of tornado outbreaks,
and more floods than I can remember, I am here to tell you that climate
change is real and we are absolutely playing a role in this. Not every
disaster is driven by climate change. But more and more we are seeing
things we have never seen before, and a link to climate change in many
of these events. And our country is suffering; just ask the folks in
Texas. While these changes are alarming, there is still time. With the
government's help, our farmers will be able to adapt to changing
temperatures and can even mitigate future warming. But we must act now
to make the tough choices that will not only improve the lives of
future generations but those of all generations living today and
tomorrow. And for those farmers whose life's work it is to feed this
country and sustain one of the most time-honored industries of our
great nation, we have a responsibility to help.
The Chairman. Thank you. Thank you so very much for that
profound and extraordinarily excellent presentation. You
grabbed it where it needed to be grabbed, Mr. Cantore. I hope I
got that right. I will keep working on it as we move.
Next, we will now hear from Professor Knox. Please begin
now.
STATEMENT OF PAMELA N. KNOX, DIRECTOR, UNIVERSITY OF GEORGIA
WEATHER NETWORK; AGRICULTURAL
CLIMATOLOGIST, UGA COOPERATIVE EXTENSION, ATHENS, GA
Ms. Knox. Good afternoon, everyone. My name is Pam Knox,
and it is an honor to speak to you all today. I thank Chairman
Scott and Ranking Member Thompson, and all the Members of the
Committee who are allowing me the chance to share my expertise.
I am an Agricultural Climatologist, and an extension
specialist in the College of Agricultural and Environmental
Sciences at the University of Georgia. I am also the Director
of the UGA Weather Network, which is a mesonet of 87 stations
across the state that provides agricultural information to
farmers and foresters in Georgia. You can see a picture of one
of my stations behind me.
Before I took my current job, I worked as a USDA funded
research scientist studying climate impacts on the Southeast,
and livestock impacts of climate change across the U.S. I am
also a former state climatologist for Georgia and Wisconsin.
What I want to talk about today is the importance of
climate to agriculture and forestry. We know agriculture and
forestry are highly affected by swings in weather and climate.
Year-to-year changes in temperature and precipitation can be
hard for farmers to deal with and making a bad choice of crops
or management practices can be costly. In addition to the
natural variations of the climate, the U.S. is also getting
warmer, as Jim mentioned, due to increases in carbon dioxide,
methane, and other greenhouse gases. Average temperatures in
the U.S. have gone up by almost 2 F in the last 60 years.
Higher temperatures mean longer growing seasons, more heat
stress on livestock and outdoor workers, more time for diseases
and pests to threaten crops, and a more unpredictable water
cycle. It also means more extreme events such as heatwaves,
droughts, and floods that put farmers and foresters at risk by
destroying crops and forests, and flooding fields and pastures.
Agriculture and forestry are being affected by climate, but
they are also contributing to warming temperatures by adding
greenhouse gases to the atmosphere and changing the surface of
the land. Livestock production releases methane into the
atmosphere. Using too much fertilizer adds nitrous oxide into
the air, and also pollutes streams and lakes. Cutting down on
forests and draining wetlands for crops in urban areas releases
carbon dioxide and methane. On top of this, 30 to 40 percent of
all the food produced is never used. This means that the fuel,
water, and fertilizer that is used to produce it is wasted, and
more greenhouse gases are produced as that food waste is dumped
into landfills, and tractors and water pumps are run for no
good reason.
Fortunately, agriculture and forestry can be powerful
helpers in fighting climate change, too. Planting cover crops
can prevent greenhouse gas emissions tied to fertilizers in
irrigation by keeping water, carbon, and nutrients in the
ground in the first place. Growing more trees and improving
cropland productivity can pull carbon dioxide from the air.
Many of these choices also help the farmers' bottom line by
reducing the cost of fuel, agricultural chemicals, and the
labor needed to apply them. A lot of these solutions don't need
to be costly, either. They can be a real benefit to lower
income and Black farmers with limited resources when you use
these simpler solutions.
Climate change is already here, and farmers, ranchers, and
foresters are already learning to adapt to the new conditions.
Some farmers are taking advantage of the longer growing seasons
by double-cropping, or growing new crops like satsumas and
olives in Georgia, for example. Livestock producers are using
shade structures or cooling barns to protect their animals from
heat stress. Foresters are testing out new varieties of pine
and other commercial tree varieties that can survive and thrive
in the future. Many producers are also using smart irrigation
techniques, and other climate-smart management practices to use
water efficiently, while protecting and improving the soils.
But not all farmers know how to use these methods or can
afford to follow them. So, information and training on best
practices need to be available for them to make the best use of
their land. Agencies like USDA, NOAA, NASA, and others have a
long history of providing science-based, region-specific
information and technologies to farmers, ranchers, and
foresters across the country to help them monitor local climate
and prepare for and respond to extreme weather and changes in
climate. Other programs provide financial support for
scientists studying the problems of extreme weather and climate
change.
Knowledge, technology, and funding will all be needed to
make a difference in fighting climate change.
In closing, while farms, ranches, and forests are all
contributing to the increasing greenhouse gases in the
atmosphere, and the rising temperatures that they produce, they
also have the potential to help the U.S. reduce global warming
by reducing emissions as well as absorbing gases from the
environment. USDA and other agencies should be encouraged to
work with farmers and scientists to find the best, most cost-
effective ways to do this.
Thank you all for your attention, and I look forward to the
discussion on this and hearing your comments.
[The prepared statement of Ms. Knox follows:]
Prepared Statement of Pamela N. Knox, Director, University of Georgia
Weather Network; Agricultural Climatologist, UGA Cooperative
Extension, Athens, GA
Key Points
Climate change is impacting agriculture and forestry by
raising temperatures, which: affect the length of the growing
season, degree days and chill hours; cause heat stress
affecting livestock and outdoor workers; enhance
evapotranspiration; and increase the likelihood of extreme
events like floods and droughts, all of which have negative
consequences on farm production.
Agricultural and forest-based practices are affecting
climate change by adding greenhouse gases to the atmosphere and
altering the soil and land used for growing crops and
livestock, adding to the rise in temperatures through release
of methane and other greenhouse gases.
Producers can reduce their emissions of greenhouse gases by
using climate-smart agricultural practices such as using more
cover crops and precision irrigation and by reducing food waste
and overuse of fertilizers and other agricultural chemicals,
which will help slow warming.
Producers are already adapting to changes in climate by
adding cover crops, changing crop and tree varieties, and
adding new crops to their farms as well as adding cooling
structures and irrigation; these actions can make their farms
more resilient to changing climate and extreme weather.
Farmers can benefit economically from conserving water,
fuel, and labor now while they are helping to reduce climate
change by managing their land and animals carefully.
As farming and forestry become more technologically
advanced, new management tools will require access to more and
better local data to help producers make smart choices about
how they manage their farms and forests for health, safety, and
profit.
Introduction
I would like to thank Chairman Scott and the other Members of the
House Agriculture Committee for the opportunity to testify at this
hearing to explore the relationship between agriculture and forestry
and climate change. It is an honor and privilege to be with you today.
My name is Pamela Knox, and I am a Public Service Associate with
Cooperative Extension at the University of Georgia. I am currently the
Director of the University of Georgia Weather Network and an Extension
Specialist in agricultural climatology. I have worked on projects
specifically related to agriculture, forestry, and climate change for
the last decade. Prior to my current position, I was a research
scientist funded by the U.S. Department of Agriculture (USDA) to study
the impacts of climate variability and change on crop production in the
Southeast and on livestock production across the United States. I also
worked with the USDA Southeast Regional Climate Hub to identify how
climate variability and change affect management decisions and day-to-
day activities on working lands across the region. I am currently a co-
Principal Investigator on two projects related to identifying the rapid
onset and expansion of drought using soil moisture monitoring; one is
funded by USDA and the other by NOAA. I am a previous President of the
American Association of State Climatologists and have served as State
Climatologist in Wisconsin and as Assistant State Climatologist in
Georgia. I am also a Certified Consulting Meteorologist and have served
as the Chair of the American Meteorological Society's Board on
Certified Consulting Meteorologists as well as their Board of
Professional Continuing Education and on their Standing Committee on
Applied Climatology. My testimony today is my opinion, based upon my
background and experience in studying agriculture and climate.
Overview
According to the Bible and other ancient texts, agriculture is one
of the earliest signs of civilization. Agriculture and forestry provide
us with the food we eat, fiber we use to make clothing, and building
materials and fuel that we use to provide shelter and keep us warm. In
the United States in 2019, agriculture contributed over $1.1 trillion
to the GDP, a 5.2 percent share of the economy.\1\ In addition,
agriculture provided 10.9 percent of total U.S. employment.
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\1\ https://www.ers.usda.gov/data-products/ag-and-food-statistics-
charting-the-essentials/ag-and-food-sectors-and-the-economy/.
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Of all the sectors of the U.S. and the world economy, agriculture
is arguably the one most affected by swings in weather and climate.
Natural cycles of climate variability in the past have led to changes
in agricultural activity as temperatures have risen and fallen and rain
has come and gone. In periods when the local climate is favorable,
those communities have expanded. Where drought, frosts, and extreme
heat have occurred, agriculture has contracted and sometimes failed,
leading to famine and migration as the citizens moved elsewhere or died
out. Agriculture has also affected the communities around it by
changing the nature of the land cover from forests to bare fields,
affecting the local energy balance, temperature, and water cycle. In
areas where agriculture expanded beyond the capacity of the local
climate to sustain it, the land lost its ability to provide for those
who lived there.
Agriculture has also benefited from the rise of the Industrial
Revolution, which provided agricultural producers with the mechanical
ability to farm larger acreage, reduce the impacts of pests and
diseases, and increase yield through the use of fertilizers and other
agricultural chemicals. This has allowed us to feed a growing
population. These benefits did not come without costs, however, since
use of mechanical equipment requires fuel and factory production.
Agricultural chemicals, when used improperly, have hurt natural
ecosystems and contributed to the growth of toxic algae and diseases in
water downstream. The cost of using this modern equipment has also put
economic strain on lower-income and minority farmers who often have
difficulty getting access to the most recent technology and information
needed to maximize their potential yields. Clearing of land has reduced
forest cover in some areas and released carbon dioxide and other
greenhouse gases into the atmosphere, resulting in changes to the
[E]arth's energy balance.
Since 1895, annual average temperature in the United States has
changed quite a bit from year to year (Figure 1), making planning for
farmers difficult since what happened last year is probably not what
they will experience this year. The annual average temperature has also
changed on longer time scales due the influence of both natural cycles
and human contributions to the global energy balance. Natural cycles
include both shorter-term cycles such as the El Nino Southern
Oscillation (ENSO) related to ocean temperatures in the eastern Pacific
Ocean, and longer-term cycles in the global atmosphere and ocean. Those
natural cycles occur on top of an upward trend that has been linked in
numerous studies to increasing greenhouse gases in the atmosphere,
which act as a blanket that holds the [E]arth's heat near
Figure 1. Contiguous United States Annual Average Temperature from
1895-2020 \2\
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\2\ NOAA National Centers for Environmental information, Climate at
a Glance: National Time Series, published February 2021, retrieved on
February 10, 2021 from https://www.ncdc.noaa.gov/cag/.
the surface instead of allowing it to escape to space. In the 57 year
average lifetime of a farmer in the United States,\3\ the average
temperature has risen by approximately 2 F. Overnight low temperatures
have increased more than daytime high temperatures,\4\ which may be due
to increases in humidity over time or to differences between the
structures of daytime and nighttime atmospheric layers near the
ground.\5\ This is important for agriculture because warmer nights hurt
early-morning workers and prevent steers from gaining weight due to 24-
hour warmth.\6\
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\3\ 2017 Census of Agriculture, USDA National Agricultural
Statistics Service.
\4\ https://science2017.globalchange.gov/chapter/6/.
\5\ https://phys.org/news/2016-03-nights-warmer-faster-days.html.
\6\ https://www.climate.gov/news-features/blogs/beyond-data/
climate-change-rule-thumb-cold-things-warming-faster-warm-things.
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The annual average precipitation of the contiguous United States
has also increased during that farmer's lifetime (Figure 2). As
temperatures rise, the atmosphere can hold more water vapor than
before. The result: as the water cycle has strengthened, both humidity
and temperature have increased. That has not eliminated the year-to-
year swings that occur naturally due to ENSO and other internal cycles
in the global climate system, so farmers still need to be able to
respond to the short-term changes in rainfall, including droughts and
floods, as well as plan for long-term changes that the warmer climate
will bring. Precipitation is also becoming more variable, with more
rain on the wettest days and longer dry spells between rainstorms.\7\
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\7\ https://www.epa.gov/climate-indicators/climate-change-
indicators-heavy-precipitation.
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Figure 2. Contiguous United States Annual Average Precipitation \8\
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\8\ NOAA National Centers for Environmental information, Climate at
a Glance: National Time Series, published February 2021, retrieved on
February 10, 2021 from https://www.ncdc.noaa.gov/cag/.
Changes in temperature and precipitation are also affecting the
frequency and intensity of extreme events, including heat waves,
floods, droughts, and severe weather like hurricanes and derechos, such
as the one that devastated parts of Iowa last August. Floods have
become more frequent and damaging due to a more active water cycle and
increases in vulnerable infrastructure. This infrastructure was built
to design standards for the past climate, which may not reflect what we
are seeing now or will occur in the future. Droughts have become more
frequent and often start and grow more quickly than in the past due to
warmer temperatures and longer dry spells between rain events. We call
these quickly developing droughts ``flash droughts,'' an area I study
in my work. These droughts have a special impact on agriculture because
crops and forage need regular amounts of water to grow and thrive, and
if they do not get it, they can lose health and potential yields very
quickly.
Hurricanes and tropical storms so far do not seem to be increasing
in number overall (although there is a lot of year-to-year variability
based on natural cycles). However, recent research has shown that
hurricanes are moving more slowly over land than they have in the past
and are intensifying more rapidly just before they make landfall, which
increases the damage they can do to coastal areas and crops that lie
along the path of the storms after they come onshore.\9\ Extreme wind
events such as tornadoes and derechos also do not appear to be
increasing in number,\10\ although they may cause more damage than in
previous years due to increases in shade trees and vulnerable
infrastructure.\11\
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\9\ https://www.gfdl.noaa.gov/global-warming-and-hurricanes/.
\10\ https://blogs.ei.columbia.edu/2016/12/01/increasing-tornado-
outbreaks-is-climate-change-responsible/.
\11\ https://www.spc.noaa.gov/misc/AbtDerechos/derechofacts.htm.
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A warmer climate multiplies the risk from these events in the
future by expanding the peak season for extreme events and expanding
the area where they can occur toward the north. Winter storms might be
expected to be less likely due to warmer temperatures, but the increase
in the strength of the water cycle could make them produce more snow or
ice, causing problems for farmers worried about the transportation of
milk from farms to dairies and cutting off electricity needed for
milking or power. Even if the frequency of the storms does not change,
the increased use of sophisticated technology could make them more
vulnerable to extreme weather in the future. Recent events such as the
cold outbreak in the central United States last week have shown us that
we are not even able to respond adequately to weather and climate
extremes similar to ones we know have happened in the past; responding
to the more variable and more extreme weather that we expect to see in
the future as shown by climate models will be even more costly,
disruptive, and challenging.
How Climate Change is Impacting Agriculture and Forestry
Changes that we are seeing in our climate now are affecting
agriculture and forestry in many ways. Rising temperatures are leading
to warmer days and even warmer nights, which reduce heating costs in
winter but increase cooling costs in summer. It also increases heat
stress on both livestock and outdoor workers who are exposed to those
high temperatures. Warmer overnight temperatures also harm some crops
such as corn. The higher temperatures also lead to longer growing
seasons, which Knox and Griffin (2014) estimated at roughly a 1 week
increase in the growing season for every 1 F rise in temperature.\12\
The longer growing seasons provide opportunities for growing new crops
and double-cropping but also lead to longer seasons for pests and
diseases that affect the crops, forests, and animals. Warmer
temperatures are also shifting climate zones to the north, changing the
mix of crops and tree species that can be grown in any area or what
times of year they can be grown successfully. The exact amount of
temperature change that will occur cannot be predicted because there
are so many unknowns to consider, including what choices humans make
about greenhouse gas emissions in the future, but a range of increases
from roughly 4 to 9 F is projected to occur by 2100 by most climate
models, depending on the scenario chosen.\13\ These changes will not be
uniform across the globe; some areas may see greater temperature rises
than others, but all areas will be affected.
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\12\ P. Knox and M. Griffin, Using Analog Methods to Illustrate
Possible Climate Change for Agricultural Producers, https://
ams.confex.com/ams/94Annual/webprogram/Paper232055.html.
\13\ National Climate Assessment, 2018, https://
nca2018.globalchange.gov/chapter/2/.
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More variations in the water cycle provide both positive and
negative impacts on agriculture. Northern parts of the United States
are benefiting from more rainfall and a longer growing season now
versus early in the 20th century. Crops such as corn are expanding into
areas that previously could grow only wheat, for example. But the
increase in the heaviest rain is leading to more erosion and flooding,
both of which hurt farmers who are concerned with soil health and
transportation of products to market. In dry years, longer intervals
between rain events puts extra stress on crops and forests, especially
where the water-holding capacity of soils is low. In the western United
States, warmer temperatures have caused more precipitation to fall as
rain and less as snow, which significantly affects the availability of
irrigation water for crops as well as city water supplies because there
is less storage of water in mountain snowpacks. Droughts are also
expected to become more frequent and longer in a warmer world because
the higher temperatures increase evaporation from soil, streams, and
lakes, and increase evapotranspiration from plants. Even if the total
amount of precipitation does not change, more evapotranspiration will
lead to higher water demands by crops and more evaporation from lakes
and reservoirs will make water shortages more frequent. Increases in
heat spells are also expected to lead to more rapid onset of droughts
and more frequent flash droughts that primarily affect crops and
increase the occurrence of forest fires in the western United States.
The increase in carbon dioxide (CO2) in the atmosphere
is expected to have some fertilization effect on plants, since they
take in CO2 as they grow. However, that effect is limited by
the plant's ability to use the CO2 and the availability of
other required elements, including water and nutrients. Scientists have
also noted that some weeds grow much more quickly in enhanced
CO2 environments than crops do. That could lead to more
competition between crops and weeds, resulting in an increased need for
herbicides, so the benefits from increased carbon dioxide are limited.
In recent years we have had many examples of the devastation that
extreme weather can have on agriculture and forestry. Hurricane
Florence (September 2018) caused tremendous damage to the coastal
Carolinas, primarily due to flooding from rains of up to 36" in
Elizabethtown, North Carolina.\14\ The widespread flooding due to the
slow-moving storm caused tremendous damage to sweet potatoes and other
crops in eastern North Carolina and also caused the deaths of 3.4
million chickens and turkeys and 5,500 hogs. Hurricane Michael (October
2018) intensified just before landfall, bringing devastating winds
through an area stretching from the Florida Panhandle to the northeast
through southern Georgia and on into the Carolinas and Virginia. It was
still a hurricane as it passed through central Georgia on October 10,
and the UGA Weather Station in Donalsonville in far southwestern
Georgia reported a wind gust of 115 mph as the eyewall passed over the
airport location. Losses to agriculture and forestry in Georgia and
Florida were estimated at over $3.3 billion.\15\ The storm hit about a
week before most cotton was expected to be harvested, completely
shredding many fields; it also flattened pine plantations and pecan
groves that had been in farm families for generations, leading to years
of losses of income for those families as they tried to reestablish
their groves by planting new trees. Storms like the 2020 Midwestern
Derecho also show the vulnerability of agriculture and forestry to
severe thunderstorms and extreme weather, although it has not yet been
determined whether these storms will become more frequent in the
future.\16\
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\14\ S.R. Stewart and R. Berg, National Hurricane Center Tropical
Cyclone Report on Hurricane Florence, May 30, 2019, https://
www.nhc.noaa.gov/data/tcr/AL062018_Florence.pdf.
\15\ J.L. Beven, R. Berg, and A. Hagen, National Hurricane Center
Tropical Cyclone Report on Hurricane Michael, May 17, 2019, https://
www.nhc.noaa.gov/data/tcr/AL142018_Michael.pdf.
\16\ https://www.spc.noaa.gov/misc/AbtDerechos/
derechofacts.htm#climatechange.
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How Agriculture and Forestry Are Impacting Climate Change
The growth of agriculture and forestry over time have resulted in
many benefits to our citizens, including better access to food, fiber,
and building materials. But agriculture and forestry have had negative
impacts on our citizens and our climate as well. Food waste due to
inefficient use of farm production and citizen consumption results in
30-40 percent of food being thrown away in the United States,\17\ even
though many lower-income families do not have adequate access to the
food they need. This leads to increased emissions of methane from
landfills where the food is dumped. It also wastes the fertilizer,
fuel, and water that was used to produce that food in the first place
and the time and energy of people that are involved in producing and
transporting that food from farm to market. Using too much fertilizer
also results in the release of nitrous oxide, another greenhouse gas,
which further increases global temperatures.
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\17\ https://www.usda.gov/foodlossandwaste/why.
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Livestock production allows ranchers and farmers to raise high-
quality protein on land that often cannot be used for other economic
activities. However, methane emissions from cattle produce 14 percent
of greenhouse gas (GHG) emissions globally per year, although it is
only four percent of all GHG emissions in the United States.\18\ A lot
of agricultural production goes towards providing the feed these
animals use, and that production also emits greenhouse gases through
the use of diesel fuel, fertilizers, and changes in land use from
wetlands to cultivated crops.
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\18\ https://www.ucdavis.edu/food/news/making-cattle-more-
sustainable/.
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Overuse of fertilizer, especially in areas with frequent heavy
rains, causes problems with toxic water both locally, in rivers
downstream from the fertilized fields, and in the Gulf of Mexico and
ocean estuaries. This affects the livelihood of fishermen there by
reducing the catch of commercial species as well as harming local
ecosystems. It also reduces the health of the stream and estuary
ecosystems and can lead to higher costs to treat the water for human
and animal consumption and industrial uses.
Overall, the inefficient use of water and fertilizer and waste of
food leads to serious economic consequences for agricultural producers,
since they are the ones who pay for the diesel fuel to run equipment
and pumps, and the chemicals needed to fertilize their crops and
protect from weeds, pests, and diseases. Methods to make farms more
efficient are often costly and put an extra burden on lower-income and
minority farmers who cannot afford the cost of the added enhancements,
leading to reduced production and even less money coming in.
How Agriculture and Forestry Can Reduce Emission of Greenhouse Gases
Agriculture and forestry have a large role to play in reducing the
effects of greenhouse gases. The best way to reduce greenhouse gases in
the atmosphere is to prevent their emission in the first place. Then
there is no need to remove them from the atmosphere later. In 2018,
agriculture produced 9.9 percent of the U.S. emissions of greenhouse
gases by economic sector.\19\ Worldwide, agricultural emissions account
for 24 percent of all greenhouse gas emissions. These emissions come
from numerous sources, including livestock production, release from
agricultural soils, and rice production.
---------------------------------------------------------------------------
\19\ https://www.epa.gov/ghgemissions/sources-greenhouse-gas-
emissions.
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There are many ways that agriculture and forestry can help reduce
the output of greenhouse gases. One of the biggest potential new ways
to reduce emission of these gases is through reduction of food waste
and packaging, which reduces methane emission from landfills where the
unused food is buried and also reduces the amount of fuel, fertilizer,
and transportation costs used to produce the food that is not used. It
also reduces the amount of land that needs to be cleared for new crops.
Improved diets for livestock and anaerobic digesters to recover methane
from animal waste can reduce the amount of methane emitted. Using soil-
preserving methods such as growing cover crops helps keep carbon,
nutrients, and water in the soil, reducing the need for fertilizers and
running diesel-powered irrigation pumps. Making production more
efficient by using tools like smart irrigation and better management of
nitrate fertilizers also reduces the emission of greenhouse gases. The
use of solar- and wind-powered pumps, where feasible, can also help cut
the costs of fuel. Using new methods of cultivating rice using less
water-intensive methods may also help to decrease methane emissions.
Changing diets to eat lower on the food chain can also help reduce
emissions.
Farming and forestry can also help by removing carbon dioxide and
other greenhouse gases from the atmosphere. Growing forests and
improving cropland productivity both pull carbon dioxide from the air
as ``carbon sinks.'' Many of the methods that reduce emission of these
gases also help make the land better at removing carbon dioxide. For
example, using no-till methods of farming keeps more water and
nutrients in the soil and increases the health of the soil and of the
plants in those fields, allowing them to suck up more carbon dioxide.
Protection of existing forests and planting of new trees can also help
to remove carbon dioxide from the atmosphere and cool the local
climate. These practices also have other benefits such as protection of
biodiversity, erosion control, and ecotourism, all of which can also
benefit farmers.
Many of these solutions can be implemented now and many farmers are
already doing so. For example, the number of cover crop acres in the
United States increased by 5 million acres from 2012 to 2017, according
to the 2017 Census of Agriculture.\20\ There is also ongoing research
funded by USDA and other agencies into how to make these practices even
better and easier for producers to implement. Because there are so many
different types of agricultural production, there is no ``one size fits
all'' solution. Many of these newer methods of production will result
in economic savings for the producers immediately without large capital
outlays. This is particularly important for lower-income and minority
farmers and will be valuable to producers regardless of how the climate
changes because the newer methods reduce the use of costly fertilizers,
fuel for field work and irrigation, and other expensive inputs.
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\20\ https://www.farmprogress.com/cover-crops/census-finds-cover-
crop-acreage-increases-50-nationwide.
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How Agriculture and Forestry Can and Are Adapting to Changing Climate
Since the climate is already changing and will continue to change
for the foreseeable future based on greenhouse gases that have already
entered the atmosphere or will be emitted in the future, farmers will
also have to adapt to warmer temperatures, longer growing seasons, and
more variable rainfall. In fact, many farmers have already started to
take advantage of these changes. A longer growing season can lead to
the enhanced ability to produce two crops instead of one (``double-
cropping''), or to choose different varieties with higher yield that
take longer to grow. That allows producers to diversify and create
multiple income streams from the different crops they grow. Farmers are
also experimenting with new crops that expand their options for selling
locally at premium prices. For example, in Georgia producers are now
starting to grow satsuma mandarins in the southern parts of the state,
and olive groves and pomegranates have also been introduced to expand
market options. In the northern part of the United States, some areas
that are seeing increased rainfall are now growing corn where it was
not previously possible due to the dry conditions. Expansion of other
crops towards the north may also occur where appropriate soils and
rainfall permit them to grow. However, more research is needed on
whether the changes in climate that are occurring are compatible with
how those crops grow.
Livestock producers are also adapting to a warmer climate by
protecting their animals from heat stress using shade structures, or in
some cases, keeping their dairy herds in air-cooled barns. New breeds
like White Angus have been introduced to see if they can withstand high
levels of heat stress better than current breeds. New hybrids of
commercial crops and fruit such as peaches, which need a certain amount
of cold weather to produce good yields, are being developed to grow in
the new, warmer conditions. Foresters are also testing out different
species of pine and other commercial varieties of trees to make sure
that those forests will thrive under the climate conditions that are
expected to occur as those trees mature. Many of these approaches
require research to learn how to make the best choices, but farmers are
already taking the lead on testing new varieties and new crops to
determine their market values and growth patterns.
What USDA and other agencies are already doing to prepare for changes
in climate and extreme weather
The USDA has a long history of providing science-based, region-
specific information and technologies to agricultural and natural
resource managers across the United States, both alone and with other
Federal and state agencies. This information helps land managers to
make better choices based on scientific principles. The USDA also
provides decision tools and guidance on how to use them so farmers from
a wide range of backgrounds can use them effectively. In 2013, the USDA
Climate Hubs were chartered to ``provide a link between research
activities and practical, actionable information that producers can use
to make climate-smart management decisions''.\21\ They are led by
Agricultural Research Service [1] and Forest Service
[2] senior Directors with contributions from many other
programs including the Natural Resources Conservation
Service,[3] Farm Service Agency,[4] Animal and
Plant Health Inspection Service,[5] and the Risk Management
Agency.[6] The hubs currently address how working lands can
be managed to become more resilient to extreme weather including
hurricanes, wildfires, floods, and droughts. For example, the Southeast
Regional Climate Hub has produced a series of crop-specific hurricane
preparedness and recovery guides \22\ that are being used to help
producers plan for how to deal with hurricanes, which have severely
impacted agriculture in the Southeast over the last 5 years. They also
provide advice for what to do after a hurricane moves through the
region. Other hubs provide information on dealing with drought and
other types of extreme weather and climate that affect many different
types of agricultural production. As an Extension specialist I use the
information from all these sources to help producers make more informed
choices about what crops to grow and how to manage them based on the
current climate and what is predicted in the future.
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\21\ https://www.climatehubs.usda.gov/about-us.
\[1]\ https://www.ars.usda.gov/.
\[2]\ https://www.fs.fed.us/.
\[3]\ https://www.nrcs.usda.gov/wps/portal/nrcs/site/national/home/
\[4]\ https://www.fsa.usda.gov/.
\[5]\ https://www.aphis.usda.gov/aphis/home/.
\[6]\ https://www.rma.usda.gov/
\22\ https://www.climatehubs.usda.gov/hubs/southeast/topic/
hurricane-preparation-and-recovery-southeast-us.
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Other programs within USDA provide financial support for scientists
who are looking for better solutions to problems related to extreme
weather and climate change. I have benefited from several grants from
the National Institute of Food and Agriculture (NIFA), including one to
put together training materials for extension agents and producers on
livestock and climate across the United States and another looking at
the impacts of drought and a warming climate on crop production in the
Southeast. Other initiatives have focused on forestry and tools to help
foresters pick the tree varieties that will do best in the future
climate. USDA is currently providing funds for a project that I am co-
Principal Investigator on that studies the impacts of ``flash''
drought. We are evaluating a variety of low-cost sensors that can be
used by farmers in the Southeast to make water-smart decisions which
will target efficient water use. This will also reduce fuel use and
decrease the amount of fertilizer runoff into streams and, eventually,
the ocean by using water wisely only when and where it is needed.
In addition to USDA, there are many other Federal agencies working
in the area of monitoring climate and preparing for and responding to
weather extremes as well as preparing for future impacts. One of these
groups is NASA; you will hear more about their activities from one of
the other experts in this panel. The agency that I work with most often
is the National Oceanic and Atmospheric Administration (NOAA), which
provides information on real-time weather and climate conditions across
the U.S. and the world. NOAA scientists and employees also work with
many constituent groups on when to expect extreme weather conditions.
They also work with emergency managers to prepare for extreme events as
well as study extreme weather and climate events from the past to learn
better ways to respond to them next time.
In addition to Federal agencies, there are many state and local
agencies and private organizations that are also working in the area of
agriculture, forestry, and climate change. I am proud to be an
Extension specialist at the University of Georgia. Surveys of farmers
show that nearly half (47.8%) of farmers surveyed in a recent study
found university Extension to be the most trustworthy source of climate
change information.\23\ Extension agents serve a critical role in
translating the science of climate variability and change into
actionable decisions that local farmers can use to improve crop yields
today and prepare for variations in climate in the future. We work with
both academic and industry scientists and farmers, including those from
both large and small farms, to identify developing critical conditions
that may affect their crops and to help them plan for future impactful
events.
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\23\ Journal of Extension, https://www.joe.org/joe/2018june/a7.php.
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Cooperative efforts between these groups have already produced
important information about the relationship between agriculture and
climate. The Fourth National Climate Assessment \24\ includes an entire
chapter on Agriculture and Rural Communities that addresses many of the
issues I have mentioned above and relates it to rural communities and
the economies there, which are mainly driven by agriculture. USDA also
released a new publication, Climate Indicators for Agriculture, which
describes how changing climate is affecting agricultural indicators
such as chill hours, growing degree days, extreme rainfall, and heat
stress.\25\
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\24\ 4th National Climate Assessment, 2018, chapter on agriculture,
https://nca2018.globalchange.gov/chapter/10/.
\25\ Climate Indicators for Agriculture, https://www.usda.gov/
sites/default/files/documents/climate_indicators_for_agriculture.pdf.
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Recommendations to enhance efforts to assist agricultural producers
respond to climate change
Based on the climate changes that have already occurred and will
continue to change in the future, there are many ways that Congress can
act to assist producers in both adapting to the ongoing changes and
reducing the emission and concentration of greenhouse gases in the
atmosphere. In general, Congress can encourage the use of research
incentives to scientists to produce more targeted and applied ways of
doing smart agriculture. This should not be done in a vacuum but should
be done through collaboration with farmers using the expertise and
assistance of Cooperative Extension and other groups that work at the
intersection between science and production.
To facilitate the use of smart agriculture, farmers should be
equipped with improved access to resources like the internet so they
can access tools and information that relate climate to agriculture and
forestry. This will help farmers improve their farm and woodlot
management choices and show them how to use the information
effectively. Congress can also encourage access to needed agriculture-
specific data such as the agricultural weather networks (``mesonets'')
that are already in place in some states and encourage their expansion
to other agricultural areas that have fewer resources. This will help
producers make effective decisions which will conserve resources and
save money. This information should also be shared with other countries
because improvements in agricultural production and better capture of
carbon using water, fuel, and agricultural chemicals more efficiently
will benefit the global climate system far more than just doing it in
the United States alone.
In conclusion, I would like to highlight the following four points:
1. The time to act is now.
Reducing greenhouse gas emissions and responding to the
changing climate is not something that can wait until we
have perfect answers. We will never have perfect knowledge
since science is constantly making new discoveries and
farmers are innovating their own production methods at the
same time. If we wait, we will waste time while we put more
greenhouse gases into the air that will require removal.
The climate will get more extreme as a result of those
additional gases. It's better not to emit the greenhouse
gases in the first place. As our mothers reminded us, an
ounce of prevention is worth a pound of cure. The longer we
wait, the more unpredictable and extreme the climate is
likely to become. Technology is always changing, and we can
and must incorporate those changes into our management
plans in the future, but we can take concrete steps now
that will also save farmers money by reducing the costs of
production. You can think of this as a ship captain
responding to the sight of an iceberg ahead. If we respond
to it now, we can make smaller, less drastic changes that
will keep the ship safe, while if we wait, much more
wrenching changes will be needed the closer we get to the
iceberg in the future.
2. Economically, many farmers will benefit from these activities
regardless of how the climate is changing.
Conserving water, fuel, and agricultural chemicals like
fertilizer and herbicides makes good financial sense for
farmers. Improving the health of the soils on farms,
rangelands, and in forests will provide additional benefits
to producers like better fertility and water-holding
capacity, making them more resilient to extreme climate
events like drought. It is especially true for producers
who own the land rather than renting it, because they
receive more tangible economic benefits from improving the
soil, since they may be able to use less water and
fertilizer over time. This is especially important for
producers who want to keep the farms in their families over
many generations, because they need to maintain the soil's
health over many years of production as well as minimize
production costs to keep more money on the farm. Climate-
smart and sustainable agriculture also benefits local water
supplies, municipalities, and ecosystems because resources
are not being wasted or degraded.
Note that not every solution will work for every producer. Farm
size, type of crop or crops, availability of money to use
on farm equipment, and expertise all vary widely across the
U.S. The use of irrigation to reduce vulnerability to
drought may help some commodity farmers but be too
expensive for small farmers unless simpler, lower-cost
alternatives are developed and encouraged. In some parts of
the country, like the Southeast, we usually have enough
water for crops compared to other parts of the United
States, but it sometimes needs to be supplemented to
provide a boost to crops during a hot, dry spell. This
water often only needs to be moved short distances to keep
the crops growing and requires the use of much smaller
infrastructure than the big irrigation projects out West
that move water long distances to get it to the crops that
need it. By working with scientists and producers to find
the best ways to keep their crops alive in a cost-effective
way, the farmers will be able to respond to the climate
variations we are seeing now as well as adapt to and become
more resilient to future climate change. This is especially
important because climate models have a harder time
predicting what the future precipitation patterns will be
than they do temperature patterns, and so flexibility in
how farmers adapt is particularly important. These low-
cost, local solutions will especially benefit Black and
small-scale farmers because they will allow crops to
survive with lower costs than some bigger water projects,
although those also have a place in some parts of the
country.
3. Good management requires good data and useful tools.
The best-managed farms use data to monitor their production and
determine where and when to apply water and agricultural
chemicals and decide when to harvest. Good data can also
tell them when their livestock are under stress and use
appropriate measures to keep them healthy. Tools such as
smart irrigation schedulers and precision agriculture can
cut costs and reduce the waste of fuel, water, and
fertilizer by allowing producers to apply the right amount
at the right time to maximize benefits to the crops without
overusing them. In the future, agriculture will become even
more technologically advanced. Use of machine learning and
artificial intelligence will require good input data, the
availability of computers and internet access, and access
to equipment that can take advantage of this knowledge.
Traditional sources of weather data such as the National
Weather Service collect information that is useful for
farmers, but stations are widely separated and often do not
capture measurements that are agriculturally important such
as soil temperature, soil moisture and solar radiation.
This is where supplemental weather observations from
individual stations and networks of agricultural stations
in mesonets can be of tremendous importance. The House has
already recognized the importance of these mesonets in the
NOAA pilot program enacted under section 511 of the Water
Resources Development Act, which was included in the FY21
Appropriations package. Mesonets like the one that I manage
at the University of Georgia provided tremendous added
value to agricultural producers by increasing the density
of observations, especially in rural areas where
traditional weather observations are rare. They also
provide data that cannot be obtained from more traditional
sources. Production tools based on these data, such as
irrigation schedulers, warning systems for development of
critical pests and diseases, and trackers of crop
development stages can provide highly useful and important
information that farmers can use to minimize expenses and
maximize yield.
To access weather and climate information and use tools
effectively, farmers must have access to both the weather
data and to the tools that use the data to make crop
predictions. That is especially difficult in rural areas
where access to the internet is limited, especially by low-
income and Black farmers. To make maximum use of this
information, rural broadband access must be improved. New
agricultural tools need to be identified by scientists
working together with producers to make sure that they are
useful, reliable, and easy to use. Farmers must also learn
how to use these tools effectively so that they can apply
them to their management practices. Extension and the
climate hubs have an important role to play in making sure
this information is useful and is reaching the farmers who
need it. Use of the data along with the agricultural tools
that use them provide both short-term economic benefits to
farmers by reducing wasted money, fuel, and labor as well
as long-term benefits by reducing emission of greenhouse
gases.
4. Farmers and foresters must be an integral part of the process.
No one knows better how to farm than the farmers themselves.
Innovation in farming has improved productivity
dramatically over time, and farmers will continue to work
to improve efficiency and manage crops better and more
economically. But farmers and foresters must work with
scientists to make sure they are not just doing what they
have always done before, if there is something better based
on science. They also need to know what the future weather
and climate risks to farming and forestry are so that they
manage their land appropriately. Scientists have the
expertise to test new innovations carefully and demonstrate
which ones are the most economical and beneficial. But
scientists need to work with producers to make sure that
the innovations are also practical and cost-effective and
address the issues that farmers have to deal with on a
daily basis.
The USDA Climate Hubs along with other Federal climate centers
have an important role to play in both developing new tools
and information sources for producers and in telling the
farmers and foresters how to use these products
effectively. This can be done through publications, web
resources, and workshops, but they need to incorporate the
input of practicing farmers and foresters as well as
scientists. Extension also has an important role to play in
this process, since extension agents work in the fields
with farmers and see first-hand what problems the farmers
are facing and how available information is used as well as
what is missing. By serving as a liaison between the
scientists and the producers, extension agents bring
together academic and practical experience which will
produce the most effective solutions for agricultural
systems responding to both climate variations like drought
and extreme weather like hurricanes, forest fires, and
floods, both now and in the future. That way scientists and
farmers and foresters can work together to help solve the
problem of climate change in a way that benefits us all.
Thank you again for the opportunity to provide you with this look
at the relationship between agriculture and forestry and climate change
in the United States. I look forward to hearing your comments and
answering your questions on this topic.
The Chairman. Thank you very much, Professor Knox.
And now, Mr. Zippy Duvall, please start now.
STATEMENT OF ZIPPY DUVALL, PRESIDENT, AMERICAN FARM BUREAU
FEDERATION, WASHINGTON, D.C.
Mr. Duvall. Well, good afternoon, Chairman Scott, Ranking
Member Thompson, and all the Members of the Committee. I want
to begin by thanking you for all the help you give our American
farmers and ranchers over the last year and during this
difficult time of the pandemic. It came on top of an already
distressed farm economy, and we are all glad to see some
positive turns.
Keeping our farmers and ranchers in production is vital to
our food security and our national security. As you know,
farmers and ranchers work hard to keep food on our plates,
while continuing to make great strides in sustainability, which
brings us to the topic of today.
American agriculture accounts for approximately ten percent
of the total U.S. greenhouse gas emissions, far less than
transportation, electricity generation, and other industry
sectors. Total carbon sink efforts from forestland, grassland
management, and management of cropland all offset approximately
12 percent of the total U.S. emissions.
To continue to make these gains in carbon sequestration, we
need to increase investment in agricultural research. We need
new technologies to help us capture more carbon in our soil.
Farmers continue to produce more food, fiber, and energy more
efficiently than ever before. Over the last two generations, we
have tripled our production without using more resources from
our land. In fact, we would have to add 100 million more acres
than 1990 to match the same production of 2018.
Our advancements in sustainability are due to adoption of
technologies and our farmers terrific participation in
voluntary, incentive-based conservation programs. United States
farmers have enrolled more than 140 million acres in Federal
conservation programs. That equals the total landmass of
California and New York State together.
Our farms and our land are our heritage. Every farmer I
know wants to leave his land, air, and water and his ranch and
farm business in better shape and better condition than he
found it. To achieve that goal, Congress must protect
agriculture from undue burdens and to respect farmers' and
ranchers' ability to innovate and solve problems. We must work
with Congress to explore new markets and new opportunities for
agriculture.
Farm Bureau's Grassroot Development Process supports
market-based incentives for adopting practices and planting
crops that keep carbon in our soil. We welcome the opportunity
to participate in an emerging carbon market.
To expand these opportunities, we convened a wide group of
stakeholders to explore policy options that respect farmers and
ranchers as partners, while also assuring that our rural
communities can thrive. That effort became known as the Food
and Agriculture Climate Alliance. It consists of organizations
representing a cross section of farmers and ranchers, forest
owners, food sectors, state governments, and environmental
advocates. We are working together to develop and promote
shared climate policy priorities. The Alliance is united under
three principles that guide all 40 recommendations. First, we
support voluntary market- and incentive-based policies. Second,
we want to achieve science-based outcomes. And third, we want
to promote the resilience and help our rural economy better
adapt to climate changes.
We hope the work of, and the recommendations of the
Alliance ensure, farmers and ranchers will be respected and
supported. We must ensure that public policy does not threaten
the viability of our farms, and the long-term resilience of our
rural communities. Americans have a new appreciation for the
importance of agriculture after seeing empty shelves during the
pandemic last year, and I am proud to assure that Americans in
America that the commitment of the farmers and ranchers is
unwavering, and we will still be farming. So, let's make sure
that public policy doesn't stand in the way of our ability to
continue to fulfill that commitment.
Thank you, Mr. Chairman, for holding this hearing today. I
look forward to the questions.
[The prepared statement of Mr. Duvall follows:]
Prepared Statement of Zippy Duvall, President, American Farm Bureau
Federation, Washington, D.C.
Mr. Chairman and Members of the Committee, my name is Zippy Duvall.
I am a third-generation farmer and President of the American Farm
Bureau Federation, and I am pleased to offer this testimony, on behalf
of the American Farm Bureau Federation and Farm Bureau members across
this country.
America's farmers and ranchers play a leading role in promoting
soil health, conserving water, enhancing wildlife, efficiently using
nutrients, and caring for their animals. For decades they have embraced
innovation thanks to investments in agricultural research and adopted
climate-smart practices to improve productivity, enhance
sustainability, and \1\ provide clean and renewable energy. In fact,
the use of ethanol and biodiesel in 2018 reduced greenhouse gas
emissions by an amount equivalent to taking 17 million cars off the
road.
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\1\ https://www.fb.org/land/fsf.
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Livestock and crop production are the heart of American
agriculture, providing the food we enjoy every day. The daily choices
we make on our farm and ranches are driven by our commitment to
sustainability. Farmers have embraced technologies that reduce
emissions and increase efficiency, making U.S. agriculture a leader in
sustainability. Building upon the strong foundation of voluntary
stewardship investments and practices, including those in the farm
bill, we look forward to working with policymakers to further advance
successful sustainable practices in U.S. agriculture. Throughout this
process, lawmakers must ensure that any governmental analysis
characterizing U.S. crop and livestock systems reflects U.S.
agriculture's leadership globally in sustainable farming practices.
All told, agriculture accounts for approximately 10% of total U.S.
greenhouse gas (GHG) emissions, far less than transportation,
electricity generation, and industry sectors. Farmers continue to
produce more with greater efficiency. In fact, U.S. agriculture would
have needed nearly 100 million more acres in 1990 to match 2018
production levels.\2\
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\2\ https://www.fb.org/market-intel/ghg.
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Carbon sequestration, achieved through the management of forestry,
grasslands, wetlands, cropland and settlements contributed to GHG
removals equivalent to 12% of total U.S. emissions. With increased
investment in agricultural research we can develop the new frontier
technologies to capture even more carbon in our croplands, our forests
and our grasslands. We can definitely reduce our carbon footprint. With
cutting-edge science, we may be able to achieve net zero emissions in
some sectors of agriculture.
U.S. farmers and ranchers have long been at the forefront of
climate-smart farming, utilizing scientific solutions, technology, and
innovations to raise crops and care for livestock. These efforts are
designed to protect soil and water, efficiently manage manure, produce
clean and renewable energy, capture carbon, and improve sustainability.
Over two generations, we've been able to increase productivity by 287
percent, while using the same resources. To say we're doing more with
less is an understatement.
Total carbon sink efforts from forestland management, land
converted to forestry, grasslands, and wetland management more than
offset agriculture's contribution to total emissions. However, many of
agriculture's carbon sequestration efforts are not directly assigned to
the agriculture sector. It is certain that if the carbon sequestration
efforts of U.S. farmers and ranchers were assigned to agriculture,
especially our forests, our contributions to GHG emissions would be
lower. It is worth noting that U.S. farmers have enrolled more than 140
million acres in Federal conservation programs--that's equal to the
total land area of California and New York combined. Millions more
acres are dedicated to non-Federal conservation programs.
More productive livestock operations allow ranchers, pork
producers, and dairy farmers to maintain their total contribution to
GHG emissions at less than 3%. Innovation plays an important role, from
methane digesters to advances in nutritional balance that lead to lower
per-unit GHG emissions. In fact, we have seen a 25% reduction in per
unit of GHG emission for our dairy industry, an 18% reduction in swine
and close to a 10% drop for our beef cattle producers.
U.S. farmers and ranchers contribute significantly fewer GHG
emissions than their counterparts around the world. EPA data shows
agriculture's global contribution to GHG emissions was 24% in 2010,
more than double U.S. farmers' and ranchers' contributions to total
U.S. emissions in 2019. This significant difference is largely driven
by U.S. farmers' enthusiastic adoption of technology. American farmers
and ranchers are pioneers of sustainability, and any policy debate
should recognize their contributions, efficiency gains, and the
considerable impact of their carbon sequestration efforts.
With trade challenges and the impacts of the COVID-19 pandemic,
America's farmers and ranchers are facing difficult headwinds. As we
continue to work with Congress, we must explore new markets and
opportunities for agriculture. We also recommend working with our
international trade partners to make certain that national
sustainability standards do not become trade barriers to our
agricultural exports.
At the American Farm Bureau, our policy is crafted by our
grassroots members, hardworking farmers and ranchers, who recognize the
value of a voluntary, market-based system of incentives for planting
crops or adopting farming practices that keep carbon in the soil. That
is why we welcome opportunities for farmers and ranchers to participate
in emerging carbon markets.
To further promote and expand these opportunities, the American
Farm Bureau felt it was important to convene a wide group of
stakeholders to further explore policy options for farmers, ranchers
and rural communities. What came out of that effort is now known as the
Food and Agriculture Climate Alliance which consists of organizations
representing a cross-section of farmers, ranchers, forest owners, the
food sector, state governments and environmental advocates that are
working together to develop and promote shared climate policy
priorities.
The alliance united around three principles that guide our 40
recommendations: Support voluntary, market- and incentive-based
policies; advance science-based outcomes; promote resilience and help
rural economies better adapt to changes in the climate. We hope the
work and recommendations of the alliance ensure farmers and ranchers
will be respected and supported as society pushes for more climate-
smart practices. Advocating for the right policies--voluntary, market-
and incentive-based solutions--will allow us to build on our
sustainability advances and recognize farmers as partners in this
effort, while helping to prevent a move toward the punitive policies
discussed a decade ago.
Farm Bureau will continue to work to ensure that farm families
maintain their ability to respond and adapt to climatic events and that
public policies do not threaten the long-term resiliency of our rural
communities. Congress must protect American agriculture and production
practices from undue burden, and respect farmers' and ranchers' ability
to innovate and solve problems.
American farm families want to leave the land better than when it
was first entrusted to our care. That is the story of my family's farm
in Georgia and the story of millions of farms across this country. We
want to protect the planet, feed and clothe people, and promote vibrant
communities. Working with our partners, land-grant universities,
policymakers, and the farmers and ranchers we represent Farm Bureau
intends to continue finding solutions for the challenges of the future.
Mr. Chairman, I commend you for convening this hearing and for all
your hard work on behalf of agriculture across the country. I will be
pleased to respond to questions.
The Chairman. Well, thank you so much, President Duvall,
for your excellent remarks there.
Now, Committee, before we continue with introducing the
witnesses today, and with the consent of my colleagues, I would
like to share with you now a very brief clip from the
documentary entitled, Kiss the Ground. My dear friend,
Congresslady Jayapal of the State of Washington brought this
film to my attention. I watched it on Netflix. I was very
impressed with what they had to say, and I have invited them to
show this very impressive film. It will introduce you to the
possibilities of how we must balance our climate, replenish our
water supplies, deal with the carbon, and most importantly,
continue being the champions of feeding the world by taking
care of our soil.
Please start the clip now, would you?
[Video shown.] \3\
---------------------------------------------------------------------------
\3\ Editor's note: the video is retained in Committee file.
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The Chairman. Thank you very much for that, and what a very
informative message. I would encourage as many of you to see
the complete film, Kiss the Ground. It is now airing on
Netflix.
And now, we will return to hearing the testimony of the
remaining two witnesses who are here with us today.
Mr. Brown, you may begin your testimony now.
STATEMENT OF GABE BROWN, CO-OWNER/OPERATOR, BROWN'S RANCH,
BISMARCK, ND
Mr. Brown. Thank you, Honorable Chairman Scott and Members
of the Committee, for allowing me the opportunity to speak to
you today.
Since 1991, my family and I have owned and operated a ranch
near Bismarck, North Dakota. As a farmer and rancher, I have
been affected by the extreme variability in weather. Drought,
flooding, extreme cold and heat: the change in our climate is
affecting everyone and every farm. Agriculture is often
vilified as being a major contributor to climate change, but
you can help agriculture become a major part of the solution.
First slide, please.
[Slide.]
Mr. Brown. On the left side of this picture are my soils
today. On the right side are my neighbor's. These samples were
taken only a few feet apart. The only difference is management,
or as I like to call it, stewardship. In 1993, my soil organic
matter levels were at 1.7 percent. Today, they are near seven
percent. My neighbor's are at or below 1.7 percent. Today, my
soils can infiltrate over 30" of water per hour, while my
neighbor's can infiltrate less than \1/2\" per hour.
So, how did farmers like me take large amounts of carbon
out of the atmosphere and use it to regenerate our soils? The
answer is we use six proven time-tested ecological principles.
These principles will work on every farm in every one of your
districts.
Next slide, please.
[Slide.]
Mr. Brown. We start with context. We are not planting
orchards in the desert. That is out of context. We are making
our farms more resilient, but programs like crop insurance are
not rewarding farmers for positive outcomes, and they are not
based on environmental constraints. We are serious about not
only reducing and eliminating tillage, but also significantly
reducing all synthetic fertilizers and pesticides as they harm
soil biology, our ecosystems, and our health.
I am holding a pint jar of treated soybean seed. The
neonicotinoids on this seed has the capability of killing 72
million bees. This has to stop.
Next slide.
[Slide.]
Mr. Brown. Allan Savory said it well when he said ``It's
not drought that causes bare ground, it is bare ground that
causes drought.'' We are keeping our soils covered with diverse
living cover crops and grain crops, thus continuing to pump
carbon into the soil, while protecting our soils from erosion,
conserving moisture, and holding nitrates, phosphates, and
other nutrients on our farms. We are prioritizing diversity.
This Committee can help every farm, ranch, and CRP land to
significantly increase the biodiversity of plants, insects, and
soil biology.
We realize the importance of grazing animals. Our richest,
healthiest soils were formed in partnership with grazing
ruminants. Proper use of grazing ruminants is one of the keys
to carbon sequestration.
Next slide, please.
[Slide.]
Mr. Brown. Down to 36" and beyond, adaptive regenerative
grazing is seeing total carbon gains significantly higher than
rotational or continuous grazing.
Next slide.
[Slide.]
Mr. Brown. This is the Chihuahuan Desert. Many think that
with only 6" to 8" of annual rainfall, it was always a desert.
Next slide.
[Slide.]
Mr. Brown. The dark colored soil near the surface is
carbon. This means it was recently a vast grassland. The
erosion you see took only 60 years. You can drive through this
desert, and then you open a gate to Alejandro Correo's ranch.
Next slide.
[Slide.]
Mr. Brown. The difference is stewardship. He is using
livestock to regenerate his soils and increase biomass. Where
his neighbors need 300 acres to feed one cow per year, he only
needs 30. As a result, regenerative farmers are substantially
increasing the profitability of our farms and ranches, thus
helping to revitalize our rural communities while producing
food that is higher in nutrient density. We have done this
while reducing our reliance on government programs. These
programs should be a hand up or a reward for positive results.
While more resources are needed, just increasing funding
isn't going to solve it. We need to put that funding into what
actually regenerates landscapes. We must make the adoption of
regenerative ag available for all farmers from all backgrounds.
From farmers to scientists to environmentalists to the
government, we hear: ``I didn't know.'' Well, at one time, I
didn't know either. We must educate, not only farmers and
ranchers, but all society as to these concepts which are rooted
in indigenous knowledge.
It is not just about emission reductions. It is about our
land's resilience and ability to function. Regenerating our
soil ecosystem is the most cost-effective national investment
we can make to mitigate climate change and heal society. The
current system is broken. We need to change the way we see
things. Regenerative agriculture is a win for all, and this
Committee, Mr. Chairman, can help lead the way.
Thank you for your time, and I look forward to your
questions.
[The prepared statement of Mr. Brown follows:]
Prepared Statement of Gabe Brown, Co-Owner/Operator, Brown's Ranch,
Bismarck, ND
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Thank you, Honorable Chairman Scott, and Members of the Committee,
for allowing me the opportunity to testify before you today.
My name is Gabe Brown. I own and operate a 5,000 acre ranch near
Bismarck, North Dakota with my wife, son and our family. We have farmed
this land since 1991 and began by using conventional methods, but crop
failures due to erratic weather, increased costs and rising debt led us
to adopt a series of regenerative soil health practices. These
practices have provided multiple benefits. Regenerative practices have
made our farm profitable over the past 3 decades, and also increased
our soil carbon over six-fold since we first started taking on-farm
measurements in 1993.
Today I make the case for wide-scale adoption of regenerative
agriculture by sharing the essential opportunities afforded to me.
Regenerative agriculture mitigates climate change while increasing
resilience against current and future climatic uncertainty including
flooding, fire and drought. It is essential to soil, plant, animal,
human, community, and economic health. Regenerative agriculture does
this by restoring our land and soil, the biology and the ecological
cycles and processes which are foundational to human and planetary
health and stability.
As a farmer and rancher, I have been affected by the extreme
variability in weather. 2020 was the second driest year ever recorded
where I live and ranch in Burleigh County, North Dakota. Just this
month the local weather station recorded the most consecutive days of
^25. From drought to flooding, from extreme cold to extreme heat, the
change in our climate is affecting everyone and everything, especially
farmers.
In 1997, I had the good fortune of hearing Don Campbell, a rancher
from Alberta, Canada present at a conference and Don made this
statement, ``If you want to make small changes, change the way you do
things; if you want to make major changes, change the way you see
things.''
This statement changed my life. I realized that the resiliency of
my farm was up to me. The ability of my farm to cope with climate
change was up to me.
As a farmer educator, I travel all over this country and have
visited hundreds of properties. With my colleagues, I am currently
involved with farmers and ranchers managing over 22 million acres in
the U.S. The realities that these land managers are facing on the
ground are alarming. One thing, however, remains constant, when a
farmer or rancher changes how they see things, real regeneration starts
happening
I want to be clear: farmers and ranchers are the heart of this
country and so many of them are incredible stewards of our land.
However, land use, particularly the shift to our modern systems of
agriculture in the United States and across the world has been one of
the biggest drivers of many issues we face today such as drought,
flooding, soil loss and erosion, and the depletion of water resources,
often attributed broadly to ``climate change''. Through mismanagement,
our land and our soil is now heavily degraded and in many cases barely
functioning, or worse, completely desertified.
Today, climate change is exacerbating the equally serious problem
of degraded land. Scientists estimate that ``75% of land is degraded''.
IPBES
It's not just a question of carbon or greenhouse gases. We've
broken the hydrological cycle, carbon storage capacity, and nutrient
cycle. Much of our land's soil is degraded to such a state and not
functioning as it once did.
We have to come to grips with the reality that the current state or
our soils is dire. We are losing 1.7 billion tons of soils annually
(Cornell University). That is 4 tons of topsoil per acre per year on ag
land (USDA).
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Continuing on this trajectory should no longer be an option.
The Economic Toll of Modern Agriculture in the U.S.
The average debt increase for farmers is 4.1% a year since
1990 (USDA).
Percentage of net farm income from government support is
increasing at an alarming rate; it's projected at almost 40% in
2020 (USDA).
The cost of inputs, including fertilizers, herbicides,
pesticides, etc. is rising for farmers due to the degradation
of our soils.
Crop insurance payouts continue to rise, adding a burden to
taxpayers.
The cost of crop insurance has been an average $7
billion a year since 2013 (USDA-RMA).
However, U.S. agriculture can and must be a major part of the
solution. We can rebuild our soils through regenerative agriculture.
Rebuilding our soils means rebuilding resilience, strength, and freedom
for our nation.
Whether your primary concern is a farmer's bottom line, rural
economic recovery, climate mitigation, sequestering carbon, reversing
biodiversity collapse, cleaning our water and air, rehydrating our land
so aquifers charge and springs flow again, providing land access for
minorities and beginning farmers, or addressing the health crisis,
regenerative agriculture provides the solution.
In 1991, my wife, Shelly, and I purchased a degraded ranch near
Bismarck, ND. Soil tests showed that Soil Organic Matter levels (Soil
Organic Matter is about 58% Carbon) were from 1.7% to 1.9%. Soil
scientists tell me that historically, soil organic matter levels were
between 7% to 8% in my region. This meant that approximately 75% of the
soil carbon had been washed away or released into the atmosphere due to
previous farming practices. This rate of soil carbon loss is all too
common throughout the United States. Soils in North America have lost,
on average, 20% to 75% of their carbon stock.
I also performed water infiltration tests. They showed that my
soils could only infiltrate \1/2\" of water per hour. This meant that
any rain event in which I received more than that amount the water
either ponded on the soil surface or ran off, in the case of any sloped
land, carrying with it precious topsoil and nutrients. Top soil loss
and artificial nutrient run off becomes problematic downstream with
fish kills, water quality issues, and more.
On Farm Soil Comparison: Regenerative vs. Conventional
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In the picture you see before you, on the left-hand side of the
screen are my soil's today (well aggregated and higher carbon levels).
On the right-hand side of the screen are my neighbor's soils (compacted
and mostly devoid of carbon). These samples were taken only feet apart.
They are the same soil type. The only difference is management, or as I
prefer to call it, stewardship.
Today, organic matter levels on my farm are from 5.7% to 7.9%. My
neighbors are 1.7%
Today, my soils can infiltrate 30" of water per hour, while my
neighbor is still lagging around \1/2\" per hour.
That is a 60-fold increase. In places around this
country riddled with flooding, this could create massive
reductions in damage and allow for us to retain precious
water versus having it runoff carrying pollutants and
sediment.
As I am often quoted saying, ``it is not about how
much rain falls, it's how well you absorb and retain it''
Today, I do not use any synthetic fertilizer, pesticides, or
fungicides. As a result of lower expenses and increased production my
profits have increased tenfold.
So how does soil regeneration work?
The soil system evolved to be self regenerating and self healing,
otherwise there would never have been soil to begin with. So,
rebuilding soil is all about helping nature to do it using a system
running on carbon energized by the sun--basically, maximizing
photosynthesis--the ability for plants to use the energy from the sun
to take carbon from the atmosphere and pump into the soil as liquid
energy (glucose and water).
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Building Functioning Soil
Nature also evolved to create functioning soil. Plants share their
sugars with the microbes in the soil who not only make minerals and
nutrients available to plants but also create glues that bind the soil
particles together forming aggregates. This is what causes the primary
difference between soil and dirt where soils contain organic matter
(i.e., carbon-based compounds) and dirt is only mineral--sand, silt and
clay.
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Healthy soil performs like a sponge.
Healthy soils are able to hold 20x their weight in water due to the
pore space between aggregates which also allows for faster infiltration
rates. The substances building the aggregates, the glues from the
microorganisms, and the organic matter within the aggregates are carbon
based and often very stable (meaning it can remain as soil carbon for
years). Thus, the CO2 in our atmosphere can and must become
the glue that rebuilds our soils so they can function again.
How Regenerative Soil Health Practices Build Soil Carbon Over Time
Gabe Brown's Soil Carbon Data
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Carbon Bank/Markets: if we move this direction please take in mind
these four areas of concern.
1. Integrate other outcome areas while building out carbon models so
they aren't separate (i.e., hydration, biomass,
evapotranspiration, biodiversity, etc.)
2. Large scale ground truthed calibration with real-time satellite
data so it is based on outcomes.
3. Make sure at least 50% of all monies from carbon (or other
services) make it to the farmer.
4. Make sure all corresponding data like precipitation, humidity
index, etc. are included in the baseline so equal setting
is created for every state and region.
Regenerating healthy soil is the solution.
The Benefits:
Massive carbon sequestration potential.
1. Adaptive ``Regenerative'' grazing cases have shown the top
12" of soil
are adding 4.76 tons (short U.S.) C/acre/year and
17.46 (short U.S.)
tons CO2/acre/year.
Increase water holding capacity and absorption.
1. 1% increase of Soil Organic Matter means 18-25 thousand
more gallons
per acre held.
Biodiversity
1. Life in the soil means more life on the land (birds, bees,
game, etc. re-
turn)
2. 1 teaspoon of healthy soil holds more organisms than people
on [E]arth.
Resilience/risk mitigation
1. My colleagues and I work with hundreds of farmers totaling
22 million
acres of land. The average we are seeing is only \1/
2\" of water infiltrated
per hour.
2. My farm started at this same rate and now can absorb 30"
rainfall per
hour.
Healthy plants and Farmer Profits
1. Healthy soils make healthy plants that are pest and
disease-resistant
and require less input costs because the life in the
soil makes the nutri-
ents available to the plant.
a. In partnership with General Mills, Understanding Ag
tested 45
farms that averaged 9,000 pounds of nitrogen in
the top foot of the
soil profile.
b. In most cases, soils are not deficient in nutrients,
they are
deficient in biology.
c. Biologically active soils can help farmers reduce input
costs. 7k acre
farms, like Rick Clark's in Indiana, are saving
$860k a year on
input costs.
Why are farmers moving toward regenerative?--They want out of this
endless cycle of debt and dependence. They want freedom. They want to
see their sons and daughters interested in carrying on the legacy of
their family farm. At the very least they want to provide for their
families and keep them safe. The shift is huge, once they start working
with nature instead of against her, their lives completely change. We
work with every type of farmer, large, small, organic, conventional,
wealthy, and in debt. We work with every race, religion, and creed. We
work with White, Black, Latino, Asian, and Native American farmers.
Regenerative agriculture came about because farmers were hurting, this
is an incredibly interconnected movement from the soil up.
The demand to successfully transition to regenerative
agriculture is here and it is growing. And it means each of you
can work to make sure that option is available to all farmers.
At the very least encourage, and if needed, facilitate early
adoption.
To move to regenerative on a massive scale with any type of farming
and ranching we have to prioritize these six principles.
Context
Nature always acts in context. It does not try to grow
plants or raise ani-
mals out of context of where they should not be growing
or living.
Programs like crop insurance are currently not based on
positive outcomes
and don't work in context, often leading to continued
nationwide degrada-
tion of our soils.
We need to monitor for real outcomes as to benefit
farmers building resil-
ience into their operations.
Crop insurance needs to integrate environmental
contexts so we aren't
creating unnecessary harm.
Our financing and loan system for farmers is often out
of context keeping
farmers on an arbitrary hamster wheel of trying to pay
back principal bal-
ances. It could be changed to an investment model that
helps farm and
ranch operations move to regenerative.
Orchards in the desert. Example of bad context.
Least Disturbance
We have to get serious about reducing and eliminating
tillage.
We have to reduce chemicals. Nature does not use copious
amounts of
chemicals.
The chemicals, herbicides, fungicides,
insecticides, even the fertilizer we
are putting on our crops are damaging our soils.
Living Root
Living roots in the soil as long as possible throughout
the year. Nature al-
ways wants a living plant to take carbon out of the
atmosphere, through
photosynthesis convert it to carbon compounds that it can
pump into the
soil to feed microbes. That is what makes rebuilding soil
possible.
We need a massive mobilization of multispecies cover
crops and mentorship
from experienced individuals to ensure their success. We
need 75% of our
cropland covered in the offseasons as soon as possible.
We need viable options like roller crimpers for
termination of diverse cover
crops.
CRP can be beneficial but it is highly underutilized for
actual regeneration.
It needs diverse mixes of species not monocultures of
shallow-rooted grasses
that have poor nutrient quality. It needs to include
regenerative grazing.
Soil Armor
Walk through the forest, there is a carpet of leaves.
Walk through a healthy
prairie and every inch is covered in plants, deep-rooted
grasses, and forbs.
Nature always wants to cover the soil to protect it from
wind erosion, water
erosion, and evaporation to keep building soil
aggregates.
We have to think holistically. We have prioritize every
square foot of soil
and how well the soil is performing versus leaving
thousands of acres bare
and exposed while investing in small infrastructure
projects and thinking
we've accomplished our goal. (without armor, every bare
inch of soil be-
comes vulnerable to water droplets that act like bombs to
soils aggregates
exploding them and leaving dispersed state soil easily
compacted and able
to wash away).
Increase biodiversity
Where in nature do you have a monoculture? The answer is
only where
human intervention has dictated it. Nature thrives on
diversity, yet what
do we do? We plant monocultures, corn, soybeans, wheat,
cotton, rice, and
the list goes on.
As policymakers, you can help change this! Every working
farm, ranch, or
land in CRP can significantly increase the biodiversity
of plants, animals,
insects, and soil biology.
This pint jar of soybean seed that I am holding has been
treated with
neonicotinoids and has the capability of killing
72,350,000 honeybees from
the amount of chemical alone.
Animal Integration
Ecosystems do not function properly without animals.
Many of our richest,
healthiest soils evolved with, and were formed in
partnership with, grazing
ruminants. Proper use of grazing ruminants are one of the
keys to taking
massive amounts of carbon out of the atmosphere,
especially in more brittle
environments that were originally grassland systems
maintained by large
herds and the indigenous people of this land.
We must work together to bring back animals into our
farming systems. We
have to understand the profound opportunities and the
differences of
Adaptive ``regenerative'' grazed land versus
``rotational'' grazing or ``contin-
uous'' grazing.
Compare soil carbon data--total soil carbon tons
per acre.
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
TSC.
And, we can do this faster than we ever thought possible! As my
associate Dr. Allen Williams says, ``outcomes that used to take us 15-
20 years we are now seeing occurring in 3-4 years.''. What he is saying
is that the advances in how quickly farmers can regenerate landscapes,
all while reducing input costs, continues to improve.
This is the Chihuahuan desert in Texas. Many think that with only
6-8" of annual rainfall it was always a desert[.]
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
But take a close look at this picture. See the dark-colored soil
near the surface? That is carbon. This was recently a vast grassland.
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
This is erosion and is happening more and more across
the whole country. Look closely to see the barbed wire
going across this gully. This erosion occurred in just the
past 60 years.
I want to ask you all to take this back to your own
states and districts. Think about places you grew up in or
how your grandparents described the landscape, I want you
to become present to the rates of land degradation that are
happening all around us now. Climate change is exacerbating
it but the management of the land is of the utmost
importance.
Look for dried up streams or riverbeds. Look for bare
land that once was
vast prairie
It's all connected. We are drying ourselves up and
leaving our land vulner-
able.
You drive through this desert and then you open a gate to enter
Alejandro Corrillo's ranch.
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The difference is simply stewardship. Alejandro has used livestock
as a tool to regenerate his soils and increase biomass. Where 12 years
ago he needed 300 acres to feed one cow per year, he now only needs 30
acres per cow. Note: Regenerative grazing in less brittle environments
like Alabama see ranches going from 11 acres needed per cow/year to 2
in under 3 years.
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
By practicing Regenerative Agriculture we can use nature's proven,
time-tested principles to take massive amounts of carbon out of the
atmosphere and build it back into the soil.
4 Short Case Studies
I want to very quickly share four case studies to show that this is
not an anomaly for my ranch in North Dakota or Alejandro's in Texas.
Yes, this can happen with farmers in your district.
Rick Clark (5th generation Farmer Indiana--Regenerative Organic)
7k acres growing alfalfa, yellow field peas, cattle, soy,
corn, and wheat
By moving to no-till and cover crop and planting into
crimped cover crop ``planting green'', he eventually removed
all chemical inputs (no synthetic fertilizer, pesticides or
fungicides ``farming nacked'')
Savings on inputs approximately $860k annually (based
regional averages).
His water infiltration rate has improved to 5" rainfall per
hour.
4 bushel a year increase (for past 4 years) for corn. 1.5
increase for soy.
Adam Grady (11th Generation North Carolina)
1,600 acres cattle, pasture pigs, sheep, corn beans, pasture
turkey, corn, and soy.
Moved from tillage to no-till and cover w/livestock
integration
``In our second year, we saved over $200k by reducing
input costs such as seed, pesticides, herbicides,
fungicides, and fertilizer as well as reducing labor, and
fuel costs.
We had also reduced Glyphosate consumption by 80% and were
glyphosate free by year 3.''
Adam Grady Dark Branch Farms.
Was able to seed 2 week[s] after hurricane Florence waters
receded while neighbors were still flooded.
Was able to pay off his farm debt after only 3 years of
farming regeneratively.
Adam Chappel (Arkansas)
the 8k acre cotton farm was spending $100 an acre on
herbicides, ``there was no way for us to be profitable''.
Switched to no-till and cover cropping now they are making
100-250 an acre profit.
``I don't care what you call it, I call it profitable
farming''--Adam Chappel
Dr. John Boyd (4th Generation Farmer Virginia)
1,300 acres growing corn, soy, wheat, beef cattle, goats,
pigs, vegetables, and hemp.
Transitioning to regenerative practices has lead to
Much native biodiversity being restored.
Major water and input savings.
Working with Tribal communities reintroducing hedgerows of
elderberries into lands and pastures.
As founder of the National Black Farmers Association, John
works to help black farmers access NRCS soil health programs
and get education in regenerative management.
This hearing is about climate change. But those of us who farm and
ranch, it is so much more.
By practicing Regenerative Agriculture we can use nature's proven,
time-tested principles to not just take massive amounts of carbon out
of the atmosphere but we can use it to build back our soils, for farms,
families and futures.
We can restore the water cycle and replenish underground
clean water sources making droughts less frequent.
We can infiltrate water more quickly and hold more water
thus alleviating flooding.
We can hold nutrients on the landscape, thus preventing
nitrates and phosphates from entering our watersheds.
We can make farming and ranching profitable again by
reducing inputs and stacking enterprises.
We can revitalize our rural communities by diversifying farm
production.
We can produce food that is higher in nutrient density thus
significantly lowering healthcare costs[.]
We can Regenerate America[.]
Mr. Chairman, you and your Committee Members have the opportunity
to foster this change. You can develop, adjust, or expand policy that
will allow agriculture to be part of the solution. More resources are
needed, but just increasing funding isn't adequate. It all starts with
education and a ``change in how we see things.'' We must educate
farmers and ranchers as to these regenerative principles. But it's not
just the farmers, this is systemic, the crop advisors, the field
agents, and all society, need more education on the ecological approach
and how and why regeneration of the land can and must happen.
From farmers, to soil scientists, to leading environmentalists, to
government officials, you hear a resounding phrase, ``I didn't know''.
Well, I didn't know either. This is an opportunity for all of us to
learn.
While many of these concepts are rooted in indigenous knowledge,
many of them are being relearned and shaped by our current context and
are emerging with science. We are living in a time like no other, we
need science, technology, indigenous wisdom, and holistic thinking
working together to move us toward regeneration.
Building back healthy soil is the most cost-effective regional,
state, and national investment. From risk mitigation to farmer
prosperity, to human health, to carbon sequestration, it's a win, win,
win, win, and this Committee, Mr Chairman, can help lead the way.
Thank you for your time and I look forward to your questions.
Attachment
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]
The Chairman. Thank you for your excellent testimony.
And now, we will hear from Mr. Shellenberger. Please begin
now.
STATEMENT OF MICHAEL D. SHELLENBERGER, FOUNDER AND PRESIDENT,
ENVIRONMENTAL PROGRESS, BERKELEY, CA
Mr. Shellenberger. Thank you very much. Thank you very much
for inviting me. It is a pleasure to be here.
I will just jump right in by sharing special slides that I
have prepared for the Committee.
So, let's see. As background, because I am going to present
some information that may surprise some people, just my
credentials. Time Magazine ``Hero of the Environment'' and
Green Book Award winner. I have been working with James Hanson,
the climate scientist, and others to protect nuclear power
plants, but I also have a new book out on the environment
called, Apocalypse Never. While I am an environmental advocate
and a climate advocate, I am also concerned by a growing
alarmism, which I think is not conducive to sober and sound
climate or environmental policy.
I want to draw attention to some important positive trends
that many people don't know about. American farmers are world
leaders in innovation, productivity, environmental protection.
You can see here, our crop yields continue to rise dramatically
over the last 30 years, whether it is soy, wheat, corn. You can
see that globally we produce enough food for two billion people
right now. I think a lot of us experienced the fact that we
have too much food available. It is a new problem in human
history to have so much food. We produce 25 percent more food
than we need every year. The result is that extreme poverty has
declined dramatically. Globally, just ten percent of all humans
live in extreme poverty today, down from about 50 percent just
a few decades ago. Life expectancy has increased 40 years, and
you can see that soil erosion has declined in the United States
40 percent, while yields have risen. A very impressive
achievement. We have increased meat production. We have doubled
meat production, even while reducing greenhouse gas emissions.
Incredible success that we don't hear enough about this. A big
part of the reason is that we have cut the feeding time for
various animals, including chickens, while doubling their
weight.
You can see the big problem with degraded soils are in
developing and poor countries, which I will come back to, but
they are experiencing soil loss at twice the rate of wealthy
and developed economies like the United States.
The evidence is clear: technological change and
agricultural modernization will significantly outweigh climate
change in the United States and around the world. This is a
very important report that was produced by the United Nations
Food and Agriculture Organization in 2018 called, The Future of
Food and Agriculture.\4\ Just to help you understand what you
are looking at here, you can see that what it is showing is
that whether you are an irrigated system or rain fed system,
and whether you are in the business-as-usual scenario, the
sustainability scenario, or a scenario of greater inequality,
what really matters is technological change. Just think of it
as fertilizers, mechanization, and irrigation are the big
three, but certainly better seed types massively outweigh the
changes to temperature. This is important because climate
change is real. It is a serious problem. We should do something
about it, but we are not helpless, and if farmers continue to
do what they know how to do, which is to adapt, we are going to
do very well.
---------------------------------------------------------------------------
\4\ Editor's note: the report referred to is retained in Committee
file and is available at: http://www.fao.org/3/I8429EN/i8429en.pdf.
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And in fact, the U.S. Government's fourth National Climate
Assessment says very clearly that we can adapt to climate
change through innovation and adaptation. They point to
different seed types, crop rotations, cover crops, irrigation,
managing heat stress, pest and disease management as the keys.
If every nation raised its agricultural productivity to the
level of its most successful farmers, global food yields would
rise as much as 70 percent, and they could rise another 50
percent if nations increase the number of crops per year to
their full potential.
I think that one of the most important things that the
United States can do is to work with the World Bank and other
institutions to help poor and developing nations to modernize
agriculture for economic development, environmental and public
health reasons. We saw with the coronavirus pandemic, assuming
that the conventional explanation of the coronavirus pandemic
is accurate, it was a spillover of a zoonotic virus, perhaps
from a bat, and perhaps through a pangolin from low yield
farming in south China. We need to modernize meat production,
pull meat production away from forest frontiers. We need to
help countries to do that. It is in all of our interests to
modernize meat production agriculture, and there are good
environmental reasons. You can see that because we have become
so much more efficient globally, we have actually reduced the
amount of land that we use for meat production, which is the
single-largest use of the Earth's surface by humankind, by an
area almost the size of Alaska. We know that the most efficient
meat production in North America requires 20 times less land
than the most efficient meat production in Africa. You can see
there a scaled-up picture of that efficiency. We know that
industrial meat production is far more efficient than pasture
meat production, and produces a fraction of the carbon
emissions, just by concentrating that meat production. In
Brazil, we could save an area twice the size of Portugal----
The Chairman. Thank you.
Mr. Shellenberger.--and restore a rainforest without
impeding agricultural expansion.
I will just close by saying carbon emissions in the United
States have been going down for many years. We are on track to
meet our climate agreements. Deaths for natural disasters have
gone down. There was some talk of increased costs of extreme
weather events. In fact, as a share of GDP, they have gone down
significantly.
I would just say----
The Chairman. Thank you.
Mr. Shellenberger.--to somebody that is concerned about
climate change and other issues, we should just consider the
fact that we are in the midst of a very serious drug overdose
epidemic, which killed about 81,000 people last year in
contrast to extreme weather, which only killed 413.
Thanks very much.
[The prepared statement of Mr. Shellenberger follows:]
Prepared Statement of Michael D. Shellenberger, Founder and President,
Environmental Progress, Berkeley, CA
Good morning Chairman Scott, Ranking Member Thompson, and Members
of the Committee. My name is Michael Shellenberger, and I am Founder
and President of Environmental Progress, an independent and nonprofit
research organization.\1\ I am an invited expert reviewer of the next
assessment report by the Intergovernmental Panel on Climate Change
(IPCC), a Time Magazine ``Hero of the Environment,'' and author of the
2020 book on the environment, Apocalypse Never, published by
HarperCollins.
---------------------------------------------------------------------------
\1\ Environmental Progress is an independent nonprofit research
organization funded by charitable philanthropies and individuals with
no financial interest in our findings. We disclose our donors on our
website: http://environmentalprogress.org/mission.
---------------------------------------------------------------------------
I will make four points in my testimony:
1. American farmers are world leaders in innovation, productivity,
and environmental protection.
2. Technological change and agricultural modernization will
significantly outweigh climate change in the U.S. and
around the world.
3. Vegetarianism is not important for protecting the environment or
reducing greenhouse gas emissions.
4. The U.S. should directly and through the World Bank and other
institutions help poor and developing nations to modernize
agriculture for economic development, environmental, and
public health reasons.
I will draw upon the best-available science as well as upon my
interviews with scientists to present the evidence supporting these
three claims and recommendation.
I. The American farmer Is a World Leader in Innovation, Productivity,
and Environmental Protection
Urbanization, industrialization, and energy consumption have been
overwhelmingly positive for human beings as a whole. From preindustrial
times to today, life expectancy extended from thirty to seventy-three
years.\2\ Infant mortality declined from 43 to 4 percent.\3\ From 1981
to 2015, the population of humans living in extreme poverty plummeted
from 44 percent to ten percent.\4\
---------------------------------------------------------------------------
\2\ James C. Riley, ``Estimates of Regional and Global Life
Expectancy, 1800-2001,'' Population and Development Review 31, no. 3
(2005), 537-543, accessed January 16, 2020, www.jstor.org/stable/
3401478; ``World Population Prospects 2019: Highlights,'' United
Nations, accessed January 14, 2020, https://www.un.org/development/
desa/publications/world-population-prospects-2019-highlights.html.
\3\ Max Roser, et al., ``Child & Infant Mortality,'' Our World in
Data, 2019, accessed January 16, 2020, https://ourworldindata.org/
child-mortality. The World series for 1800 to 1960 was calculated by
Max Roser on the basis of the Gapminder estimates of child mortality
and the Gapminder series on population by country. For each estimate in
that period a population weighted global average was calculated. The
2017 child mortality rate was taken from the 2019 update of World Bank
data.
\4\ ``PovcalNet: an online analysis tool for global poverty
monitoring,'' The World Bank, accessed January 16, 2020, http://
iresearch.worldbank.org/PovcalNet/home.aspx.
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Our prosperity is made possible by using energy and machines so
fewer and fewer of us have to produce food, energy, and consumer
products, and more and more of us can do work that requires greater use
of our minds and that even offers meaning and purpose to our lives.
The declining number of workers required for food and energy
production, thanks to the use of modern energy and machinery, increases
productivity, grows the economy, and diversifies the workforce. Former
farm workers who move to cities spend their money buying food,
clothing, and other consumer products and services, resulting in a
workforce and society that is wealthier and engaged in a greater
variety of jobs.
The human population growth rate peaked in the early 1960s
alongside rising life expectancy and declining infant mortality.\5\
Total population will peak soon.\6\ And thanks to rising agricultural
productivity, the share of humans who are malnourished declined from 20
percent in 1990 to 11 percent today, about 820 million people.\7\
---------------------------------------------------------------------------
\5\ Max Roser, Hannah Ritchie and Esteban Ortiz-Ospina, ``World
Population Growth,'' Our World In Data, May 2019, accessed January 16,
2020, https://ourworldindata.org/world-population-growth.
\6\ Max Roser, Hannah Ritchie and Esteban Ortiz-Ospina, ``World
Population Growth,'' Our World In Data, May 2019, accessed January 16,
2020, https://ourworldindata.org/world-population-growth.
\7\ For 1990 data: U.N. Food and Agriculture Organization,
``Undernourishment around the world,'' The State of Food Insecurity in
the World, 2006 (Rome: FAO, 2006), http://www.fao.org/3/a0750e/
a0750e02.pdf.
For 2018 data: FAO, ``Suite of Food Security Indicators,'' FAOSTAT,
accessed January 28, 2020, http://www.fao.org/faostat/en/#data/FS.
---------------------------------------------------------------------------
Farms and cities are thus deeply connected. Cities concentrate
human populations and leave more of the countryside to wildlife. Cities
cover just more than half a percent of the ice-free surface of the
[E]arth.\8\ Less than half a percent of Earth is covered by pavement or
buildings.\9\ At the same time, humankind's use of land for agriculture
is likely near its peak and capable of declining soon.\10\
---------------------------------------------------------------------------
\8\ Xiaoping Liu, et al., ``High-resolution multi-temporal mapping
of global urban land using Landsat images based on the Google Earth
Engine Platform,'' Remote Sensing of Environment 209 (2018): 227-239,
https://doi.org/10.1016/j.rse.2018.02.055.
\9\ Christopher D. Elvidge, et al., ``Global distribution and
density of constructed impervious surfaces,'' Sensors 7, no. 9 (2007):
1962-1979, https://dx.doi.org/10.3390%2Fs7091962.
\10\ Niko Alexandratos and Jelle Bruinsma, ``World agriculture
towards 2030/2050: the 2012 revision,'' Agricultural Development
Economics Division, Food and Agriculture Organization of the United
Nations, June 2012, accessed January 16, 2020, http://www.fao.org/3/a-
ap106e.pdf. The UN FAO projects that arable land and permanent crop
area will stay nearly flat through 2050, as detailed from its report on
the subject.
---------------------------------------------------------------------------
As wealthy nations develop and farms become more productive,
grasslands, forests, and wildlife are returning. Globally, the rate of
reforestation is catching up to a slowing rate of deforestation.\11\
The key is producing more food on less land. While the amount of land
used for agriculture has increased by eight percent since 1961, the
amount of food produced has grown by an astonishing 300 percent.\12\
---------------------------------------------------------------------------
\11\ FAO, ``Data,'' FAOSTAT, accessed October 26, 2019, http://
www.fao.org/faostat/en/#data. The FAO finds reforestation in Europe,
Asia, North America, and the Caribbean. Central America, South America,
Africa, and Oceania are still deforesting. The global rate of
deforestation has been cut by over half since 1990, from 7.3 million to
3.3 million hectares per year as reforestation accelerated.
\12\ Global FAO, ``Data,'' FAOSTAT, accessed October 26, 2019,
http://www.fao.org/faostat/en/#data. Per FAO, global per capita
kilocalorie production was 2196 in 1961, and 2884 in 2013. Along with
the population rise from 3.1 to 7.2 billion between 1961 and 2013,
global food production has tripled. Global land for agriculture
increased from 4.5 to 4.8 billion hectares over the same period
---------------------------------------------------------------------------
Though pastureland and cropland expanded 5 and 16 percent, between
1961 and 2017, the maximum extent of total agriculture land occurred in
the 1990s, and declined significantly since then, led by a 4.5 percent
drop in pasture land since 2000.\13\ Between 2000 and 2017, the
production of beef and cow's milk increased by 19 and 38 percent,
respectively, even as total land used globally for pasture shrank.\14\
---------------------------------------------------------------------------
\13\ Global FAO, ``Data,'' FAOSTAT, accessed October 26, 2019,
http://www.fao.org/faostat/en/#data.
\14\ Global FAO, ``Data,'' FAOSTAT, accessed October 26, 2019,
http://www.fao.org/faostat/en/#data.
---------------------------------------------------------------------------
The replacement of farm animals with machines massively reduced
land required for food production. By moving from horses and mules to
tractors and combine harvesters, the United States slashed the amount
of land required to produce animal feed by an area the size of
California. That land savings constituted an astonishing \1/4\ of total
U.S. land used for agriculture.\15\
---------------------------------------------------------------------------
\15\ USDA, Changes in Farm Production and Efficiency: A Summary
Report, Statistical Bulletin 233 (Washington, D.C.: USDA, 1959), 12-13.
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Today, hundreds of millions of horses, cattle, oxen, and other
animals are still being used as draft animals for farming in Asia,
Africa, and Latin America. Not having to grow food to feed them could
free up significant amounts of land for endangered species, just as it
did in Europe and North America.
Energy is required for all of this agricultural modernization.
Thanks to fertilizers, irrigation, petroleum-powered tractors, and
other farm machines, the power densities of farms rise ten-fold as they
evolve from the labor-intensive techniques used by small farmers in
poor nations to the energy-intensive practices used on California's
rice farms.\16\
---------------------------------------------------------------------------
\16\ Vaclav Smil, Power Density (Cambridge: The MIT Press, 2016),
168.
---------------------------------------------------------------------------
American farmers embraced the digital revolution starting in the
1990s. It was then that they started using GPS for auto-steering
combines and other farm machinery, significantly reducing both overlaps
and gaps in fields. Farmers mapped soils and used new equipment to
apply chemicals at precise and variable rates specific to different
soils. GPS also opened up precision agriculture, as it is called.
Special equipment can space seeds precisely, while genetic engineering
helps farmers guard against insects and weeds with fewer and less toxic
chemicals.
Conventional agriculture is used on 99 percent of U.S. cropland and
is responsible for significant environmental improvements to farming.
The total amount of pesticides applied to U.S. crops declined 18%
between 1980 and 2008 and is today 80 percent lower than their 1972
peak.\17\ Total fertilizer use in the U.S. peaked in 1981 and hasn't
risen since, despite an increase in total crop production of 44
percent, according to the Environmental Protection Agency.\18\
---------------------------------------------------------------------------
\17\ Jorge Fernandez-Cornejo, et al., ``Pesticide Use Peaked in
1981,'' USDA Economic Research Service, June 2, 2014. ers.usda.gov.
\18\ Environmental Protection Agency, ``Report on the
Environment,'' accessed February 18, 2021. www.epa.gov.
---------------------------------------------------------------------------
The use of water per unit of agricultural production has been
declining as farmers have become more precise in irrigation methods.
Irrigation water used per bushel of corn has declined by nearly half
since 1980, while greenhouse gases declined 31 percent.\19\
---------------------------------------------------------------------------
\19\ Field to Market, ``Environmental and Socioeconomic Indicators
for Measuring Outcomes of On-Farm Agricultural Production in the
U.S.,'' December 2016. www.field tomarket.org.
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High-yield farming is also better for soils. Eighty percent of all
degraded soils are in poor and developing nations of Asia, Latin
America, and Africa. The rate of soil loss is twice as high in
developing nations as in developed ones. Thanks to the use of
fertilizer, wealthy European nations and the United States have adopted
soil conservation and no-till methods, which prevent erosion. In the
United States, soil erosion declined 40 percent in just fifteen years,
between 1982 and 1997, while yields rose.\20\
---------------------------------------------------------------------------
\20\ USDA, ``Changes in Erosion 1982-1997,'' United States
Department of Agriculture, January 4, 2001, https://www.nrcs.usda.gov/
wps/portal/nrcs/detail/soils/ref/?cid=nrcs143_013911; FAO, ``Data,''
FAOSTAT, accessed January 27, 2020, http://www.fao.org/faostat/en/
#data. FAO data on crop yields show almost every major crop increasing
in yield in the United States between 1982 and 1997.
---------------------------------------------------------------------------
II. Technological Change and Agricultural Modernization Will
Significantly Outweigh Climate Change in the U.S. and Around
the World
In 2019 the Intergovernmental Panel on Climate change warned that
warming of 1.5 C above pre-industrial temperatures would cause ``long-
lasting or irreversible'' harm. The New York Times reported that
planetary warming threatens to worsen resource scarcity, and ``floods,
drought, storms and other types of extreme weather threaten to disrupt,
and over time shrink, the global food supply.'' \21\
---------------------------------------------------------------------------
\21\ Christopher Flavelle, ``Climate Change Threatens the World's
Food Supply, United Nations Warns,'' New York Times, August 8, 2019,
https://www.nytimes.com.
---------------------------------------------------------------------------
But there is little to no scientific basis for claims that climate
change will reduce agricultural productivity globally. ``It's difficult
to see how we could accommodate eight billion people or maybe even half
of that,'' said Swedish agronomist Johan Rockstrom of the Potsdam
Institute in Germany, if temperatures rise four or more degrees above
preindustrial levels.\22\ But when I asked Rockstrom by telephone for
the scientific studies supporting his claim, he said, ``I must admit I
have not seen a study.'' \23\
---------------------------------------------------------------------------
\22\ Gaia Vince, ``The Heat is On Over the Climate Crisis. Only
Radical Measures Will Work,'' Guardian, May 18, 2019, https://
www.theguardian.com.
\23\ Johan Rockstrom (director of the Potsdam Institute for Climate
Impact Research) in discussion with the author, November 27, 2019.
---------------------------------------------------------------------------
In fact, scientists have done that study--two are Rockstrom's
colleagues at the Potsdam Institute--and they found that food
production could increase even at 4 to 5 C warming above
preindustrial levels, and they found that technical improvements, such
as fertilizer, irrigation, and mechanization, mattered more than
climate change.\24\
---------------------------------------------------------------------------
\24\ Hans van Meijl, et al., ``Comparing impacts of climate change
and mitigation on global agriculture by 2050,'' Environmental Research
Letters 13, no. 6 (2018), https://iopscience.iop.org/article/10.1088/
1748-9326/aabdc4/pdf.
---------------------------------------------------------------------------
Food production would only decline in the U.S. and North America if
the American farmer stopped innovating and adapting, which is counter
to the nature of farmers. IPCC finds that there would be net
agricultural productivity declines ``without adaptation'' and that the
productivity of agriculture in some parts of North America will improve
with warmer temperatures. Some of the yield increases in recent decades
came from rising temperatures in Canada and greater precipitation in
the U.S. Where water is not a limiting factor, rising temperatures will
increase productivity in North America, unless farmers stop innovating
and adapting.\25\
---------------------------------------------------------------------------
\25\ Romero-Lankao, P., J.B. Smith, D.J. Davidson, N.S.
Diffenbaugh, P.L. Kinney, P. Kirshen, P. Kovacs, and L. Villers Ruiz,
2014: North America. In: Climate Change 2014: Impacts, Adaptation, and
Vulnerability. Part B: Regional Aspects. Contribution of Working Group
II to the Fifth Assessment Report of the Intergovernmental Panel on
Climate Change [Barros, V.R., C.B. Field, D.J. Dokken, M.D.
Mastrandrea, K.J. Mach, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O.
Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken,
P.R. Mastrandrea, and L.L. White (eds.)]. Cambridge University Press,
Cambridge, United Kingdom and New York, NY, USA, pp. 1444, 1462.
---------------------------------------------------------------------------
There is very good reason to believe that American farmers will
adapt well to climate change. ``The North American agricultural
industry has the adaptive capacity to offset projected yield declines
and capitalize on opportunities under 2 warming,'' IPCC writes,
including through genetically modified seeds. Many of these practices
bring other economic and environmental benefits. Low- and no-till
farming reduces soil erosion, allows for the retention of moisture, and
reduces greenhouse gases.\26\
---------------------------------------------------------------------------
\26\ Romero-Lankao, P., J.B. Smith, D.J. Davidson, N.S.
Diffenbaugh, P.L. Kinney, P. Kirshen, P. Kovacs, and L. Villers Ruiz,
2014: North America. In: Climate Change 2014: Impacts, Adaptation, and
Vulnerability. Part B: Regional Aspects. Contribution of Working Group
II to the Fifth Assessment Report of the Intergovernmental Panel on
Climate Change [Barros, V.R., C.B. Field, D.J. Dokken, M.D.
Mastrandrea, K.J. Mach, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O.
Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken,
P.R. Mastrandrea, and L.L. White (eds.)]. Cambridge University Press,
Cambridge, United Kingdom and New York, NY, USA, pp. 1463.
---------------------------------------------------------------------------
The U.S. Government's Fourth National Climate Assessment supports
IPCC's findings. It similarly suggests that the risks of climate change
to U.S. farmers will be mitigated by innovation and adaptation. Farmers
can adapt by changing what they produce, altering productive inputs
including seed type, and using new technologies. Farmers can alter crop
rotations, use different cover crops, and deploy irrigation. Farmers
can manage heat stress among life stock by changing breeds and diets,
providing shade, and altering patterns of feeding and reproduction. The
Assessment points to pest and disease management, climate forecasting
tools, and crop insurance as proven effective ways to reduce risk and
increase productivity and efficiency.\27\
---------------------------------------------------------------------------
\27\ US Global Change Research Program, U.S. Government, ``Fourth
National climate Assessment, Chapter 10: Agriculture and Rural
Communities,'' 2017.
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Human beings around the world today produce 25 percent more food
than we consume, and experts agree surpluses will continue to rise in a
warmer world so long as poor nations gain access to fertilizer,
irrigation, roads, and other key elements of modern agriculture.\28\
The FAO projects that even farmers in the poorest regions today, like
sub-Saharan Africa, may see 40 percent crop yield increases from
technological improvements alone.\29\ It concludes that food production
will rise 30 percent by 2050 except in a scenario it calls Sustainable
Practices is adopted, in which case it would rise 20 percent.\30\
---------------------------------------------------------------------------
\28\ United Nations Food and Agriculture Organization (FAO), The
future of food and agriculture--Alternative pathways to 2050 (Rome:
Food and Agriculture Organization of the United Nations, 2018), 76-77.
\29\ Food and Agricultural Association of the United Nations
(FAO), The future of food and agriculture--Alternative pathways to 2050
(Rome: United Nations, 2018), 76-77.
\30\ FAO, The future of food and agriculture--Alternative pathways
to 2050 (Rome: United Nations, 2018), accessed December 16, 2019,
http://www.fao.org/global-perspectives-studies/food-agriculture-
projections-to-2050/en.
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Roughly 40 percent of the planet has seen ``greening''--more forest
and other biomass growth--between 1981 and 2016. Some of this greening
is due to a reversion of former agricultural lands to grasslands and
forests, and some of it is due to deliberate tree planting,
particularly in China.\31\ This is even true in Brazil. While the
world's attention has been focused on the Amazon, forests are returning
in the southeast, which is the more economically developed part of
Brazil. This is due to both rising agricultural productivity and
environmental conservation.\32\
---------------------------------------------------------------------------
\31\ Jing M. Chen, et al., ``Vegetation structural change since
1981 significantly enhanced the terrestrial carbon sink,'' Nature
Communications 10, no. 4259 (October 2019): 1-7, https://
www.nature.com/articles/s41467-019-12257-8.pdf.
\32\ Alberto Barretto, et al., ``Agricultural intensification in
Brazil and its effects on land-use patterns: an analysis of the 1975-
2006 period,'' Global Change Biology 19 (2013): 1804-15, https://
doi.org/10.1111/gcb.12174. ``The significant reduction in deforestation
that has taken place in recent years, despite rising food commodity
prices, indicates that policies put in place to curb conversion of
native vegetation to agriculture land might be effective. This can
improve the prospects for protecting native vegetation by investing in
agricultural intensification.''
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Part of the reason the planet is greening stems from greater carbon
dioxide in the atmosphere, and greater planetary warming.\33\
Scientists find that plants grow faster as a result of higher carbon
dioxide concentrations. From 1981 to 2016, four times more carbon was
captured by plants due to carbon-boosted growth than from biomass
covering a larger surface of Earth.\34\
---------------------------------------------------------------------------
\33\ Jing M. Chen, et al., ``Vegetation structural change since
1981 significantly enhanced the terrestrial carbon sink,'' Nature
Communications 10, no. 4259 (October 2019): 1-7, https://
www.nature.com/articles/s41467-019-12257-8.pdf.
\34\ Jing M. Chen, et al., ``Vegetation structural change since
1981 significantly enhanced the terrestrial carbon sink,'' Nature
Communications 10, no. 4259 (October 2019): 1-7, https://
www.nature.com/articles/s41467-019-12257-8.pdf.
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All else being equal, it would be best for global temperatures to
remain stable. We should not want them to either rise or decline. The
reason is because we have built our civilization based on current
temperatures.
But all else isn't equal. The cause of climate change is rising
energy consumption, and that energy consumption has been necessary for
the 90 percent decline in natural disaster deaths, the 25 percent and
rising global food surplus, and the 30 percent decline in the global
burden of disease.
Some have suggested that climate change will make diseases like
COVID-19 more frequent or more severe, but the main factors behind the
novel-coronavirus pandemic had nothing to nothing to do with climate
change and everything to do with the failure of the Chinese regime to
protect public health.
Governments and farmers have known what ``biosecurity'' measures to
take for decades, and enacted them, partly, in response to the 2005
avian flu (H5N1) epidemic. These measures include hardened facilities
to prevent, for example, bats, from entering buildings; the regular
testing of animals and workers; and disallowing live animals from being
transported and sold at markets.\35\
---------------------------------------------------------------------------
\35\ ``Should We Domesticate Wild Animals to Prevent Disease
Pandemics? An Interview with Peter Daszak,'' Environmental Progress,
May 21, 2020.
---------------------------------------------------------------------------
Other scientists find similar outcomes. The UN Food and Agriculture
concludes that food production will rise 30 percent by 2050 unless
``sustainable practices'' are adopted--in which case it would rise just
10 to 20 percent.\36\ And a paper published in Nature in 2019 found
that ``agro-ecological'' farming, which has long been promoted by
European governments, U.S. NGOs, and the UN, does not improve the
agricultural productivity of small African farmers.\37\
---------------------------------------------------------------------------
\36\ United Nations Food and Agriculture Organization (FAO), The
future of food and agriculture--Alternative pathways to 2050 (Rome:
Food and Agriculture Organization of the United Nations, 2018), p. 76-
77.
\37\ Marc Corbeels, et al., ``Limits of conservation agriculture
to overcome low crop yields in sub-Saharan Africa,'' July 16, 2020. For
examples of efforts to promote agroecology see Shiny Varghese,
``Agroecological and other innovative approaches for sustainable
agriculture and food systems that enhance food security and
nutrition,'' Institute for Agriculture and Trade Policy, June 26, 2019.
---------------------------------------------------------------------------
In the summer of 2020, politicians and the news media pointed to
climate change as the cause of historic, high-intensity ``megafires''
in California and Oregon, but leading forest scientists said fire
suppression and the accumulation of wood fuel, not climate change, were
what made California's fires more intense.
``Climate dries the [wood] fuels out and extends the fire season
from 4-6 months to nearly year-round but it's not the cause of the
intensity of the fires,'' said U.S. Forest Service scientist Malcolm
North. ``The cause of that is fire suppression and the existing debt of
wood fuel.'' North estimates that there is five times more wood fuel in
California's forests, on average, than before Europeans arrived.
A large, well-managed forest turned a high-intensity fire into a
low-intensity one, proving that how forests are managed outweighs the
higher temperatures and longer fire season caused by climate change. In
2013, after a high-intensity megafire known as the Rim Fire in the
Stanislaus Forest reached Yosemite National Park, where prescriptive
burning had occurred, it became [1] a surface fire.
Similarly, the high-intensity Rough Fire of 2015 turned into a surface
fire after it reached Sequoia National Park, whose managers had been
using prescribed burns for decades.
---------------------------------------------------------------------------
\[1]\ https://fireecology.springeropen.com/articles/10.1186/s42408-
019-0041-0.
---------------------------------------------------------------------------
The evidence for the efficacy of what foresters call ``fuel
treatment,'' through selective logging, prescribed burning, or both,
can also be found on U.S. Forest Service lands. In 2014, areas where
there had been selective logging and prescribed burning survived the
high-intensity King megafire Eldorado National Forest. Similarly, the
2018 Carr fire burned through areas where there had been treatment of
wood fuels over the last 3 decades. Even so, areas that had prescribed
fire within the last 5 years, particularly the last 3 years, did
better. Such cases are powerful evidence that selective logging and
prescribed burning could allow many forests in California and elsewhere
to survive climate change.
III. Vegetarianism Is Not an Important Factor for Protecting the
Environment
In 2019, the Intergovernmental Panel on Climate Change (IPCC)
published a special report on food and agriculture. ``Scientists say
that we must immediately change the way we manage land, produce food
and eat less meat in order to halt the climate crisis,'' reported
CNN.\38\ Americans and Europeans need to reduce consumption of beef and
pork by 40 percent and 22 percent, respectively, said experts, in order
to feed ten billion people.\39\ If everyone followed a vegan diet,
which excludes not only meat but also eggs and dairy products, land-
based emissions could be cut by 70 percent by 2050, said IPCC.\40\
---------------------------------------------------------------------------
\38\ Isabelle Gerretsen, ``Change food production and stop abusing
land, major climate report warns,'' CNN, August 8, 2019, https://
www.cnn.com.
\39\ Jen Christensen, ``To help save the planet, cut back to a
hamburger and a half per week,'' CNN, July 17, 2019, https://
www.cnn.com.
\40\ Cheikh Mbow, et al., ``Food Security,'' in Valerie Masson-
Delmont, et al. (eds.), Climate Change and Land: an IPCC special report
on climate change, desertification, land degradation, sustainable land
management, food security, and greenhouse gas fluxes in terrestrial
ecosystems, IPCC, 2019, accessed January 21, 2020, https://www.ipcc.ch/
srccl.
---------------------------------------------------------------------------
But the headline number in the IPCC's 2019 report, a 70 percent
reduction in emissions by 2050, referred only to agricultural
emissions, which comprise a fraction of total greenhouse emissions.\41\
As such, converting to vegetarianism might reduce diet-related personal
energy use by 16 percent and greenhouse gas emissions by 20 percent,
found a study, but total personal energy use by just two percent, and
total greenhouse gas emissions by four percent.\42\
---------------------------------------------------------------------------
\41\ Cheikh Mbow, et al., ``Food Security,'' in Climate Change and
Land: an IPCC special report on climate change, desertification, land
degradation, sustainable land management, food security, and greenhouse
gas fluxes in terrestrial ecosystems (IPCC, 2019), 487
\42\ Janina Grabs, ``The rebound effects of switching to
vegetarianism. A microeconomic analysis of Swedish consumption
behavior,'' Ecological Economics 116 (2015): 270-279, https://doi.org/
10.1016/j.ecolecon.2015.04.030.
---------------------------------------------------------------------------
As such, were IPCC's ``most extreme'' scenario of global veganism
to be realized--in which, by 2050, humans completely cease to consume
animal products and all livestock land is reforested--total carbon
emissions would decline by just ten percent.\43\
---------------------------------------------------------------------------
\43\ Cheikh Mbow, et al., ``Food Security,'' in Climate Change and
Land: an IPCC special report on climate change, desertification, land
degradation, sustainable land management, food security, and greenhouse
gas fluxes in terrestrial ecosystems (IPCC, 2019), 487. In ``business-
as-usual'', global greenhouse emissions will rise to 86 gigatons/year
by 2050, and emissions from agriculture will rise to 11.6 gigatons/
year. The ``upper-bound'' scenario of 100 percent veganism would reduce
emissions by 8.1 gigatons/year from this baseline.
---------------------------------------------------------------------------
Another study found that if every American reduced her or his meat
consumption by \1/4\, greenhouse emissions would be reduced by just one
percent. If every American became vegetarian, U.S. emissions would drop
by just five percent.\44\
---------------------------------------------------------------------------
\44\ Gidon Eshel, ``Environmentally Optimal, Nutritionally Sound,
Protein and Energy Conserving Plant Based Alternatives to U.S. Meat,''
Nature: Scientific Reports 9, no. 10345 (August 8, 2019), https://
doi.org/10.1038/s41598-019-46590-1.
---------------------------------------------------------------------------
Study after study comes to the same conclusion. One found that, for
individuals in developed nations, going vegetarian would reduce
emissions by just 4.3 percent, on average.\45\ And yet another found
that, if every American went vegan, emissions would decline by just 2.6
percent.\46\
---------------------------------------------------------------------------
\45\ Elinor Hallstrom, et al., ``Environmental impact of dietary
change: a systematic review,'' Journal of Cleaner Production 91 (March
15, 2015), https://doi.org/10.1016/j.jclepro.201y4.12.008. The best
estimate of emissions reductions of going vegetarian was 540kg, while
average developed nation CO2e (Annex I) is 12.44t
CO2e.
\46\ Robin R. White and Mary Beth Hall, ``Nutritional and
greenhouse gas impacts of removing animals from U.S. agriculture,''
Proceedings of the National Academy of Sciences 114, no. 48 (2017),
https://doi.org/10.1073/pnas.1707322114.
---------------------------------------------------------------------------
Plant-based diets, researchers find, are cheaper than those that
include meat. As a result, people often end up spending their money on
things that use energy, like consumer products. This phenomenon is
known as the rebound effect. If consumers respent their saved income on
consumer goods, which require energy, the net energy savings would only
be .07 percent, and the net carbon reduction just two percent.\47\
---------------------------------------------------------------------------
\47\ Janina Grabs, ``The rebound effects of switching to
vegetarianism. A microeconomic analysis of Swedish consumption
behavior,'' Ecological Economics 116 (2015): 270-279, https://doi.org/
10.1016/j.ecolecon.2015.04.030.
---------------------------------------------------------------------------
None of this means that people in rich nations can't be persuaded
to change their diets. For example, since the 1970s, Americans and
others in developed nations have been eating more chicken and less
beef. The global output of chicken meat has grown fourteen-fold, from
eight metric megatonnes to 109 metric megatonnes, between 1961 and
2017.\48\
---------------------------------------------------------------------------
\48\ FAO, ``Livestock Primary,'' FAOSTAT, http://www.fao.org/
faostat/en/#data/QL.
---------------------------------------------------------------------------
The good news is that the total amount of land humankind uses to
produce meat peaked in the year 2000. Since then, the land dedicated to
livestock pasture around the world, according to the Food and
Agriculture Organization of the U.N., has decreased by more than 540
million square miles, an area 80 percent as large as Alaska.\49\
---------------------------------------------------------------------------
\49\ FAO, World Livestock: Transforming the livestock sector
through the Sustainable Development Goals (Rome: FAO, 2018), Licence:
CC BY-NC-SA 3.0 IGO, http://www.fao.org/3/CA1201EN/ca1201en.pdf.
---------------------------------------------------------------------------
All of this happened without a vegetarian revolution. Today, just
two to four percent of Americans are vegetarian or vegan. About 80
percent of those who try to become vegetarian or vegan eventually
abandon their diet, and more than half do so within the first year.\50\
---------------------------------------------------------------------------
\50\ Charles Stahler, ``How many people are vegan?'' Vegetarian
Resource Group, based on March 7-11, 2019 Harris poll, accessed
December 31, 2019, https://www.vrg.org/nutshell/Polls/
2019_adults_veg.htm; Kathryn Asher, et al., ``Study of Current and
Former Vegetarians and Vegans: Initial Findings, December 2014,''
Humane Research Council and Harris International, accessed October 30,
2019, https://faunalytics.org/wp-content/uploads/2015/06/
Faunalytics_Current-Former-Vegetarians_Full-Report.pdf.
---------------------------------------------------------------------------
Developed nations like the United States saw the amount of land
they use for meat production peak in the 1960s. Developing nations,
including India and Brazil, saw their use of land as pasture similarly
peak and decline.\51\ Part of this is due to the shift from beef to
chicken. A gram of protein from beef requires two times the energy
input in the form of feed as a gram from pork, and eight times a gram
from chicken.\52\ But mostly it is due to efficiency. Between 1925,
when the United States started producing chicken indoors, and 2017,
breeders cut feeding time by more than half while more than doubling
the weight.\53\
---------------------------------------------------------------------------
\51\ FAO, ``Land Use,'' FAOSTAT, accessed January 27, 2020, http://
www.fao.org/faostat/en.
\52\ A. Shepon, et al., ``Energy and Protein Feed-to-Food
Conversion Efficiencies in the U.S. and Potential Food Security Gains
from Dietary Changes,'' Environmental Research Letters 11, no. 10
(2016): 105002, https://doi.org/10.1088/1748-9326/11/10/105002. Beef
has a protein conversion efficiency of 2.5%, pork of 9%, and poultry of
21%.
\53\ Vaclav Smil, Should We Eat Meat? Evolution and Consequences of
Modern Carnivory (Oxford: John Wiley & Sons, Ltd., 2013), 92. When the
U.S. started producing chickens indoors, in 1925, it took 112 days for
one to reach maturity. By 1960 it took half as long and chickens gained
\1/3\ more weight. By 2017, chickens grown indoors only required just
48 days to reach maturity and they had more than doubled in weight
since 1925.
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Meat production roughly doubled in the United States since the
early 1960s, and yet greenhouse gas emissions from livestock declined
by 11 percent during the same period.\54\ Producing a pound of beef in
the U.S. today requires \1/3\ less land, \1/5\ less feed, and 30
percent fewer animals as the 1970s.\55\
---------------------------------------------------------------------------
\54\ FAO, ``Data,'' FAOSTAT, http://www.fao.org/faostat/en/#data/
RL, cited in Frank Mitloehner, ``Testimony before the Committee on
Agriculture, Nutrition and Forestry U.S. Senate,'' May 21, 2019,
accessed November 3, 2019, https://www.agriculture.senate.gov/imo/
media/doc/Testimony_Mitloehner_05.21.2019.pdf.
\55\ J.L. Capper, ``The environmental impact of beef production in
the United States: 1977 compared with 2007,'' Journal of Animal
Science, December 1, 2011.
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American cow milk production in the U.S. today requires 90 percent
as much land and 79 percent fewer animals as it did in 1944.\56\ Fewer
animals means \2/3\ less methane, a potent greenhouse gas, per glass of
milk today as compared to 1950.\57\
---------------------------------------------------------------------------
\56\ J.L. Capper, et al, ``The environmental impact of dairy
production: 1944 compared with 2007,'' Journal of Animal Science, June
2009.
\57\ Frank Mitloehner, ``Testimony before the committee on
agriculture nutrition and forestry U.S. Senate,'' May 21, 2019.
---------------------------------------------------------------------------
Last fall I visited a milking operation owned by Matt Swanson near
Turlock, California. I was amazed as I watched dozens of cows calmly
eat and get milked as they slowly turned on a giant merry go-round. The
machine was labor-saving, allowing for under a half dozen workers to
oversee an operation with hundreds of milking cows.
IV. The U.S. Should Directly and Through the World Bank and Other
Institutions Help Poor and Developing Nations To Modernize
Agriculture for Economic Development, Environmental, and Public
Health Reasons
The use of land as pasture for beef production is humankind's
single largest use of Earth's surface. We use twice as much land for
beef and dairy production as for our second largest use of Earth, which
is growing crops. Nearly half of Earth's total agricultural land area
is required for ruminant livestock, which includes cows, sheep, goats,
and buffalo.\58\
---------------------------------------------------------------------------
\58\ FAO, ``Land Use'' FAOSTAT, 2017, http://www.fao.org/faostat/
en/#data/RL.
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During the last 300 years, an area of forests and grasslands almost
as large as North America was converted into pasture, resulting in
massive habitat loss and driving the significant declines in wild
animal populations. Between 1961 and 2016, pastureland expanded by an
area almost the size of Alaska.\59\
---------------------------------------------------------------------------
\59\ FAO, ``Land Use,'' FAOSTAT, accessed January 27, 2020, http://
www.fao.org/faostat/en. To be exact, 1.42 million km2.
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While people in developing countries increased their per capita
meat consumption from 10 kilograms per year to 26 kilograms between
1964 to 1999, people in the Congo and other Sub-Saharan African nations
experienced no change in per capita meat consumption.\60\
---------------------------------------------------------------------------
\60\ World Health Organization, ``Availability and changes in
consumption of meat products,'' accessed January 23, 2020, https://
www.who.int/nutrition/topics/3_foodconsumption/en/index4.html.
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Activists argue that factory farms are far worse for the natural
environment than free-range beef, but pasture beef requires fourteen to
nineteen times more land per kilogram than industrial beef, according
to a review of fifteen studies.\61\ The same is true for other inputs,
including water. Highly efficient industrial agriculture in rich
nations requires less water per output than small farmer agriculture in
poor ones.\62\ Pasture beef generates 300 to 400 percent more carbon
emissions per kilogram than industrial beef.\63\
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\61\ Durk Nijdam, Geertruida Rood and Henk Westhoek, ``The price of
protein: Review of land use and carbon footprints from life cycle
assessments of animal food products and their substitutes,'' Food
Policy 37 (2012): 760-770, https://doi.org/10.1016/
j.foodpol.2012.08.002.
\62\ David Gustafson, et al., ``Climate adaptation imperatives:
Global sustainability trends and eco-efficiency metrics in four major
crops--canola, cotton, maize, and soybeans,'' International Journal of
Agricultural Sustainability 12 (2014): 146-163, https://doi.org/
10.1080/14735903.2013.846017.
\63\ Durk Nijdam, Geertruida Rood and Henk Westhoek, ``The price of
protein: Review of land use and carbon footprints from life cycle
assessments of animal food products and their substitutes,'' Food
Policy 37 (2012): 760-770, https://doi.org/10.1016/
j.foodpol.2012.08.002.
``Production of 1 kg of extensively farmed beef results in roughly
three to four times as many greenhouse gas emissions as the equivalent
amount of intensively farmed beef.''
---------------------------------------------------------------------------
This difference in emissions comes down to diet and lifespan. Cows
raised at industrial farms are typically sent from pastures to feedlots
at about 9 months old, and then they are sent to slaughter at fourteen
to eighteen months. Grass-fed cattle spend their entire lives at
pasture and aren't slaughtered until between eighteen to twenty-four
months of age. Since grass-fed cows gain weight more slowly and live
longer, they produce more manure and methane.\64\
---------------------------------------------------------------------------
\64\ Lupo, C.D., Clay, D.E., Benning, J.L., & Stone, J.J. (2013).
Life-Cycle Assessment of the Beef Cattle Production System for the
Northern Great Plains, USA. Journal of Environment Quality, 42(5),
1386. doi:10.2134/jeq2013.03.0101
---------------------------------------------------------------------------
In addition to their longer lifespans, the roughage-heavy diets
typical of organic and pasture farm systems result in cows releasing
more methane. These facts combined tell us that the global warming
potential of cows fed concentrates is 4 to 28 percent lower for cows
fed roughage.\65\
---------------------------------------------------------------------------
\65\ M. de Vries, C.E. van Middelaar, and I.J.M. de Boer,
``Comparing environmental impacts of beef production systems: A review
of life cycle assessments,'' Livestock Science 178 (August 2015): 279-
288, https://doi.org/10.1016/j.livsci.2015.06.020.
---------------------------------------------------------------------------
Attempting to move from factory farming to organic, free-range
farming would require vastly more land, and thus destroy the habitat
needed by endangered species. ``You simply can't feed billions of
people free-range eggs,'' a farmer told a journalist. ``It's cheaper to
produce an egg in a massive laying barn with caged hens. It's more
efficient and that means it's more sustainable'' \66\
---------------------------------------------------------------------------
\66\ Jonathan Safran Foer, Eating Animals (New York: Little Brown,
2009), 95-96.
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Modernized agricultural techniques and inputs could increase rice,
wheat, and corn yields five-fold in sub-Saharan Africa, India, and
developing nations.\67\ Experts say sub-Saharan African farms can
increase yields by nearly 100 percent by 2050 simply through access to
fertilizer, irrigation, and farm machinery.\68\
---------------------------------------------------------------------------
\67\ A. Bala, ``Nigeria,'' Global Yield Gap and Water Productivity
Atlas, accessed January 16, 2020, http://www.yieldgap.org/en/web/guest/
nigeria; Nikolai Beilharz, ``New Zealand farmer sets new world record
for wheat yield,'' ABC News, April 3, 2017, https://www.abc.net.au;
Matthew B. Espek, et al., ``Estimating yield potential in temperate
high-yielding, direct-seeded U.S. rice production systems,'' Field
Crops Research 193 (2016): 123-132, https://doi.org/10.1016/
j.fcr.2016.04.003. While average yields for some crops like wheat have
plateaued, there is still more room for them to increase. In 2017, a
farmer in New Zealand produced an astonishing eight times more wheat
than the Australian average, and five times more than the global
average.
\68\ FAO, The future of food and agriculture--Alternative pathways
to 2050 (Rome: Food and Agriculture Organization of the United Nations,
2018), 76-77.
---------------------------------------------------------------------------
If every nation raised its agricultural productivity to the levels
of its most successful farmers, global food yields would rise as much
as 70 percent.\69\ If every nation increased the number of crops per
year to their full potential, food crop yields could rise another 50
percent.\70\
---------------------------------------------------------------------------
\69\ Nathaniel D. Mueller, et al., ``Closing yield gaps through
nutrient and water management,'' Nature 490 (2012): 254-257, https://
doi.org/10.1038/nature11420.
\70\ Deepak K. Ray, ``Increasing global crop harvest frequency:
recent trends and future directions,'' Environmental Research Letters 8
(2013), https://doi.org/10.1088/1748-9326/8/4/044041.
---------------------------------------------------------------------------
The most efficient meat production in North America requires twenty
times less land than the most efficient meat production in Africa.
Replacing wild animal meat with modern meats like chicken, pork, and
beef would require less than one percent of the total land used
globally for farming.\71\
---------------------------------------------------------------------------
\71\ World average yield for chicken 14 m2/kg, pork
17m2/kg, and 43 m2/kg for beef.
John E. Fa, Carlos A. Peres and Jessica J. Meeuwig, ``Bushmeat
Exploitation in Tropical Forests: an Intercontinental Comparison,''
Conservation Biology 16 (2002): 232-237, https://doi.org/10.1046/
j.1523-1739.2002.00275.x.
5 million tons of bushmeat extracted in the Congo and Amazon
basins.
Emiel V. Elferink and Sanderine Nonhebel, ``Variations in land
requirements for meat production,'' Journal of Cleaner Production 15,
no. 18 (2007): 1778-1786. https://doi.org/10.1016/
j.jclepro.2006.04.003.
---------------------------------------------------------------------------
The technical requirements for creating what experts call ``the
livestock revolution'' are straightforward. Farmers need to improve
breeding of animals, their diet, and the productivity of grasses for
foraging. Increasing meat production must go hand-in-hand with
increasing agricultural yields to improve and increase feed. In
Northern Argentina, farmers were able to reduce the amount of land used
for cattle ranching by 99.7 percent by replacing grass-fed beef with
modern industrial production.\72\
---------------------------------------------------------------------------
\72\ Ricardo Grau, Nestor Gasparri, and T. Mitchell Aide,
``Balancing food production and nature conservation in the subtropical
dry forests of NW Argentina,'' Global Change Biology 14, no. 5 (2008):
985-997, https://doi.org/10.1111/j.1365-2486.2008.01554.x.
---------------------------------------------------------------------------
The dominant form of climate policy in international bodies and
among nations around the world emerged from 1960s-era environmental
policies aimed at constraining food and energy supplies. These policies
are correctly referred to as Malthusian in that they stem from the
fears, first articulated by the British economist Thomas Malthus in
1798, that humans are at constant risk of running out of food.
Real world experience has repeatedly disproven Malthusianism. If it
hadn't, there wouldn't be nearly eight billion of us. Worse, Malthusian
ideas have been used to justify unethical policies that worsen
socioeconomic inequality by making food and energy more expensive,
including closing down nuclear plants.\73\
---------------------------------------------------------------------------
\73\ Michael Shellenberger, Apocalypse Never: Why Environmental
Alarmism Hurts Us All, HarperCollins, 2020, p. 222-249.
---------------------------------------------------------------------------
The same report which found that agricultural modernization
outweighs climate change also found that climate policies were more
likely to hurt food production and worsen rural poverty than climate
change itself. The ``climate policies'' the authors refer to are ones
that would make energy more expensive and result in more bioenergy use
(the burning of biofuels and biomass), which in turn would increase
land scarcity and drive up food costs. The IPCC comes to the same
conclusion.\74\
---------------------------------------------------------------------------
\74\ ``This occurs because . . . land-based mitigation leads to
less land availability for food production, potentially lower food
supply, and therefore food price increases.'' Cheikh Mbow, et al.,
``Chapter Five: Food Security,'' in V. Masson-Delmotte, et al., eds.,
Climate Change and Land: an IPCC special report on climate change,
desertification, land degradation, sustainable land management, food
security, and greenhouse gas fluxes in terrestrial ecosystems (IPCC,
2019), https://www.ipcc.ch/site/assets/uploads/2019/11/SRCCL-Full-
Report-Compiled-191128.pdf.
---------------------------------------------------------------------------
Policymakers should explicitly reject policies that significantly
raise food and energy prices, directly or indirectly. Republicans and
Democrats alike should affirm their commitment to human flourishing and
prosperity, both of which depend on cheap food and energy, which depend
on the rising productivity of inputs to agriculture and electricity
generation, including labor, land, and capital.
But we should go beyond that and seek to help our brothers and
sisters in poor nations to modernize agriculture, industrialize, and
modernize their economies, for economic and environmental reasons. Such
a partnership will be good for America and good for the planet.
Thank you for inviting my testimony.
Attachment
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]
The Chairman. Thank you. Thank you very much. Thank each of
you very much.
And now, we are going to open it up for questions at this
time, and Members will be recognized for questions in order of
seniority, alternating between Majority and Minority Members.
Each Member will be recognized for 5 minutes each, in order to
allow us to get in as many questions as we can.
I want to start by just stressing the importance of we in
agriculture--this hearing has been put together to address all
of the impacts with climate change, but to make sure that we
are addressing climate change directly as it impacts
agriculture and our food security first.
And so, let me start with you, Mr. Brown. You were featured
in the documentary, Kiss the Ground, and in that clip that we
just saw, the narrator spoke of a simple solution for many of
the climate changes we are experiencing, and that is what we
are looking for today at this hearing: solutions. And what that
announcer said was this, and I quote, ``The solution is right
under our feet.''
Can you unpack that for us?
Mr. Brown. I sure can. Thank you, Mr. Chairman.
The solution is under our feet. That solution is biology,
and it is regenerative agriculture. The way this works is that
living plants take in sunlight through photosynthesis. They
bring in the carbon out of the atmosphere through
photosynthesis. They produce all these compounds, and then they
pump that into the soil.
Studies have shown, Dr. Teague in 2016 showed that we can
sequester over \1/2\ of the carbon emissions annually in the
U.S. through regenerative agriculture, through using these six
principles that I laid out. This is not rocket science. It is
simply using time-tested ecological principles to heal our
planet.
The Chairman. Now, let me ask you this, because I have been
working very intimately with our farming interests, and there
are two that come to mind. And I was wondering if this is an
example of what you are talking about. One is with Bayer. Bayer
has developed sequestration regeneration--and something called
no-till farming, I believe. But at any rate, what they are
doing is partnering with the farmers to get the solution that
goes to your point, it is in the ground. It is there.
Agriculture is agriculture for two reasons: the water coming
from the heavens, and the carbon in the ground. Everything
comes from that.
And so, I wanted your opinion on what Bayer is doing, and I
found out yesterday that some of my friends in the peanut
industry are doing something similar. So, my point is, is this
the kind of thing that other interests in our farming sectors
should be doing?
Mr. Brown. Mr. Chairman, we all need to work together to
further these practices of regenerative agriculture. No-till
farming first came to the United States in 1962. We have only
approximately 25 percent of the agricultural cropland today in
no-till systems. No-till is a small piece of the puzzle, but we
have to do much more than that. We have to keep the soil
covered. We have to grow diverse cash crops, diverse cover
crops, and then we have to integrate livestock onto those
systems.
Yes, Bayer and other companies such as General Mills, are
doing good things by partnering with farmers and ranchers. This
needs to continue. It needs to be all of society coming
together for the betterment of all.
The Chairman. Okay. I am going to end there, because I want
to make sure we get our Members in, as many as we can.
I will yield to you, Ranking Member Thompson.
Mr. Thompson. Mr. Chairman, thank you. Thank you to all
five witnesses. All five of you, just great testimony. It just
reaffirms, very frankly, what you are talking about are the
things that this Committee has been dedicated to.
I think at least 5 or 6 years ago, it was this Committee
that had the first hearing on healthy soils in Washington. So,
in terms of regenerative practices, it was just very
reaffirming we have been doing the right things for a number of
years with the Agriculture Committee.
Great to see my friend, Zippy Duvall.
Mr. Cantore, you probably don't remember, but you were in
my district at the Weather Museum when you were honored in the
Weather Hall of Fame in Punxsutawney, Pennsylvania. That is
where we first met, and it is great to have you here with us
today.
I am interested in working with solutions. The Biden
Administration and the inside the Beltway think tanks are
pushing a climate agenda, suggesting new and shiny programs.
However, when I hear from the farmers about climate solutions--
and that is what we should be focused on, is climate solutions.
That should be the term that we use. They talk about the needs
for research, more boots on the ground, access to precision
agriculture, healthy soil practices, and the need for broadband
connectivity to support this technology.
Now, this all sounds like assistance available within the
farm bill programs that are there. Not to say that we can't
improve upon them, but it is a great base for addressing really
effective climate solutions, continuing those.
My question is simple. I will tee it up. I would love to
get a response within the time I have from as many of you as
possible. Is the solution as simple as doubling down on these
proven programs? Why don't we start with Mr. Shellenberger?
Mr. Shellenberger. Yes, thank you for the question.
Absolutely. I mean, we should continue to do what we have
been doing. There has been a case made for expanded investment
in research and development. Research and development works
best when it is problem-focused, when it is trying to solve
particular problems. We have terrific history through our
agricultural extension programs of working with American
farmers to improve yields.
So, yes, absolutely I think we should be continuing with
what is working, rather than changing course into something
really different, particularly you sometimes see proposals from
the environmental community that would result in lower yields
per unit of land, lower efficiencies. I think that would be a
huge mistake. Anything that can get us to greater efficiencies
and greater productivity is also going to be important for
adapting to climate change.
Mr. Thompson. Thank you. Thank you, Mr. Shellenberger.
President Duvall, great to be with you yesterday, and good
to see you virtually today.
Mr. Duvall. It is good to see you, too. I appreciate the
opportunity to be with you today.
The Committee has worked in the right direction. If you
just look at how much we have improved productivity
efficiencies, and even here on my farm here, I hear people talk
about agriculture destroying the climate. You could look at my
farm versus where my grandfather had it. I can show you
evidence of gulleys in the forestland that is around my farm
from bad conservation practices back then, and now over
several, several decades, my dad's life and my life, we have
improved it. It is all grassland. There are no gulleys anymore
in the fields. We are sequestering carbon. We are making sure
that we are putting animal manure with GPS. We are using
comprehensive nutrient management plans. All those things were
done through some of the programs at USDA. We are heading in
the right direction. We just need partners to help us move
forward.
I am concerned, if you look at the research dollars that we
invest in our country versus the rest of the world, I am told
that we are running behind on that. We need more research
dollars so that we can have the new technologies and untie our
hands. Give us a way to get the regulatory system streamlined
so that these new products can get to the field faster, so that
we can continue to be part of the solution to the problem.
Mr. Thompson. Thanks, Zippy.
Mr. Brown, congratulations on what you have been able to do
on those 5,000 acres. I have also been on farms where I have
seen the evidence of regenerative or healthy soil practices,
and just right over the line, the comparison.
I have only got a few seconds left, but I will yield to you
for any additional responses.
Mr. Brown. Mr. Ranking Member, thank you, and yes, the
agencies such as NRCS have done a good job, but we need to do
much more in the way of education. We have to educate farmers
and ranchers as to these time-tested ecological principles in
order to move it forward.
It is an absolute travesty that right now, we have such a
small amount of our landscape covered with cover crops. I fly
extensively, and you fly anywhere, the amount of bare soil we
see is absolutely appalling. There is no reason for that. We
need to do more and work with these agencies to further
education. Thank you.
Mr. Thompson. Thank you. Thank you, Mr. Chairman.
The Chairman. Thank you.
I would like to take this opportunity to insert a statement
from the National Association of State Departments of
Agriculture, NASDA, for the record. NASDA's statement supports
the expansion of Federal tools that incentivize climate smart
practices.
[The statement is located on p. 326.]
The Chairman. And now, I would like to recognize Mr. Costa
from California. You are recognized for 5 minutes. Is he not
there? Mr. Costa, are you there? Are you on mute?
Mr. Costa. I am unmuted now.
The Chairman. Wonderful.
Mr. Costa. Can you hear me?
The Chairman. You are now recognized, Mr. Costa.
Mr. Costa. Thank you. Thank you, Mr. Chairman.
Congratulations on the first Committee hearing, and I look
forward to working with you.
I think this is an excellent topic to begin, climate change
and the agricultural economy in our country. America has led
the way in so many areas, as many of our witnesses have just
testified for.
I am reminded, as we discuss how we become even more
productive and more creative, about a few facts. Some of us
remember the old television series, Dragnet, and Sergeant
Friday used to say, ``Just the facts, ma'am.'' Right? Well, the
facts are the following. Food is a national security issue, and
less than five percent of America's population are directly
involved in the production of food and fiber.
We have had an amazing change over the last 100 years. I am
a third-generation farmer, but I don't farm the same way my
parents did, nor my grandparents. And it continues to evolve
with technology and innovation.
Another fact: 200 years ago, we had 1\1/2\ billion people
on the plant. A few years ago, we just clicked over seven
billion people on the planet in less than 200 years. Climate
change has been occurring throughout the history of our planet.
The real question is, how much are we contributing to it?
Well, I will tell you that in 200 years, we have gone from
1.5 to over seven billion people. We are putting a lot more
stuff in the air, a lot more stuff in the water, and we are
having an impact. As a matter of fact, in 2006, I went with the
National Academies of Science--I don't know if you can see
this--to the South Pole for a week. This is a little vial that
calls itself the cleanest air on Earth, but it also shows using
isotope measuring from 1955 to 2006 that the CO2
emissions have increased by over 300 percent. Obviously, we are
having an impact, and American agriculture can play an
important role, as has been cited by the statistics that have
already been put out there. Because it matters.
California, where I come from, where we have been farming
for three generations in the San Joaquin Valley, is
experiencing drought conditions again, on the heels of the
worst drought that we had in the recorded history from 2012 to
2017. Our snow packs that we depend upon are becoming less
plentiful, as well as the rainfall. Ninety-nine percent of
California's agriculture, the number one agriculture state in
the nation, is irrigated. We have an imbalance between
overdrafting our groundwater.
But I firmly believe that with science and our
productivity, we can address these issues. The ingenuity of
America's farmers, ranchers, dairymen and -women have played a
big part in increasing our production and the quality of our
food. From healthy soils programs to state water efficiency
enhancement programs, alternative manure management, and
research and technical assistance that is occurring all around
the country, not just in California.
And by the way, I am a big believer in not reinventing the
wheel. Our ag universities across the country, whether it is
Texas A&M, whether it is the University of Georgia, whether it
is Purdue, whether it is UC Davis or Fresno State, where I come
from. There is a lot of good stuff going on that we ought to
combine in terms of research and development and innovation
with public and private partnerships.
Let me just talk about sustainability and talk to you,
Zippy, because you and I are both farmers, and you said it and
I have said it. Farmers are stewards of the land. So,
sustainability is a critical role.
Can you talk about--I think this infrastructure package and
the efforts that the Administration wants to deal with climate
change is an opportunity, and I think we should look at as an
opportunity, not only with existing farm programs, but how we
can provide incentives to do the right thing to increase our
productiveness. You are leading a conservation program and a
climate change effort. How do you think we can combine these
efforts?
Mr. Duvall. Well, I think that if you are talking about the
leadership that we provided to create the Food and Agriculture
Climate Alliance, we talk about those three principles that I
mentioned in my testimony of making sure that they are
supported--we support voluntary market incentive-based
programs, like some that we have, and to find new ones through
research. We want to advance the science-based outcomes----
The Chairman. Thank you.
Mr. Duvall.--of it, and then, of course, all of us are very
interested in the resilience in our rural communities and what
we can do there.
But it all boils down to broadband, which is part of our
infrastructure, and research and development.
Mr. Costa. Mr. Chairman, I have run out of time, but I
think it would be helpful if our witnesses, and Zippy, with
your effort, if you can write to the Committee about the
mission and development of your coalition, and share some of
the policy principles that the coalition sees as a fundamental
way in which we address climate change, and look at combining
the efforts with this infrastructure package to plus up these
incentive-based programs and farm programs that exist today,
and new things we might look at.
Mr. Duvall. Yes, sir, we can do that.
Mr. Costa. Thank you.
The Chairman. Thanks to both of you there.
Now moving on, I will now recognize Mr. Austin Scott of
Georgia. You are recognized for 5 minutes.
Mr. Austin Scott of Georgia. Thank you to my good friend,
Chairman Scott, and to Ranking Member Thompson.
I know that the title of the hearing is based on climate
change, but when we talk about this, candidly, we are talking
about environmental policy as a whole, and we are talking about
habitat, we are talking about water. And the better we are at
taking care of the land, the better the land will take care of
us. I will tell you, I think we can and we should do a better
job with the environment, and I look forward to being a part of
that further discussion.
One of the things that I will tell you bothers me is that
when I see forestlands being cut down and solar panels being
put up, when clearly there is new technology today that will do
a better job of providing carbon-free or extremely limited
carbon emission electricity. I think that one of the things
that we should look at is just the facts surrounding where the
tax credits are going with regard to that aspect of
environmental policy. I recognize that comes through a
different committee, but again, I want us to be reminded that
it is environmental policy as a whole that we have to focus on,
and not just agriculture with regard to climate change.
The other thing I want to do is say a big thank you to Ms.
Knox. When Hurricane Michael hit the State of Georgia, as you
know, it was devastating to the 2nd and the 8th Districts. Had
it not been for the University of Georgia and the other land-
grant institutions, through their research and extension
programs that provided the information to Chairman Scott and
Chairman Bishop and myself, then we would have not been able to
get the additional funds for the relief from Hurricane Michael
for our producers. And so, a big thank you to Ms. Knox. I know
you are doing a lot of great work down there on water
conservation and other things in my hometown of Tipton, and
where the National Environmentally Sound Production Agriculture
Lab is. I would certainly invite all of my colleagues on the
Agriculture Committee to make a trip down there to see all of
the great work that is going on at NESPA.
Mr. Cantore, thank you so much for your coverage of
Hurricane Michael, and what was happening to our farmers during
that storm. The losses were astronomical, and it was your
coverage that actually helped share our pain with the rest of
America, and their sympathy and their prayers were much
appreciated. I appreciate your coverage there.
With that said, Zippy, we have been friends a long time. We
rewrote the WHIP program with Hurricane Michael. It didn't work
as well as we had hoped it would. What suggestions do you have
for how the Agriculture Committee can improve the WHIP program
as we push forward?
Mr. Duvall. Well, Congressman, we have been friends a long
time, and I very much appreciate the friendship. Of course,
every time we have a disaster, it looks like it is a scurry on
the Hill to try to get the help out to the farmers.
Unfortunately, even though the amount of money that was finally
delivered to Georgia, it was 18 months, 2 years later, and a
lot of our farmers had already suffered the deadly consequence
of it and they lost their businesses and their farms, and
weren't able to continue farming. So, we have to find some way
to fast track, whether it be set aside special funding for it
with certain restrictions around it, make sure it doesn't get
misused. But it needs to be readily available when these
disasters hit across our country.
Mr. Austin Scott of Georgia. Mr. Duvall, I agree with you,
and one of the concerns I have is that if money that is
currently set aside for our ag producers, which candidly is a
very small percentage of the budget, when it is the largest
portion of the economy in most of the states. I don't want to
see that money moved into environmental policy. And again, that
is coming from someone who thinks that we can and should take
better care of the environment. And so, the concept of moving
the $30 billion to environmental policy bothers me. The concept
of doing anything with the carbon bank without an increase in
the CCC bothers me.
In my last few minutes, I want to say this. Mr. Brown,
there is a lot of great work at Fort Valley State University
with ruminants, and so, I hope you are benefitting from that. I
do want you to know, respectfully, crop insurance is and it has
to remain a risk management tool available for our farmers, and
if a producer has a history of higher yields and lower losses,
then they are rewarded with a higher average production history
and increased amount of coverage at lower premiums. And so, if
you have suggestions on how we improve it, I certainly am open
to suggestions of it. But I will just tell you, production
agriculture can't survive without some type of crop insurance
program that rewards good farm practices. And so, that not only
gets the environmental practices, but it gets the production
practices as well. And so, I am open to suggestions on how to
improve it. I thought we did a pretty good job in the 2018 Farm
Bill to encourage people to adopt conservation measures, but I
am not open to getting rid of the crop insurance program.
Mr. Chairman, my time has expired, I know, but I
appreciate, again, everybody for their work on this, and again,
Hurricane Michael taught all of us from Georgia and Florida big
lessons on the value of insurance and the environment, and we
can and we should do a better job.
With that, I yield back.
The Chairman. And I just want to recognize also those words
that you said, and also take a moment to compliment you in
helping provide the leadership for us after Michael. And you so
eloquently stated that Georgia was slammed, and thank you,
Austin, for pulling together. We went together, you, Mr.
Sanford Bishop, and myself, got money down there. So, we want
to thank you, and the young lady from the University of
Georgia.
Now, I will recognize Mr. McGovern, the gentleman from
Massachusetts, for 5 minutes. You may need to unmute. Oh, he
is? Can we get one of our technicians? He's on? Good. All
right. We will get working on it. Jim, they should get it
cleared momentarily.
Mr. McGovern. Can you hear me now?
The Chairman. Yes, I hear you a little.
Mr. McGovern. Okay. All right.
The Chairman. I hear you.
Mr. McGovern. All right.
The Chairman. Go ahead, Jim.
Mr. McGovern. All right. First of all, let me just say
thank you, Chairman Scott, for organizing this hearing. I think
it is a long overdue conversation, and I want to take just a
moment to underscore the sense of urgency that we should all be
feeling.
We have an extremely narrow window to limit warming to
1.5 C to avoid the most devastating impacts of climate change,
full stop. That means we need to achieve net zero emissions
across our entire economy, including agriculture, and it means
we need to prepare our farmers for the impacts of even the
best-case scenario of 1.5. That level of warming will still be
hugely consequential, and it is already happening.
Now, this might be news to some of my colleagues, but it is
not news to farmers. Farmers are not the ones who got us into
this mess, but now, they are on the frontlines of the climate
crisis. We need to think big to help them build resilience into
everything that they do, and we need to ensure that they have a
seat at the table.
Now, Mr. Brown, I want to thank you for sharing your story
of making ecological balance the heart of land stewardship. I
think there are both economic and ecological benefits that can
be achieved here, and I am reminded of the work that went into
developing standards for organic producers, which was a
collaborative process. Many organic producers live by the
practice you mentioned, while adhering to strict program
standards. When farmers transition to organic, they are taking
a risk, but having standards means that they have a roadmap and
a path to building consumer trust.
I want to make sure that we are providing real guidance and
real support to farmers who are eager to follow your example. I
think we need to have a roadmap that has integrity. So, could
you please discuss what work lies ahead to develop standards
for adopting regenerative techniques that will produce clarity
to both farmers and consumers? Again, organic farming is good
for the environment, and consumers have confidence in it
because of the standards. I wonder if you could respond with
your thoughts to that question.
Mr. Brown. Thank you, Representative McGovern.
First, I need to just briefly jump back and address--there
was a couple prior questions that were brought up that I did
not get a chance to answer.
Representative Costa talked about the need to sustain what
we are doing and to be sustainable. I am sorry, but I have
spent a great deal of time in the Central Valley of California,
and with all due respect, that is some of the most degraded
land in the United States. Do any water infiltration test
there, and you will see how degraded those soils are.
Representative Scott, I did not at all say we needed to end
crop insurance. That is not what I said at all. I simply said
that we need to make it outcome-based, and that outcome cannot
be solely yield, because yield comes at a detriment to the
environment. We also have to realize that in regenerative
agricultures, we increase the amount of nutrient-dense food
grown per acre. There is a misconception out there that
regenerative practices mean less yield. That is not at all
true. I produce now literally 30 times as much nutrient-dense
food per acre than I did before I started these regenerative
practices.
Now, Mr. McGovern, to answer your question. Yes, we do need
standards. The business that I work for, Understanding Ag, we
work with a lot of organic producers leading them down this
path. Organic is good, but we can do better because we can
minimize the amount of tillage that they are doing. We can also
increase diversity, increase the use of cover crops, produce
more nutrient-dense food, and then through Acts such as the
PRIME Act, we will be able to add value to the goods that they
are producing. Regenerative agriculture is a time-tested,
proven pathway to heal not only our land in respect to climate
change, but we can heal our communities, the profitability on
our farms and ranches, water quality, water quantity issues,
and many of the other things that we are currently facing as a
challenge in society today.
Mr. McGovern. Thank you. I appreciate your answer very
much.
I think my time is up, but I just think it is important for
all of us here to be focused on actually building a roadmap
with standards, because otherwise, we are just talking the talk
and we are not walking the walk. Again, I think the organic
example is an example that we should follow.
But thank you very much. I yield back.
Mr. Brown. And we do have that roadmap.
Mr. McGovern. Thank you.
The Chairman. Thank you very much, Mr. McGovern.
And now, I recognize for 5 minutes Congressman Crawford
from Arkansas.
Mr. Crawford. Thank you, Mr. Chairman. I appreciate it.
Mr. Duvall, thanks for being here today. I wanted to visit
with you a little bit about some of the things that you know
about our district. We are the largest agriculture district in
Arkansas, produce about \1/2\ of the U.S. rice crop in my
district. But, also a lot of production in other crops like
cotton, soybeans, a big producer.
A lot of the climate dialogue related to agriculture is
centered around carbon sequestration. I think it is important
to recognize that the diversity of agriculture demands that
there is not a one single solution approach that is appropriate
for every crop or every cropping system, or every region. But
there are some unique considerations to each of those areas and
systems.
Rice farmers are some of the most sustainability-minded
producers I think we have in the country, and they have
employed considerable techniques to increase efficiency, reduce
greenhouse gas emissions, and water use. And also, creating
excellent wetland habitat, which are very biodiverse with
numerous species of waterfowl, as you know. You have probably
even harvested some of those yourself.
My question to you, though, Mr. Duvall, is that one of the
great things about the farm bill conservation programs is that
they are flexible enough to help any farmer that wants to
address a natural resource concern that is important to their
farm. Whether it is a rice farmer that wants to work on water
management, or a rancher that wants to put up fencing, the
program allows farmers to decide. And I worry about a carbon
bank being accessible to everyone, and providing a level of
flexibility. Do you share that concern?
Mr. Duvall. I do share that concern, Congressman, and
farmers are concerned that we start a carbon bank, and then
some company in between the farmer and the people that are
buying the carbon credits makes all the money. What we need is
something that generates some additional income at the farm
level so that we can continue to do conservation practices. We
need partners, and of course, USDA is a great partner and has
been for years and years and years, and we look forward to not
just accelerating those programs to go from 30 to 40 percent of
cover crop to, hopefully 100 percent one day, and kind of
follow some of the principles that we heard Mr. Brown speak of.
But education is a key part, and he mentioned that, too.
But we need partners, and the carbon credit bank and moving in
that direction, we do have concerns in that area whether or not
it will be available to everyone.
Mr. Crawford. You mentioned partners, and I know you
mentioned in your testimony that you are working with Food and
Agriculture Climate Alliance, which has been very focused on
cover crops and soil health, as you also mentioned, related to
carbon sequestration. And as you know, and as I mentioned
before, rice producers hold water in their fields in the off
season that provides habitat for waterfowl. It also helps
decompose rice straw from the previous growing season. So, in
effect, ducks are our cover crop. It appears that the policies
that FACA has identified to sequester carbon might only work
for a couple of commodities. If the government provides an
incentive that is coupled to one or two commodities, then we
could see drastic shifts in plantings and markets. I am just
asking if you can look into that and work with them and with us
to make recommendations to make sure that we are able to avoid
that, and we find a solution to work for all commodities.
Mr. Duvall. I would agree with that, and we are very
concerned that a lot of the practices that farmers have been
doing for decades now have been sequestering carbon all that
time won't get recognized if we move forward, too. The rice
farmers, the pasture and cropland management we have already
done, forestry, all those farmers have been sequestering carbon
for years and years and years, and we need to recognize what
they have done in the past, too.
Mr. Crawford. I appreciate that. Thank you, Mr. Duvall, and
Mr. Chairman, I will yield back.
The Chairman. Excuse me. I wasn't on.
Now, I recognize, for 5 minutes, Ms. Adams of North
Carolina.
Ms. Adams. Thank you, Mr. Chairman, and to the Ranking
Member as well for hosting today's hearing, and thank you to
our witnesses for their testimony.
This is such an important topic. Climate change is a
crisis, and we must treat it like one. It is already impacting
our nation in deadly and destabilizing ways. And like this
pandemic, its impacts are being felt disproportionately by the
most vulnerable among us. Today's testimony has further
enforced that the climate crisis is also threatening our
farmers' ability to grow food in productive and environmentally
sustainable ways, which could have detrimental impacts all the
way up and down the food supply chain.
When talking about climate change and how it will impact
the agriculture sector, I also want to make sure that we are
strongly considering the role of our 1890 land-grant
institutions and the role they can play. These institutions,
such as North Carolina A&T State University, my alma mater,
have incredible expertise in conducting agriculture research
and providing extension services to farmers and ranchers,
particularly socially disadvantaged producers. I was proud that
our Committee included provisions within the American Rescue
Plan Act that will support these institutions, their students,
including resources for research and education and extension.
Professor Knox, I know that you are with the University of
Georgia, but I assume that you work with research and extension
professionals at other land-grant institutions. So, my question
is, can you provide more detail on how you collaborate with
other institutions, particularly with the professionals at 1890
institutions such as Fort Valley State University?
Ms. Knox. Yes, Congresswoman Adams, I am happy to answer
that. As you might not be too surprised to know, Fort Valley is
the group that I work with the most, since I do a lot of my
work with Georgia. We have had a number of research projects
that have specifically included folks from Fort Valley as part
of a consortium of researchers. Quite often those not only are
in Georgia, but they also include other researchers from
Florida and Alabama. And so, we draw not from just 1890s group,
but also from other universities. But they serve a very crucial
role in our research because they have an audience that we
really need to reach. We need to take our scientific knowledge
and make it useful to a variety of farmers, including a lot of
the Black farmers and minority farmers that have very unique
needs. A lot of them don't run really big farms. A lot of them
are growing specific kinds of crops, and we need to be aware of
those needs and really respond to them. And that is where the
1890s institutions really fall in, because they can help
translate the science that is being done by the researchers to
the farmers that are part of the community. And so, by doing
that, they serve really a critical role.
Ms. Adams. Great, thank you, and you've answered part of my
next question in terms of what role our institutions in
supporting research and education and extension related to
climate change, what is their role? And are there ways that we
can further empower 1890 land-grants to support this ongoing
work or to strengthen their collaboration with institutions
like yours to expand opportunities?
Ms. Knox. Yes, I think that there are always ways to
include, say, multi-university consortiums to do more research,
and I think there can be ways to say we really want to
encourage the 1890s land-grant institutions to participate in
that. And so, I know in the past some of the research groups I
have been on have specifically asked for those kind of
partnerships, and I would like to see that continue or maybe
even expand so that we can really use that expertise from the
1890s universities.
Ms. Adams. Great, thank you.
Mr. Brown, you mentioned carbon markets and some of your
priorities for the policy in your testimony. Currently, many
private carbon market offerings have minimum acreage
requirements, indicating that this solution will benefit large-
scale operations at the expense of small, diversified
operations, which I find concerning. The minimum acreage
requirements could have serious implications for consolidation
in the agriculture industry, making it even more difficult for
middle- and small-scale farms to survive.
How important is it that all farmers be able to participate
in carbon markets, and do you think that there are specific
steps that Congress and USDA can advance to ensure that farmers
of color and small, mid-size diversified and beginning farmers
can participate in and be rewarded for implementing climate
stewardship practices?
Mr. Brown. Thank you, Representative Adams, and yes, that
is certainly a major concern of mine as well.
It does not matter the size and scale of farms. They should
be rewarded based on their practices and their outcomes. Small
farms, in my opinion, have the ability to produce greater
outcomes. They should be rewarded accordingly. I would urge
that this Committee looks to ensure that these small farms have
the ability to be rewarded for what they are actually doing,
and that you make sure that any carbon market, the vast
majority of the income that can be had from selling carbon
credits goes back to the farmer themselves.
Ms. Adams. Thank you. I think I am out of time, so, Mr.
Chairman, I will yield back.
The Chairman. Thank you so much. That was very informative.
Thank you, Congresslady Adams.
And now, I will recognize, for 5 minutes, Congressman
DesJarlais of Tennessee.
Mr. DesJarlais. Thank you, Mr. Chairman.
The Chairman. Five minutes.
Mr. DesJarlais. I thank all of our witnesses for appearing
today. A special shoutout to Mr. Duvall from all the fine folks
at Tennessee Farm Bureau. As you know, we have the largest farm
bureau in the nation right in our district, and we are proud of
the working relationship we have. So, I would like to get a
question to you.
But my first question is going to go to Mr. Shellenberger.
It is timely because tomorrow we will be voting on H.R. 803,
Protecting American Wilderness Act, and western wildfires are
burning almost year-round now due to poor forest management. I
think we can prevent these disasters from breaking out in the
first place by doing a better job. We have over 80 million
acres of Forest Service land that is considered high risk for
severe fires, and we have overgrown forests that are in
desperate need of both management and hazardous fuel
reductions.
Mr. Shellenberger, how do you view the current management
of our nation's forests, and what should Forest Service and
other land managers be doing better to encourage healthy
forests?
Mr. Shellenberger. Well, thank you very much for asking the
question.
We saw a very dramatic instance last fall in California,
which is where I am based, where we saw a high intensity fire
that was burning through the crowns of forests that were badly
managed. When that fire arrived at a well-managed forest, the
fire dropped down to the ground and became a low intensity
fire. What that shows is that while climate change may be
influencing forest fires, it is neither a necessary nor
sufficient cause of high intensity fires, and the good news is
that with better forest management, whether it is through
selective harvesting, prescribed burns, or other methods that
we already know how to use, we can prevent those kinds of high
intensity fires from impacting our forests in the future.
So, thank you for the question. Absolutely there is more we
should be doing, and it needs to involve both the Federal
Government and state governments, given that a significant
amount of our forestlands are federally owned.
Mr. DesJarlais. Thank you. Contrary to popular belief, as a
doctor and as Republicans, we do believe in science and when
discussing climate policy, it is important to note that the
U.S. leads the world in reducing carbon emissions, and within
10 years, nearly 90 percent of all emissions will come from
outside the United States. But still in 2018, we on the
Agriculture Committee put together one of the greenest farm
bills ever, providing $6 billion a year to farmers, ranchers,
and forest owners to implement soil health practices such as
cover crops and no-till that can help draw down carbon and
store it in the soil. These changes came after hundreds of
hearings and listening sessions across the country where we
heard directly from farmers.
So, before I get to Mr. Duvall with a question, I hope, Mr.
Chairman, that you can commit to this Committee holding a
number of listening sessions with farmers and ranchers before
we pass any new climate legislation.
Mr. Duvall, can you talk about the importance of both
having stakeholder involvement in the creation of any new
programs, as well as any changes to current programs, and the
need to ensure that these are voluntary and incentive-based
programs for the farmers?
Mr. Duvall. Well, the voluntary market-based incentive
programs have been proven to work. Our farmers, if it is based
on sound science and they know that it will improve their
soils, improve their production to become more efficient, they
will grab a hold of those new projects and move forward.
Whether they are new or old ones, we need to make sure we
continue to support them, and you are exactly right. You all
supported them very well. We appreciate that. We just need to
do something--Mr. Brown mentioned we need to do more education
to the farmers of how they can use those programs. Our outreach
as good as it should be, and it needs to be available to all
sizes of farmers. We are all concerned that consolidation is
going on. That is not what a general public wants. We want to
be, there for the large farmer, but also make sure the small
and middle-sized farmer is able to succeed and participate in
all those programs.
To talk about having private investment, of course the
private companies out there, especially the food companies are
marketing their products in a certain environmentally sensitive
way, and if they are going to do that, they should be able to
put some of the money behind where their thoughts are and be
able to help support some of these expensive things like manure
digesters and other things that farmers are having to put on
their land to be able to help move forward in controlling our
climate.
Mr. DesJarlais. Thank you, Mr. Duvall.
As we all know and was mentioned, nobody cares more about
the land and the Earth than our farmers and our agriculture
community, so we are standing ready to make things as good as
we can.
So, thank you all, and I yield back.
The Chairman. Thank you very much, Congressman DesJarlais.
To answer your question, you can rest assured that this
Chairman of this Agriculture Committee will make sure that our
farmers are at the center of our movement out of whatever
legislation, whatever appropriations--that is the whole purpose
of this Committee is for us and agriculture to have the inside
pole position when it comes to climate change. My good friend,
Richard Petty, told me and gave me that great advice when I
asked him how he won so many races. He told me, ``Don't check
the ones I have won. Look at the number of inside pole
positions I have won.'' I didn't know what that meant at the
time, but later I did.
Mr. DesJarlais. Thank you, Mr. Chairman.
The Chairman. Then I looked back in the mirror and I can
see all the wrecks.
Our farmers will definitely--that is why we are having this
hearing, to make sure our farmers, our agriculture industry,
has the inside pole position on our whole response to climate
change.
Now, I would like to recognize the distinguished lady from
Virginia, my good friend, Ms. Spanberger.
Ms. Spanberger. Thank you.
The Chairman. Five minutes.
Ms. Spanberger. Thank you, Mr. Chairman, and thank you to
our witnesses. I came to Congress with a background in national
security, and I know that climate change presents a national
security threat. It also presents a threat to our health,
economy, and the future of our nation. But agriculture, the
work and purview of this Committee, can be and is part of the
solution in addressing climate change.
As you, sir, President Duvall, said in your testimony, U.S.
farmers and ranchers have long been at the forefront of climate
smart farming, and America's farmers and ranchers play a
leading role in promoting soil health, conserving water,
enhancing wildlife, efficiently using nutrients, and caring for
their animals. I am so glad to see our Committee address
climate change with the urgency that it requires, and I am glad
that we have brought farmers to the table, though virtually
only, today.
I am glad we brought farmers to the table in discussing the
role of agriculture in combating climate change. At times,
farmers have been left out of the national conversation on
climate change. When as we have heard today, farmers,
foresters, and ranchers can and in so many cases are a part of
the solution. We have heard from President Duvall and our
colleague, Mr. Costa, about how the practices they have
employed on their own farms have changed from the practices
their parents and grandparents used, and Mr. Brown has spoken
today and widely about his choice to employ new methods to make
his farm profitable and increase his soil carbon more than six-
fold.
Back home in Virginia, I have heard similar stories from
crop and livestock producers in my district about how farming
and conservation practices they employ are benefitting the
environment, building more sustainable operations, and
benefitting their bottom line. As Chair of the Conservation and
Forestry Subcommittee, I have listened to farmers, not just
back home in my district, but here in this room before our
Subcommittee. And as a result, I worked to introduce H.R. 7393,
Growing Climate Solutions Act last Congress with our colleague,
Representative Bacon of Nebraska, and this bill has been
endorsed by national farmer organizations, as well as large
environmental and conservation groups, while garnering the
support of corporations like McDonald's, Bayer, and Microsoft.
This legislation has built a broad coalition because it
empowers farmers to voluntarily employ or continue employing
climate-friendly conservation practices, and it would help
farmers unlock new revenue streams.
Over the next month, I will be introducing a series of
bills, including larger ones like (H.R. 2820) the Growing
Climate Solutions Act, or simple, straightforward ones like
H.R. 8057, Healthy Soil Resilient Farmers, and these bills
would ensure that farmers are front and center in the
conservation conversations that we are having, and that farmers
have the tools to participate and benefit from voluntary
programs as we all work together to tackle the climate crisis.
Now, I would like to direct my question to President Duvall
with the time remaining.
Just yesterday, Mr. Duvall, you published a column in which
you stressed the need to give farmers a voice at the table,
particularly when it comes to changes in conservation programs.
If the other Committee Members haven't read it, I recommend it
to everyone.
So, Mr. Duvall, could you expand a bit more for Committee
Members on how is it we can make sure that the voices of
farmers are heard when it comes to addressing climate change,
and how we can prevent some of the mistakes we may have made in
the past? Thank you.
Mr. Duvall. Well, Congresswoman, you have made the first
step today in asking me to come here and sit on this panel,
along with the other panelists that have done such a tremendous
job and have my respect.
We need to be at the table during the discussions so that
we can tell you how those policies that you are considering,
how it is going to affect us on our land? How is it going to
affect small, medium, and large farms? And as we do that, we
can tell you what will work and what will not work. You also
can help us make sure that the research dollars are there, find
the new technology that needs it. Let's make sure that we don't
tie our hands with the current technologies we have, because
those technologies have allowed us to make the progress that we
have made. And just like you said, as long as they are
voluntary, they are market-based, and they are incentive-based,
our farmers will latch on to it and do a good job with it.
So, I think you are making the right steps. Just please,
let us keep our seat at the table and we will make sure that
you have all the information from the countryside, from our
farmers, to make sure that you can make wise decisions that
make not only farming successful, but also makes our rural
communities resilient.
Ms. Spanberger. Thank you very much, President Duvall, and
to the other witnesses today, thank you so much for
participating. Thank you for bringing your knowledge, and thank
you for joining us. I hope that we will be able to welcome you
here in person at some point in the future.
Mr. Chairman, thank you for this hearing. I yield back.
The Chairman. Thank you, Ms. Spanberger. I have to remember
to put my light on there.
Now, I will recognize, for 5 minutes, Mrs. Hartzler from
Missouri. Oh, she's not on? Then we will go to Mrs. Hayes of
Connecticut. You are recognized for 5 minutes.
Mrs. Hayes. Thank you, Mr. Chairman, for holding this
hearing, and thank you to all the witnesses who are here today.
Can you hear me?
The Chairman. Go ahead, Mrs. Hayes. You are recognized for
5 minutes.
Mrs. Hayes. Okay. Climate change is an important threat to
Connecticut. From June 2016 through May 2017, Connecticut
experienced its longest drought since 2000. At one point, more
than 70 percent of the state was considered in extreme or
severe drought. Simultaneously, the average temperature in
Connecticut is continually rising. Since 1970, Connecticut has
warmed by 8, compared with the national average increase of
2.5 F. To compound these issues, more frequent extreme weather
is already costing Connecticut huge amounts of money. Between
2017 and 2019, Connecticut experienced two severe storms and
two winter storms. The damages led to losses of at least $1
billion. Small farmers in Connecticut are leading the charge in
sustainable agricultural practices, but we cannot leave the
health of the planet up to individual decisions.
As the Members of this Agriculture Committee, it is our
responsibility to ensure that the industry is providing clear
solutions to address climate issues.
My question today is for Mr. Brown. A report from the USDA
recognized increased food insecurity as a risk posed by climate
change. As a farmer who is practicing and teaching resiliency,
can you explain how climate change could impact levels of food
production, and ultimately increase global food insecurity if
we do not act?
Mr. Brown. Thank you.
The way for Congress and ranchers to not only mitigate
climate change by taking more carbon out of the atmosphere and
putting it into the soil is to make our soils more resilient.
In 2020, Burleigh County, North Dakota, where I ranch, was
the second driest year ever recorded. Yet, even though that
happened, we were still able to graze the same amount of
livestock. We were still able to raise profitable cash crops
because of the resiliency we had built into our soils, by
taking massive amounts of carbon out of the atmosphere and
putting it into our soils.
The other thing that many of us who are practicing
regenerative agriculture are doing, is that we are diversifying
our farms and ranches. So many of our farms and ranches today
are not diversified. They only grow one or two different cash
crops. They only grow or raise one species of livestock. We
need to diversify that, and by so doing, that is going to allow
society to have the food security we need.
Mrs. Hayes. Thank you. You are right. Clearly, it is
essential that we preserve the resiliency of our agriculture
sector if we have any hope of eliminating hunger in America,
which we have seen literally in the last year grow to be blown
to a much larger problem.
Mr. Duvall, we all know that heat stress will likely cause
the overhead costs of dairy farms to go up, while driving their
production down. Many small farmers in my district, dairy
farmers, already turn limited profits under this current
situation. Can you provide some steps that Congress and the
USDA can take to help small dairy farms as they prepare for
climate change?
Mr. Duvall. Well, of course, I think we have taken some
huge steps already through Congress to help in the farm bill
fix some of the problems we had around the risk management
tools that we had built in there for the dairy farmers, and
there has also been some private products that have been
offered to them.
But, we need to take a hard look at the Federal Milk
Marketing Order system. We need to make sure that our farmers
have an opportunity to speak to changes that are made in the
Federal Milk Marketing Order system, and that each one of them
have the opportunity to speak to that. So, we are, right now,
continuing to do a study of our own, and we will be glad to
share with you the results of that study as we finish it out on
how we move forward and make it more profitable.
We continue to see small dairies go out of business and
more consolidation in dairy getting bigger.
Now, this country--really, American agriculture was built
on the back of small dairies all over this country when we were
all real diversified, and it really is a shame to see these
small dairies not survive anymore. We have to find a way that
small, medium, and large dairies can survive in this
environment, and to help them be financially stable enough to
be able to take on the practices that, in some cases, are going
to cost a lot of money to help us end climate change.
Mrs. Hayes. Thank you, Mr. Duvall. I truly appreciate you
saying that, because in my district in my State of Connecticut,
small dairy farmers are really the backbone of our farming and
agricultural industry, so I really appreciate you saying that,
and for coming to this hearing because we cannot continue to
have these circular conversations debating if climate change is
real or if it is happening or what the impact is. We have
measurable data that tells us all this information, and now we
have a responsibility to act.
Thank you, Mr. Chairman. With that, I yield back.
The Chairman. Well, thank you, and also thank you, Mrs.
Hayes, for the excellent job you are doing as the Chairwoman of
our Subcommittee on Nutrition, Oversight, and Department
Operations.
And now, let me give an apology there. I got my paperwork
mixed up and recognized two Democrats. Now, thank you for
allowing me to represent and to recognize two Republicans.
Thank you for your understanding.
Next, we will have Mr. LaMalfa from California.
Mr. LaMalfa. Thank you.
The Chairman. Five minutes, sir.
Mr. LaMalfa. Thank you, sir.
Mr. Duvall, real quickly I wanted to touch on the concept
with the carbon banks and the USDA, maybe through CCC, being a
possible authority of establishing carbon banking. Has AFBF
looked into whether the USDA can do this on its own authority,
or would the Farm Bureau be joined with us in opposing any
attempt to have that just be done by Executive actions, as
opposed to running it through a Congressional process so this
can be vetted, and that there are not winners and losers on how
the carbon banks would work? Has Farm Bureau looked at that?
What do you believe the position should be on that?
Mr. Duvall. Yes, I haven't asked my staff if we were
looking into the legality of it. I will tell you that we are
concerned that if it is developed and financed through the CCC
that the levels of CCC borrowing authority is not nearly high
enough. We support raising that level to $68 billion. We think
because of the economy and the increases over the years that it
should be at that level instead of $30 billion. I have spoken
to Secretary Vilsack about that certain issue, and he committed
to me that he would not pay for it off the back of our title I
program or our conservation programs, so I was delighted to
hear that.
But, we are interested in seeing, this is the place.
Agriculture is the place. This is the Committee where we see
the most cooperation between both sides of the aisle. You all
always find a way to find ways to work together, and I hope
that in this environment we can continue to do that, and I
think I see that in the leadership of this Committee. And I
would love to see the conversation through this Committee
decide how that is going to be paid for and where it is going
to come from. If we are going to put in modern day agriculture,
we have to have modern day practices. It requires research
dollars. It requires extension and education. It requires
funding for new programs that we put out there if it has to do
with climate. The funding has to follow those programs so that
our farmers and ranchers can afford to do that.
Mr. LaMalfa. Yes, sir, I hear you.
Yes, I just don't want to see an authoritarian attitude
come out of this, because it looks just a little bit ominous.
What hasn't been talked about very much is an already difficult
situation with ag profitability, and where are they going to
find the profitability?
We have the concept of diversification. Well, certain
climates, certain soil types, certain water availabilities just
don't lend themselves to change crops, and I experienced that
in northern California. We have some of the best crops grown in
Central California if they have the water supply not taken from
them. That is the only place that many of these crops are grown
anywhere in the world--or in our country, at least. We would
have to import is part of the problem.
Mr. Shellenberger, I appreciated your testimony and your
way of talking about things in this conversation, as well as
recognizing farmers are doing a pretty good job in this country
in innovation and trying to keep up.
We are hearing a lot of talk about the crisis of climate
change, and what is your interpretation of where we are at,
especially with how what agriculture might be driving in or
helping with in this crisis as it keeps being presented ad
nauseum, in my view, around here. Please bring that in on
forestry, because my area is a part of the area that is burning
so much. I believe strongly that it is from an overload of fuel
in our western forests.
Mr. Shellenberger. Yes, thank you for the question.
I will make a couple of comments. I mean, I think the first
is that I think it is a mistake to use climate as the single
overriding measure of success with farming or anything else. I
mean, we see that carbon emissions have been coming down in the
same way that other air pollutants came down in the 1970s. It
is actually quite extraordinary progress in the United States
mostly due to the transition from coal to natural gas.
In the case of farming, increased efficiency and
productivity should be the goals, because those result in what
we call land sparing. It results in less land being used, less
fertilizer, less runoff, less air pollution, less land farmed.
I mean, there is less air pollution from farm machinery. So, I
think it is a mistake to organize strictly around carbon. I
think, in many ways, you want to organize more around land use
efficiency or input efficiency.
On the question of emergency crisis, those aren't words
that I think are very helpful. We saw some activists encourage
panic. That is not something we should ever encourage, since
panic means unthinking behavior. Climate change is a long-term
process. It is not something that you solve with one piece of
legislation or that one generation will solve. It is something
that we are going to be managing for a long time.
And so, when it comes to forests, I would love to see more
money spent on forest management. I think that is a much more
higher priority, since we just have a lot of fuel built up in
western forests that led to the severe fires that we saw last
fall.
Mr. LaMalfa. All right, I appreciate that. The crisis
really seems to be driven by a lack of forest management, and
the overload we have per acre of forest fuels, and we don't
seem to be able to get much cooperation. I appreciate that your
points on grazing could be part of that tool in your comments,
and grazing is always under attack in western states as part of
that tool. Great points as well on the more you cause some of
these effects, it takes more land to grow the same amount of
crops, and with that, more water that we are in short supply in
California as well.
So, Mr. Shellenberger, I would love to have you come up to
my ranch in northern California some time and talk about this
some more. Thank you.
Mr. Shellenberger. Thank you.
The Chairman. Thank you, and now I recognize Mr. Allen, for
5 minutes, from Georgia.
Mr. Allen. Thank you, Mr. Chairman, and I want to wish
everyone a good afternoon. Welcome to our panelists. I am just
delighted that we are having a hearing. For almost exactly a
year, this Committee has, for all intents and purposes, been
not operational. Since March 4, 2020, we have had one single
full Committee hearing, and in my opinion, this is inexcusable,
and I believe Chairman Scott and Ranking Member Thompson share
that opinion with me. I am looking forward to returning to
regular order quickly, and Chairman Scott, I appreciate again
your insistence on getting this ball rolling very quickly.
We have a lot of important business and oversight to attend
to. Particularly, we begin the preliminary first steps of
writing a new farm bill. It is hard to believe that that is
coming up so quickly.
Zippy, as you already pointed out, farmers are not the
problem when it comes to greenhouse emissions, with the ag
industry only producing about ten percent of U.S. greenhouse
gas emissions. We are kind of barking up the wrong tree with
this hearing. Farmers are the best environmentalists in the
world because they depend on the land for their livelihood.
In the Book of Genesis, we are told that God gave us
dominion over the Earth. All the challenges found in the ag
industry come right out of Genesis 3:18. God created man and
woman and he created them to tend the garden in which, again,
God created.
If we want zero net carbon emissions, there are a lot of
ways to do it. One is obviously plant three trillion trees
would be a start. But what the two sides of the aisle disagree
over is not really climate change. We all want to be good
stewards of the environment. What we disagree over is the power
that should be given to the government. Climate change at its
worst can be and is used by various actors as a Trojan horse by
which they gain the power to regulate and have total oversight
over every industry and citizen in this country. There is room
for both educated insight and common sense in this debate, but
right now I feel that we have too many absurd policy proposals
coming from the far-left alarmists.
One fact from the Earth Observatory at NASA on the actual
tilt to the Earth suggests that the debate on how much this has
caused is still ongoing. In fact, that piece of article says
that as the actual tilt increases, the seasonal contrast
increases so that winters are colder and summers are warmer in
both hemispheres. Today, the Earth's axis is tilted 23.5 from
the plane of its orbit around the sun. But, this tilt changes.
During a cycle that averages about 40,000 years--again, I think
I heard someone say this is a long-term issue, the tilt of the
axis varies between 22.1 and 24.5. Because this tilt changes,
the seasons as we know them can become exaggerated.
And Zippy, I will start off with you. I think you and I--of
course, I don't believe anyone has claimed that they are in
charge of that tilt. Zippy, I think you and I know who is in
charge of the tilt and who created it. But my first question to
you is what is the greatest environmental challenge that our
agriculture industry faces?
Mr. Duvall. What is the biggest environmental challenge?
Mr. Allen. Yes, sir.
Mr. Duvall. Well, I can tell you what the biggest challenge
is to agriculture. The biggest challenge to agriculture,
biggest limiting factor of agriculture is labor. But that
doesn't have anything to do with the climate.
Mr. Allen. Right.
Mr. Duvall. I think the biggest limiting factor is our
outreach and our communication. We need to make sure that we
continue to tell farmers, because we do not have every piece of
ground with cover crop on it. We do not use no-till on every
piece of ground. But we need to continue to talk about what
that does for us in the future, and we need to educate people
and move them toward that. But it takes partners to do that. It
takes money to do that, and of course, the programs that we
have had have helped us, but we need to continue to move
forward in that direction to put those practices on the ground.
Another one of the limiting factors is the amount of
research dollars that is being spent on these issues. I keep
hammering on that because it is important. Research has kept us
on the cutting edge of agriculture. A lot of times American
agriculture gets downplayed as the bad guy, where agriculture
in the rest of the world represents 25 to 35 percent of the
greenhouse gases, we only represent ten percent. We are the
leaders. Everyone should be following what we are doing in our
country, and we ought to be accelerating through research
monies and new projects to put on the ground and encouraging
people to do it. Partners, research, and moving forward.
Mr. Allen. Well, thanks Zippy, and I am out of time, and I
yield back, Mr. Chairman.
The Chairman. Thank you very much, Congressman Allen.
And now, I recognize the gentleman from Illinois, Mr. Rush,
for 5 minutes.
Mr. Rush. I want to thank you, Mr. Chairman. Mr. Chairman,
I was born on a farm, and as the son and grandson of two
Georgia farmers, I am very excited about being on the
Agriculture Committee, and I am excited about this hearing, and
I want to commend both you and the Ranking Member for
conducting this hearing.
My question to you, directed, rather, to Mr. Duvall.
Mr. Duvall, according to Feeding America, before the COVID-
19 pandemic, more than 35 million people struggled with hunger
in the U.S., including more than ten million children. The
coronavirus pandemic has made this situation worse, and we know
that climate change will only further exacerbate the problem.
Innovations in food production can enable growers to produce
higher yields with lower inputs and help crops sustain the
environmental stressors, and that will likely get worse during
the climate change. New technologies can also help address the
lack of fresh fruits and vegetables and food deserts, while
among other things, cutting down on food waste.
Mr. Duvall, how can we accelerate the development of new
technologies to prepare for a changing environment, the growing
problem of hunger? How can we assure that these technological
breakthroughs are widely shared to benefit socially
disadvantaged farmers and ranchers and urban communities who
have historically been unable to access nutritious offerings?
Mr. Duvall. Yes, sir, thank you for the question, and you
are exactly right. The technologies that we have had at our
fingertips have helped us improve our production by three-fold
in the last decade.
So, what can you do to help us? We need to streamline the
regulatory system. When these technologies come forward, let's
streamline the process to be able to get them approved and get
them out on the farms to help us do that. We can do things, put
crops in the ground that use less water. We can grow vegetables
that have more nutritional value. If all these technologies are
streamlined and instead of it taking 5 to 10 years, cut it back
to a year, year and a half and get it out on the farms so that
we can grow the crops, be more efficient, and keep the price
down, because the way we can produce in America, there is no
reason for anyone in America to be hungry. Farmers don't want
that. We want to do the best job we can. We want to keep the
cost of food reasonable so everybody can have access to it. And
we appreciate the work that Congress did with us and Feeding
America through USDA to deliver. When the market changed after
COVID hit, you helped us deliver food boxes to families and
helped our farmers change the way they marketed their food. So,
we are very appreciative of those programs. But streamlining
regulatory agencies to where we can get those products out to
the farm quicker.
Mr. Rush. Thank you, Mr. Duvall, for that fine answer.
Mr. Cantore, in your testimony you mentioned how, and I
quote, ``Children are being diagnosed with increasing
respiratory illnesses due to a more hostile atmosphere.'' We
know that Black and Brown children already tend to have a
higher risk of respiratory illnesses as a result of poor air
quality. As environmental conditions continue to change, what
impact do you anticipate that they will have on an already
vulnerable population?
Mr. Cantore. Thank you, Congressman Rush, for the question.
When you have these high air quality days, we have already
have tools out there at our disposal to keep people inside as
much as possible, but sometimes that isn't possible, and they
have to go outside. Things like asthma are certainly becoming
more prevalent with children and adults because there are so
many pollutants that are just trapped in the air, and the
longer we have these heatwaves--and they are popping up
everywhere. Nobody is unprivy to this. You are going to have
these pollutants just trapped and trapped in the air. Nothing
is there to mix them off.
In addition to what we are watching with weather, air
quality issues, even though it is not something we see coming
down at us, it is just as important to watch. So, these are
expected to increase in the future, sir.
Mr. Rush. I want to thank you, Mr. Chairman, and I yield
back the balance of my time.
The Chairman. Thank you, Mr. Rush.
And now, I recognize Mr. Kelly of Mississippi for 5
minutes.
Mr. Kelly. Thank you, Mr. Chairman. I ask for unanimous
consent that I get at least 25 minutes to ask my questions,
because there is so much in this, and I thank you for having
this important hearing. I am joking about the 25 minutes.
But one of the things I want to talk about is I want to
make sure that we are focusing on results, and not resources or
on one solution. Many times, we ignore results because once we
get invested in our solution or one way, we ignore new
technology or new solutions. And so, when we are talking about
zero emissions--I know Zippy Duvall talked about many farmers
now have zero emissions or net zero emissions, and I think that
is important. And going back to the cover crops and doing that
to enrich the soil, you have rice as Mr. Crawford brought up,
and I just got off a call with USA Rice, and talking about the
cover crops literally being ducks to flood those areas.
But in my area, we have many different types of crops, and
so I am not sure that they are the same cover and I want to
make sure we do the right research to get those. Whether that
be peanuts or cattle or sweet potatoes or poultry.
And so, Zippy, can you address any crops that may be a one
cover crop is not a--one solution is not--does not fit all, or
any specific crops which may have a different cover program to
make sure our soils are preserved? Can you address that, Mr.
Duvall?
Mr. Duvall. So, of course, I think all of us know trees are
the best way to sequester carbon. And then a diverse landscape
of different crops in different regions would be the next best
step. But there is tremendous work we do in the animal area.
There are feed additives, and I was asked earlier what can we
do to help it along? There are feed additives the FDA--they
consider those as drugs. They need to be considered as feed so
that we can get those additives approved and get them out on
the farm to lower the greenhouse gases that are coming from our
animals.
And, those are some of the suggestions I would make.
Mr. Kelly. Thank you very much, you know Mike McCormick at
Mississippi Farm Bureau and you, Mr. Duvall, have been such
great friends and great resources. I just hope before we do a
one size solution fits all, that we talk to our Farm Bureaus or
other organizations across our nation that represent all of our
farmers, not just certain areas, because regions are different.
The other thing, Mr. Duvall, how effective with getting
rural broadband to our farmers to have access and would that be
helpful to them being able to have the technology and the
information and education to farm better for our environment?
Mr. Duvall. I talked a little bit earlier about broadband
being part of that building on our infrastructure, and today,
broadband is not a luxury. It is a necessity. Whether it be
education, healthcare, and taking advantage of technologies
that are coming down the pipe that farmers can use to be more
efficient and more climate friendly. So, it is absolutely
necessary that we get those maps right, the Federal dollars
that you all are so kind to put out there to try to fill that
gap between urban and rural America, that those dollars go to
the correct places, because a lot of places those maps aren't
right. I struggle here with it in my house, and I am only 70
miles from Atlanta. So, we have to do this.
If you think about electrification back in the 1930s and
how important that was to all Americans, broadband is no
different. It has the same importance today that
electrification had back then, and we have to find a solution.
We found a solution to that one. We can find a solution to this
one.
Mr. Kelly. Thank you again, Mr. Duvall. I want to go back
to Ms. Adams' point. I have many 1890 universities that I
represent, HBCU, the many agricultural colleges, which includes
Mississippi State University, which is not an 1890s college,
but also an agriculture college. And I just think it is so
important that we use research dollars to allow these
universities to look at all these individual areas that I am
talking about in crops and specific regions, because nobody is
better situated to talk about specific regions.
I am running real close on time, and the final comment I
will make is, number one, invest in research and our 1890s
universities and other universities, agriculture universities,
and the second is we really need to get our State Department
engaged in foreign policy that deals with nations that are
either too poor or either ignore the environmental consequences
and climate consequences of their nation. We need to engage
them and make them part of our farm policy, whether it be
through trade or other initiatives with our foreign policy.
And with that, Mr. Chairman, I yield back.
The Chairman. Yes, thank you very much, Mr. Kelly, and
thank you for emphasizing our 1890s and the fine work you did
with me and the Committee. What a great bipartisan effort in
getting that $80 million down to those schools. I always lift
that up as one of our shining bipartisan moments.
And now, I would like to recognize the lady from Maine, Ms.
Pingree, for 5 minutes.
Ms. Pingree. Thank you very much, Mr. Chairman. Thank you
so much for hosting this hearing and making it our first
hearing. I think it really has been very interesting and
informational, and I really appreciate that we have a lot more
agreement than we often think that we do, and many of the
topics that we have brought have shown our similar thoughts.
I won't get a chance to ask everyone a question, but I do
want to thank all the presenters. You really have given us such
a great cross section, weather professionals to the importance
of the cooperative extension service, the farmers' perspective,
and Zippy, I really appreciate--I would like to have a meeting
with you. It was a long time ago because we can't have a
meeting anymore, but the work you have done with the Food and
Agriculture Climate Alliance is really a great way to bring all
the commodity groups and the farmers thinking together. I think
that has really advanced a lot of our thinking on this. So,
thank you so much on that.
I have worked on this topic for a long time. I care deeply
about it, and I encourage many of you to sign on to my piece of
legislation, (H.R. 2803) the Agriculture Resilience Act. I
think there are a lot of things we agree on that you all have
been talking about on both sides of the aisle: research, soil
health, viability for our farms, pasture-based livestock, food
loss and waste, which is a big topic that our cooperative
extension service mentioned. So, there really are a lot of ways
that are farmer-driven that we can work on this.
I want to try my first question on Mr. Brown. Thank you so
much for really representing the point of view of what it takes
for a farmer to make this transition. I want you to know, I am
longtime fan of yours here. I have your book. If you were in
the same room, I would ask you to sign it and I would give it
to one of my favorite farmers, because I really enjoyed reading
it. And I also want to thank you for giving a shoutout to H.R.
2859, the PRIME Act. We are not talking about that today, but
that really addresses the importance of having more
infrastructure available to farmers and farmers who want to
sell directly to consumers. There is a real dearth of
slaughtering capability in our country, particularly for small
and medium-sized farmers. So, I appreciate that you brought
that up.
You have gotten such a good explanation here to people
about the work that you have done. But I know for a lot of
farmers, it is very hard to make this transition. You have
invested a lot, farmers have in the way they do things. Maybe
it is generational. So, making this shift is a big leap, and I
know you do a lot with talking to farmers about how you made
the transition. What do you think we need to do to help support
farmers in those transitions through the programs that we have,
or other things that we could be doing more of?
Mr. Brown. Thank you. I would be happy to sign a copy of my
book for you anytime.
The number one thing that is needed--and Mr. Duvall touched
on this--is education. You don't know what you don't know. I
owe a debt of gratitude to NRCS. There are many good people who
work for that agency. They are moving in the right direction,
but they need to be given the opportunity to educate farmers
and ranchers. We need to really refocus conservation programs
to maximize the adoption of these regenerative principles.
Everyone here agrees that these principles work. Some say--
have said well, these principles--cover crops may not work in
my area. Well, they missed the principle of context. You have
to grow the species that work in your area. Farmers and
ranchers are not going to know that intuitively. Okay? We have
to use programs, use agencies like NRCS, the extension service,
to educate farmers and ranchers. And I think it is important to
note that by doing so, farmers and ranchers are able to
significantly decrease their inputs. I can't say that enough.
For instance, look at corn today. The average cost to produce a
bushel of corn is near $5, yet I know many regenerative farmers
who are doing it for less than $2 an acre because they are
educated and have the information that it takes in order to cut
those input costs.
So, thank you for the work you are doing. We certainly
appreciate it.
Ms. Pingree. Thank you. I don't have much time left, but
let me give it to Zippy if he wants to talk at all about the
food and agriculture work that you have been doing, and just
how that has brought so many different commodity groups and
farmers together to talk about these things?
Mr. Duvall. If you look at the Food and Ag Climate
Alliance, it is a historic alliance. Never before have these
organizations that think differently come together and agreed
on three principles and put forth 40 recommendations. We are
very proud of that work. We hope that people on the Hill as
yourself, Congresswoman, that you will use those
recommendations to help go forward and set policies.
But it was not an easy feat, and none of us knew that we
could make it happen. But when I sat down across the table from
environmental advocates, people's eyebrows kind of went up. But
we were able to do that because what we discovered is what we
all want is thriving communities, successful farming, providing
a great environment for our families, livestock, and the
wildlife. We all want the same thing. We just have different
ideas of how to get there. It is kind of like pitting
conventional farming against organic farming. There is room in
the marketplace for all of it, but we surely don't need to be
throwing each other under the bus. We need to be working
together to provide it for the people that want it, and provide
a good environment for us all to live in.
Ms. Pingree. Thank you. I have gone way over my time, but
thanks for the work you do for farmers. And to all the
witnesses, thanks so much.
Mr. Duvall. Thank you.
The Chairman. Thank you, Ms. Pingree, and now, I recognize
Mr. Bacon of Nebraska.
Mr. Bacon. Thank you, Mr. Chairman.
The Chairman. Five minutes.
Mr. Bacon. Thank you, Mr. Chairman, and it is such a joy to
be part of the Agriculture Committee.
Agriculture plays such an important role in Nebraska. It is
the primary industry. It is the backbone of our economy, and
even in Omaha, in the district I represent, agribusiness is the
core.
I just want to make a brief comment, and then I got two
questions. I just want to start off by saying conservative
climate solutions work. I mean, just look at the energy sector.
Over recent years, we have become the largest energy producer
in the world. We have become energy independent for the first
time since the 1950s. Just think about that, 70 years ago
roughly. We are exporting energy now. We are helping out our
allies in the Baltics gain energy independence from Russia. We
have done all of this while cutting emissions more than the
next 12 countries combined. I think that is an incredible
accomplishment. From 2005 to 2019, we reduced carbon emissions
by 33 percent, and we did this not by punishing people. We did
it by incentivizing behavior. We also did it by incentivizing
technology and innovation, and that is what we should continue
doing.
So, my first question goes to Mr. Duvall. We know farmers
are already making many positive changes, and we are already
seeing the results. So, my question is should we implement
policies for our farmers and ranchers to help them make more
money when they implement sustainable agriculture practices? In
other words, should we be focusing on incentives more so than
the punishments? Mr. Duvall?
Mr. Duvall. The heavy hand of any one network, even
sometimes when you think about our children, and when you make
it market-based, voluntary, incentive programs and prove to our
farmers that it has a science-base and it is going to provide
that kind of outcome, they are going to take advantage of that
program that you put out there. So, it is vitally important
that we make voluntary, market incentive-based programs as we
move forward. And we look forward to having that discussion
about what that looks like, and making sure that it fits all
size farmers. That is crucially important to us, because we
want to make sure--a lot of people look at American farmers and
say you represent the large farmers. We represent large,
medium, and small. We are always there to have their back, and
we look forward to working with you to find those solutions.
Mr. Bacon. Well, we look forward to working with you, too,
on this because this is the right way to go forward.
Conversely, I just want to get your input. What happens if
we put a carbon tax on our farmers, such as fuel and energy?
What kind of impact is that going to have on a farmer's top
line and margins?
Mr. Duvall. Inputs are one of the biggest expenses that we
have, and when you start taxing that, the profits in
agriculture are so razor-thin now, that is why people become
bigger, because the margins are thinner and thinner, and you
got to do more and more to be able to make a living out there.
So, if you put a carbon tax on it, it is just going to make it
more expensive, and it is going to be hard for people to make a
living.
I want to go back and touch on one thing. We want to be
energy independent. This country turned to American agriculture
to be part of that solution. We built a whole infrastructure
around renewable fuels, and we need not forget that farmers
answered that call, that infrastructure is valuable to our
rural communities, and it is valuable to our farmers to market
their grain. I think that is the important thing we need to
think about.
Mr. Bacon. Well, thank you, Mr. Duvall. I totally agree.
Mr. Shellenberger, how do we best balance implementing
climate solutions that don't raise the costs of food? For
example, if we do a lot of different measures, it could make
our beef, our pork, vegetables and fruits much more expensive,
and in the end, that affects the poorest amongst us. Those who
are most food-insecure will find themselves even more food-
insecure. So, how do we balance this while we are protecting
the most needy amongst us, in your view?
Mr. Shellenberger. Well, thank you for the question.
I think there is a real serious misunderstanding, because
there is this idea that if you make things more expensive, that
that is better for the natural environment, and that is just
not the historical pattern. We find that by making food
production and energy production more efficient, it also
becomes better for the environment. So, you just use less land
when farming, that is also part of reducing costs. Similarly,
you mentioned before that carbon emissions peaked and have been
declining since 2008. Very significantly, that occurred not by
making energy expensive, but by making energy more abundant and
cheaper, particularly natural gas with the Shale revolution.
So, I think that that should be the orientation. Anything that
seeks to make energy more expensive is obviously regressive. I
think Democrats and progressives and every other context would
oppose those things, just as we have tended to oppose taxes on
food. So, I think the orientation should be heavily towards
efficiency and productivity.
Mr. Bacon. Thank you.
Mr. Shellenberger. When we are looking at solutions, if
they start to make energy and food expensive, that would be a
red flag, both for equity reasons, but also for environmental
ones.
Mr. Bacon. Okay. Thank you very much, and Mr. Chairman, I
yield back.
The Chairman. Thank you. Thank you, Mr. Bacon, and now, I
recognize the gentlelady from New Hampshire, my good friend,
Ms. Kuster.
Ms. Kuster. Thank you, Mr. Chairman, and thank you for your
leadership and your decision to hold this landmark hearing.
I want to begin by noting the dedication and commitment of
farmers and foresters in New Hampshire to reducing emissions
and mitigating climate change on their land. they know, perhaps
better than any sector of our economy, how climate change
threatens their livelihoods, and we are seeing warning signs
already.
The USDA Hubbard Brook Experimental Forest in my district
has provided top notch analysis through their work studying New
Hampshire's climate for the past half century. They found our
average annual temperature has already risen a staggering 2.6.
Rainfall has increased, often in condensed periods of heavy
storms. Flooding has become more common, and as the Co-Chair of
the bipartisan Ski Task Force, I want to point out that we have
10 fewer days of snow on the ground. Climate change shortens
our maple sugaring season, complicates the growing season for
our farmers, and brings more invasive species to our forests,
and that is just the tip of the iceberg.
Our farmers and foresters have enough uncertainty to deal
with running their business. Climate change is exacerbating
those challenges.
So, one such effort is President Biden's 30 by 30
Initiative, conserving 30 percent of our land and water by the
year 2030. Our conservation heritage runs deep in the Granite
State, and more needs to be done to ensure that private farmers
and forestland will continue to serve this purpose as land
prices rise.
So, my first question is for Zippy Duvall. I know the Farm
Bureau is proud to note over 100 million acres of farmland are
now in conservation programs with the Natural Resources
Conservation Service, including 42 percent of agricultural land
in New Hampshire. Could you speak about the importance of
conservation from the Farm Bureau's perspective?
Mr. Duvall. Yes, ma'am, and thank you for the question. Of
course, those conservation programs putting land into
conservation with USDA has been vitally important. We put the
least valuable, less productive lands in that area. So, that is
extremely important. But we also have a huge moral
responsibility to recognize that as population grows, we have
to feed them. We have to feed them. So, we are interested in
continuing those programs that you speak of, but we also want
to see working land programs that helps us be more productive
there and do an even better job for the climate in those areas,
and that is going to require research and development dollars,
and extension and education, and broadband. It is just
crucially important. But those programs are very important, and
we are very proud to be part of that.
Ms. Kuster. Great, thank you. I 100% agree with you on the
broadband.
Ms. Knox, I appreciate hearing your initiatives. Your
counterparts at the cooperative extension at the University of
New Hampshire have been incredible partners to me and the
farmers and foresters in my district. You mentioned the need
for more research, as Zippy just did, to help foresters adapt
to new climate conditions, as well as best practices for making
working forests the most effective carbon sinks possible. From
your perspective, how can Congress be most helpful in fostering
this kind of research?
Ms. Knox. I think that USDA already has a number of
programs that are really geared towards improving research in
forestry. We certainly need to see more attention paid to that,
and we need to work with extension agents to identify not only
the research that's there, but also how to talk to landowners
about planting more land. You have to pick the right trees, you
have to pick the right location, and so, it is not just a
matter of the research on the trees themselves, but
communicating how the landowners can use that. The same thing
works with what Zippy said about technology. If you have
information but you don't have a way to get that to the
farmers, then you have really lost a critical step, and that is
really where extension falls in, because they talk between--
they are translators, essentially, between the scientists and
the farmers. And it works both ways, because the scientists
also need to hear from farmers, because they need to know what
is important to the farmers.
Ms. Kuster. And one last quick question. You talked about
the overuse of fertilizers contributing to carbon emissions.
Does your cooperative extension encourage farmers to adopt
strategies like planting trees and perennial grass to reduce
fertilizer usage and runoff?
Ms. Knox. They provide a number of different solutions. Of
course, in farming one solution does not fit everybody. But the
extension agents use a variety of techniques to talk about what
is the most responsible way to deal with the farm on a case-by-
case basis. So, they are really boots on the ground to look at
what is happening for individual farmers.
But yes, they do talk about that quite a bit.
Ms. Kuster. Great. Well, thank you so much for being with
us. My time is up, and I yield back.
The Chairman. Thank you, Ms. Kuster, and now, I recognize
for 5 minutes Mr. Johnson from South Dakota.
Mr. Johnson. Thank you, Mr. Chairman. I appreciate that.
I have a couple of things. I have enjoyed the comments a
number of my colleagues have made, like Mr. Bacon talking about
America reducing its carbon footprint by 33 percent from 2005
to 2019 he said. That is incredible progress. And then I liked
Mr. Scott, Mr. Crawford, and others talking about the role that
American ag producers have had in that environmental
stewardship, and I think it is fantastic. I am just thinking
about the impact that the farm bill, this incredible piece of
legislation that incentivizes and encourages good stewardship,
has had on clean water. You think about the impact, 19.3
million acres where we have had increased soil habitat, we have
had better soil health and habitat. There are a lot of success
stories to be told here in agriculture. And of course, I was
glad to hear Mr. Duvall talk about the role of technology. I
don't want to be a home state braggart, but of course, I do
want to recognize South Dakota State University and their first
in the nation 4 year degree in precision agriculture, because I
think that plays a role in good stewardship as well.
But Mr. Duvall, I want to dive in a little bit deeper into
a conversation that you noted that you and Secretary Vilsack
had. We have been talking about a carbon bank, and there are a
lot of questions I have about a carbon bank. You mentioned that
the Secretary committed that it would not, in any way, come at
the expense of title I programs. Can you tell us a little bit
more what that conversation was like?
Mr. Duvall. Well, I think it was just out of rumors that I
was hearing and it was referenced earlier--in an earlier
question. So, I just point blank asked the Secretary. He was
very--he didn't have to think about it at all. He said, ``I
understand how important the farm bill title I, all the
commodity programs are in conservation,'' and he says, ``I
don't have any interest in shorting them anything by using
monies from that area that would go into climate.'' Secretary
Vilsack, did a great job in the past, going to do a great job
in the future. We look forward to working with him, and I was
real satisfied with his answers.
Mr. Johnson. And so, did you get the sense--and I know you
are part of an alliance that has spoken in favor of a carbon
bank. I mean, is the CCC the mechanism that would be used,
either in your understanding or what Secretary Vilsack relayed,
to make these investments in a carbon bank?
Mr. Duvall. Our conversation did not go that far to talk
about whether or not the CCC was to be used to do that. I will
tell you the historic alliance that I spoke of, we are
interested in having that carbon bank and looking forward to
having that set up. And of course, the fear that we get from
the countryside of our farmers is what does that really look
like, and is it going to be valuable enough to actually make
that commitment? How many regulations are going to be around
it, and who is really going to make the money out of it? Is it
going to be an additional revenue stream to me on my farm to
help me be more assertive of doing more practices that are
climate friendly, or is someone in the middle going to make all
that money? Of course, we do trust USDA more than we would some
outside person handling it.
Mr. Johnson. Well, and I am glad you mentioned that kind
of--how does the money work thing, because hopefully you can
educate me and some others about this. I mean, there are high
transaction costs. I think a number of experts indicate that
that could be a real concern with something like a carbon bank,
and I think some estimates are that the highest recurring cost
associated with carbon credits would account for 50 percent of
the cost. Under that kind of analysis, only ten percent would
actually get to the producer, and that doesn't seem like a very
producer-focused mechanism in my mind. So, Mr. Duvall, give us
some sense of what your understanding of those costs would be?
Mr. Duvall. I think they still haven't been discovered yet,
and I think that the biggest fear farmers have is they want to
know before they buy into it or before they support that, and
before we support it, we got to know what that carbon bank
looks like, and we got to know what kind of return it is to our
farmers. Because ten percent--I am like you. I am not sure that
it is really a viable program. I don't think you will have a
lot of people participate.
Mr. Johnson. Sure. It looks like I am down to very little
time, but perhaps maybe the Chairman can give you an indulgence
of 1 more minute to answer my question. I mean, I do have
concerns about a carbon bank and what exactly the Federal
Government's role would be in it.
I got to be honest with you, Zippy. I have loved working
with you. Everybody in this Committee trusts you, and the Farm
Bureau. You are good people. So, give me some sense of what
analysis made you all comfortable getting on board with a
carbon bank? I have questions on impact on land prices, impacts
on market conditions, on private markets, on whether it should
be performance-based or outcome-based. I mean, what got you to
a point of comfort, because I am not there yet?
Mr. Duvall. Well, I will admit to you, I am not totally
comfortable yet, but I am ready to have the conversation what
that looks like and how we develop that market. And someone
really smarter than me is going to have to figure that out, and
I am sure there are smart people out there. So, I am just as
eager as you are to find out how this works, and what the--
because everybody wants to claim it as an alternative revenue
stream to farmers. I want to know what that revenue stream
looks like, and I want to know what procedure that carbon tax
or carbon market is going to return back to the farmer. There
may be a time in the future when we as an organization may not
support that, but we have to have a conversation about what
that looks like. And when we get those answers that you are
asking for, we will be glad to share them with you.
Mr. Johnson. Mr. Chairman, thank you for your indulgence. I
would yield back the negative time I have.
The Chairman. You are quite welcome, but I must admit and
assure you that Zippy is indeed a very smart man.
Thank you for that, and now Ms. Plaskett, you are now
recognized for 5 minutes.
Ms. Plaskett. Thank you so much. Thank you, Mr. Chairman.
As the Subcommittee Chair of the Biotechnology,
Horticulture, and Research Committee, I appreciate the
Committee's focus on climate change and its impact on our
farmers and ranchers. This is a topic I care deeply about, and
one that my constituents are already facing.
Early in the 116th Congress, the Biotechnology Subcommittee
held a hearing on examining ways for farmers to increase
resiliency and mitigate risks through research and extension. I
am so glad we are continuing that discussion here today.
I would like to direct my questions at Ms. Knox. In your
testimony, you touched on the frequency of extreme weather
events and how climate change can influence those events. This
is something that is painfully familiar to my constituents in
the U.S. Virgin Islands who experienced two major back-to-back
hurricanes in 2017, and have faced periods of drought in years
since. Specifically, your testimony touched on flash droughts
as an area of focus for your research. Can you elaborate more
on this phenomenon and why these droughts are so powerful to
farmers and ranchers?
Ms. Knox. Yes, ma'am, thank you for your question.
Flash droughts is an area of huge concern right now in
agriculture. Flash drought, if you don't know, is a drought
that comes on very rapidly, and so because it is coming on
rapidly, often with either high temperatures or a complete lack
of rainfall, or maybe some of both, really accelerates stress
on plants. And of course, plants need to have regular amounts
of rainfall or irrigation water to survive. And so, when we
have flash droughts, the plants can go from healthy and
thriving to really stressed and sick plants in a very short
time, sometimes even as much as a week. And so, our ability to
identify those flash droughts is, of course, important because
then it will tell the farmers they need to do something about
it. But we also need to be able to plan for what can you do to
help keep your plants alive during these times of flash
drought. And so, you can use irrigation, you can grow different
types of crops, you can do cover crops which keep more soil
moisture available. But all of those are things that need to be
looked at.
Flash droughts, one of the projects we are working on right
now looks at soil moisture and measuring soil moisture, because
that is an important piece of information that farmers need to
have, and yet, there is not a lot of really inexpensive pieces
of equipment that people can use to do that. So, some of the
projects I am working on right now are to identify some of
these less expensive ways to monitor soil moisture, and provide
that information to the farmers in a way that they can use it
to put on just the right amount of water. They don't need to
overwater, but they need to put on enough water to keep the
plants alive.
Ms. Plaskett. Thank you.
What is the role of cooperative extension in helping our
farmers and ranchers become more resilient, particularly for
those who are small scale and limited resource producers?
Ms. Knox. I think cooperative extension plays a really
critical role because there is a lot of research that is out
there, but it isn't necessarily getting to those small
producers in a form that is useful to them. So, cooperative
extension really serves as a way to translate some of that
research into useful information. And I am a pragmatist, so I
want to make sure that whatever information is provided is
useful and is in the right format for those producers.
And so, every situation is different. You have to go out in
the fields, perhaps. A lot of extension agents spend
significant amounts of time walking the fields with their
farmers, and so they really know the needs of those particular
farmers. And it could be big farmers or small farmers. But they
need to be able to talk in such a way that the information that
is provided by the scientists is useful, and they need to
listen to the farmers and tell the scientists what they should
be working on, because the scientists can't really work in a
vacuum either.
Ms. Plaskett. Okay, thank you.
In the short time that I have left, can you say what
additional research is needed to better understand how climate
change will impact farmers and ranchers, and how USDA can help
close those knowledge gaps?
And after your answer, I yield back. Thank you, Mr.
Chairman.
Ms. Knox. Thank you.
Some of the research that we don't really know very much
about, we know that climate change is going to impact
temperatures. We don't know really how well it is going to
impact things like solar radiation or moisture balance in the
soils, because those are secondary things, and they depend on a
lot of other things that are not as easy to resolve, say, in
climate models. For example, the cloud cover, which obviously
controls the amount of sunlight. But sunlight is important to
the growth of many crops, and if you have cloudy conditions, if
you have a lot of rain or just cloudy conditions, then it is
very difficult to plan how fast the crops are going to grow.
And so, looking at some of the secondary variables that are
really important for agriculture, which include things like
soil temperature and humidity, and things like degree days and
how fast they accumulate, cloudy conditions, are all important.
Ms. Plaskett. Thank you very much. I yield back, Mr.
Chairman. Thank you for the time.
The Chairman. Of course. Thank you. Thank you very much.
Now, we have had a call of votes. This is an important
hearing. We have a wonderful panel, and we have Members that
want to make sure they are recognized for questions. So, my
excellent staff and I have worked out a procedure that we are
going to do where we will keep our hearing going as some of our
Members go. And as you go, remember, please, as soon as you
come back, to make sure you contact the staff and let us know
that you are back in position.
Now, it has just been called, and let's see. Where is my--I
had a list of--no, the--oh, here it is. Okay. These are the
next five Democrats and Republicans who will be recognized, and
the reason I am calling their names is hopefully they will be
here and vote. Others who are further down can leave and then
come back quickly.
So, Mr. Baird, you are next. That is followed by Mrs.
Bustos, and then Mr. Hagedorn, and then Mr. Carbajal, and then
Ms. Craig and Mr. Cloud. That is six--one, two, three, four,
five, six people at 5 minutes gives us a good half hour here
now, and these six can go and hopefully some of you all who are
leaving now whose names have not been called, you can leave and
hurry back within the next 30 or 40 minutes, and we can keep it
going. I think that is our strategy.
Okay. Now, I assure you that everyone will be recognized.
This is an extraordinarily important hearing, and we can work
this out. So, those of you whose names I haven't called, please
feel free to go. We are coordinating with the floor and they
will allow you to vote as soon as you get there, so you can
return. Thank you. Is that right? I see Anne here. Is--did I do
all right, Anne? Okay. Anne says I did.
Now, we will recognize Mr. Baird.
Mr. Baird. Thank you, Mr. Chairman, and I really appreciate
you and the Ranking Member having this very important hearing.
It really gives a platform to highlight agriculture and its
importance to providing practical solutions to this climate
change. And so, it is extremely relevant, and I am so pleased
to be a part of it.
My first comment really goes to Mr. Brown, and it is just a
comment, because I think it leads to my question to Mr. Duvall
next. But, it is exciting to see the soil samples that you
held, Mr. Brown, and the changes you made in that 20 year
period, and the relevance of capturing carbon in the soil. The
black color and the interaction of that carbon, and its
importance in helping improve productivity. So, anybody that
knows anything about soil, those two soil samples you held up
were just very informative. And so, it looks to me like with
the one slide you had, you were able to move in a 20 year
period, 1993 to 2013, from one percent or less than one percent
carbon in the soil, and went to a level of seven percent. So,
it is exciting to see that we have and farmers and ranchers
have already been incorporating things that help carbon
capture, and I think that is important.
So, now I need to get on to my question, and that really--
you alluded to it before, Mr. Duvall, but it has to do with the
regulatory concerns for livestock feed. The development--and
livestock has been a part of my life, really all my life. I
grew up in west central Indiana. I went to Perdue, so animals
and a Ph.D. in monogastric nutrition all contributed to my
concern about livestock. And so, you mentioned greenhouse gases
and the emissions associated with livestock, and so on.
Feed additives have been shown to reduce methane levels
produced by ruminants by as much as 30 percent. The addition of
enzymes to chicken feed can also improve protein digestibility,
which helps reduce nitrogen emissions from the manure.
Probiotics help animal feed and improve the gut health of the
animal. Not only do these additives increase the nutritional
value of the feed and lower the cost of production for the
farmers, but it ends up being a win/win situation because we
can reduce greenhouse gas emissions.
As you mentioned earlier, many of these innovative products
lack a suitable regulatory product category, and they end up
being involved as animal drugs rather than being a feed
additive. And so, I am pleased to see that the Food and
Agriculture Climate Alliance, FACA, that the Farm Bureau has
founded identified the need to expedite and reduce this
regulatory burden in regard to FDA feed additive approvals.
So, having said that, I would like to give you the
opportunity to comment on what you think we need to do to
streamline those FDA approval processes, and if there are any
incentives or rewards that we can use to help producers utilize
this kind of technology? Mr. Duvall?
Mr. Duvall. Congressman, I am a farmer and I am an animal
agriculture farmer out there for 30 years, and also worked for
my dad as a child for 20 other years before that. And now I
have beef cattle, and this is my 34th year growing chickens. I
will tell you that that environment is the first area that you
can improve your farm more than anything. Animals eat grass,
and grass sequesters carbon. So, it all works together and kind
of plays off what Mr. Brown was saying.
The regulatory system, and I will admit to you, I don't
know that I can give you the recommendations, but I will sure
seek my staff on it to give you some recommendations about that
in writing afterwards. But we know that it is very cumbersome.
It takes too long. These companies go out and develop these
additives that are food additives that helps us do this, and
they have put tremendous dollars into creating them, and then
they have to sit on the shelf at FDA and the things that we use
to grow plants, to head off pests and disease, they sit on the
shelf and they are just grilled to death for years and years
and years. And by the time they get to the field, a new one is
already on the shelf waiting to be approved the next time. We
shouldn't be that way. We have people to feed. We have
Americans that are hungry. We need to keep food affordable. We
need to be as efficient as we can, and the only way we can do
that is to streamline that system so that we can have those
innovations and research reach the farm quicker.
Mr. Baird. Absolutely. Thank you for your comments.
Any other witness would care to comment about that?
The Chairman. Mr. Baird, your time is up.
Now we will recognize Mrs. Bustos for 5 minutes.
Mrs. Bustos. Thank you, Mr. Chairman.
My question is for Mr. Brown. In your testimony, you
mentioned the benefits of sustainable practices and how they
can help sequester carbon, increase water capacity and
absorption, build resilience, and mitigate risk. These themes
are consistent with the goals of something that I wrote out of
my office called the Rural Green Partnership.\5\ That is a
framework of policies and principles that are geared toward
getting rural America involved in the climate conversation, and
making sure that we play a part in spurring economic growth in
our part of the country.
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\5\ Editor's note: the statement referred to is located on p. 383
and is available at https://bustos.house.gov/bustos-announces-rural-
green-partnership-to-combat-climate-change-and-spur-economic-growth/.
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So, as a Member of Congress who represents a district where
ag is our main economic driver, and as Chair of one of the
Subcommittees of this Committee, General Farm Commodities and
Risk Management, these are all issues that are top-of-mind for
me, because they are top-of-mind for the growers and producers
that I am lucky enough to represent in northwestern and central
Illinois.
So, over the past few weeks, we have been hosting a series
of roundtables, and in every single one of them, our growers
and our producers are talking about how they are engaging in
sustainable best practice like cover cropping, no-till farming.
But they don't feel that the Federal incentives match up with
the work that they are putting in on the farm.
So, Mr. Brown, and then--I would like you to go first, and
then maybe Mr. Duvall, if you have something to add. Here is my
question for the two of you. Where do you see potential for
increased Federal investment and incentives to help more
farmers adopt these practices while also rewarding those who
have already been active in this space? That is also something
that we have gotten some questions on.
Again, Mr. Brown, if you can go first, please?
Mr. Brown. Thank you. Thank you for the work you are doing.
Where it begins is, as I said before, in education. You
don't know what you don't know. We need to educate farmers and
ranchers as to these principles. We need to show them that by
applying these principles, they can significantly not only
mitigate climate change, but they can significantly lower their
input costs and increase their profitability.
We seem to get hung up here on production and yield in
pounds, and yes, we need to feed America, but what most don't
realize is that production increases as we use these
regenerative practices. Also, not only does production
increase, but the nutrient density of our foods increases
significantly. And I think that has been totally overlooked. We
want to help the underserved? Let's increase the nutrient
density. The only way we can increase nutrient density of foods
is through healthy soils on land-based produced foods.
Take a look at the work that Dr. Stephan van Vliet is doing
at Duke University Medical Center using a mass spectrometer to
measure over 2,500 different phytonutrient compounds in food.
He is doing work currently that is showing a significant
difference between food grown in the current production model
and food grown in the regenerative model. Farmers and ranchers
need to learn about this, and then they need to be rewarded
with an outcome-based for the principles that they produce--for
the principles that they enact.
We cannot keep going down this model where the only
incentive is based on yield in pounds. It does no good if we
are feeding our society cardboard. Take a look at the facts. We
are spending twice as much on healthcare as we are on food.
Now, I am all in favor of lowering the cost of food from the
standpoint that--but we have to do it in a way that brings
profitability back to the farm and ranch. I agree totally with
Mr. Duvall on that. We have to increase profitability to the
farms and ranches. He talked about margins being razor thin.
Well, I am sorry. One of the reasons I don't accept any
government programs or subsidies is because I can't--I have
decent margins because I have been able to lower my input costs
due to the fact that I have enacted these principles.
It all goes back to education. Thank you for your question.
Please, this Committee has the ability to make sure that we
educate through NRCS, through extension, and through other
means. Thank you.
Mrs. Bustos. Very good. Mr. Duvall, I am going to pass on
you answering any more, because I have 8 seconds left.
And with that, Mr. Chairman, I yield back. Thank you so
much. Thank you, Mr. Brown.
Ms. Adams [presiding.] And thank you. I want to recognize
now the gentleman from Minnesota, Mr. Hagedorn.
Mr. Hagedorn. Thank you, Madam Chair. I appreciate it. It
is good to be at the hearing today, and Mr. Shellenberger, I
appreciated your presentation and the way it demonstrated that
farmers in America are already doing things to be sustainable,
and to manage their land properly. And in many instances, of
course, we lead the world in all that.
But I find it really difficult to have a hearing about the
effects of so-called manmade climate change and what we need to
do about it with agriculture, and not address the proposals
that are out there that would change the energy sector in this
country, and what that would do to sustainability of our
farmers from generation to generation, and the profitability of
our farmers and keeping the price of food affordable for the
American people.
Now, President Duvall, let me ask you. I am going to list a
few programs here, and I would like you to let me know if the
Farm Bureau affirmatively supports any of these energy policies
that are proposed by the Democratic party at this time in one
way or another, whether it is the President or Congress.
So, obviously these are all like the Green New Deal. First
of all, the cancellation of the Keystone Pipeline. I will read
these out, and you just let me know if you support any of them.
Cancellation of the Keystone Pipeline. Imposing a carbon
tax. Obama's Clean Power Plan. A ban on fracking. Rejoining the
Paris Accord. Imposing livestock ban. Enacting a cap and trade
system or mandating the phaseout of the combustion engine at a
certain point, and the end of gasoline and ethanol use as we
know it today. Does the Farm Bureau support any of that?
Mr. Duvall. No, sir, we do not support any of those.
Mr. Hagedorn. And that is my point. If you are worried
about farmers and sustainability, these are the types of
policies that are going to dramatically drive up the cost of
energy for agriculture, agribusinesses and make it darn near
impossible for most of our providers to stay in business, and
to produce affordable food and an array of products for our
people. I mean, depending on the commodity prices and the cost
of fuel, 30 to 40 percent of the cost of producing a bushel of
corn can be energy.
So, all these policies are very highly inflationary, and
they are going to hurt our farmers.
Now, Mr. Shellenberger, in a recent 60 Minutes
interview,\6\ billionaire Bill Gates suggested that established
nations like the United States should transition to eating
fake, synthetic plant-based beef. And he even went on to say
that government should force regulation of fake meat to force
consumers to comply if they didn't like the taste, effectively.
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\6\ Editor's note: the interview referred to, Bill Gates: How the
world can avoid a climate disaster, is retained in Committee file and
is available at https://www.cbsnews.com/news/bill-gates-climate-change-
disaster-60-minutes-2021-02-14/.
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Now, based upon your presentation, does Bill Gates or this
type of recommendation, is that, based upon any accurate
understanding of the U.S. beef industry?
Mr. Shellenberger. Well, I can't be--I didn't see the 60
Minutes interview, so I can't specifically comment on it, other
than to just observe that it would be impossible for any
government to mandate particular diets.
Just about four percent of the population is vegetarian,
and most vegetarians eat some form of meat during the year. My
view is that we should continue to innovate for alternatives to
meat production, but certainly not mandate it. And as I
mentioned, the meat industry has done a very good job at
reducing their impact on land, particularly the transition from
pasture beef towards more conventional concentrated beef
production has been astounding.
So, yes, I mean, I support the innovation. I don't think we
are going to mandate that.
Mr. Hagedorn. Well, let me reclaim my time.
There is plenty of opportunity for the Federal Government
and Democrats in Congress to mandate. They are going to mandate
all these things that have to do with energy and what kind of
cars we can drive, or what kind of energy is produced. There is
no reason to think that they couldn't come forward and try to
mandate that we could no longer have livestock production in
our country the way we have it, and that we would need to move
towards plant-based diets.
So, I would say that the biggest threat to production
agriculture's future in the United States isn't so-called
manmade climate change. The biggest threat to production
agriculture's future in the United States is the Green New Deal
and these extreme climate change agenda policies of the
Majority party. And raising the cost of energy is something
that should be addressed by this Committee. We should have a
hearing on it because when you dramatically raise the cost of
energy, you are going to undercut the profitability of farmers
and you are going to take generational farmers and run them out
of business, and we are going to disrupt this incredible system
of agriculture that we have in our country.
With that, I yield back.
Ms. Adams. Thank you very much.
I want to recognize the gentleman from California, Mr.
Carbajal. You are recognized for 5 minutes.
Mr. Carbajal. Thank you. Thank you very much, Madam Chair.
I represent one of the most beautiful places on Earth, the
Central Coast of California. It features some of the most
diverse habitats in North America, and it is also home to a
robust and diverse range of agriculture products--or
production, I should say.
Over the past decade, California has become more prone to
weather extremes, and the Central Coast is no exception. Our
community has felt the climate change crisis in a multitude of
ways: more severe droughts, increasing frequency of heatwaves,
and record setting wildfires.
Producers in my district are utilizing funding from
Environmental Quality Incentives Program, EQIP, and the
Conservation Stewardship Program, CSP. While I am glad to see
farm operations in my district using important conservation
practices, I have also heard that access to these programs can
be improved.
Mr. Duvall, can you discuss the role of USDA conservation
programs in addressing climate change, and helping farmers
build resiliency? Can you speak to the demand for USDA's
conservation programs?
Mr. Duvall. Well, thank you, sir, for the question. I will
tell you that those conservation programs are widely used, and
I will tell you there are a lot more people that apply for them
than actually receive them, because they run out of funds.
There are not enough funds there to complete every project that
a farmer will put forward. So, I think a lot of it is limited
by the amount of funds that the Secretary has put in those
areas. But they are widely used and they are widely popular.
Mr. Carbajal. Thank you.
Agriculture employers are constantly challenged by
unpredictable weather, and they now have an ever-increasing
need to protect farmworkers from extreme weather concerns.
Ms. Knox and Mr. Cantore, can you talk to me about the
effects climate change has on farmworkers? What health risks
may they experience while working in extreme weather
conditions, including poor air quality due to smoke?
Ms. Knox. Well, let me start off by saying that there are
several different ways that farmworkers are affected by it. One
is by the likelihood of increased heat stress. Farmers working
outside, especially as temperatures go up, are more prone to
have heat-related diseases, and so people who hired them have
to make sure that they are providing appropriate health-related
cooling areas or whatever, or modifying hours to make sure that
the heat stress is not building up on them.
But as you point out, the air quality, especially in the
western United States, is a very huge concern for people that
are working outside. We have seen that with the vineyards and
some of the vineyards that have really been hit by the fires
out West, and how that smoke has really carried a long ways.
But I will stop so I can let Mr. Cantore answer that as
well.
Mr. Cantore. I mean, when you take a look at the fire
situation just last year, over 4 million acres burned. The
pictures that we saw out of San Francisco looked like some kind
of movie set, but that was real, and those people had to
breathe that air for days, workers alike.
So, if we get into a situation where these droughts worsen,
and we get into these mega droughts that go year after year
after year, and you increase 4 million acres two to six times,
it is not only San Francisco and the vineyards that are going
to be dealing with poor air quality. It could be the whole
state. As a matter of fact, it is not just the whole state. A
lot of that air, that poor air quality is carried east into
other states, across the Rockies, to the Plains, into the
Southeast. Heck, down here in Atlanta. You probably have seen
the smoky skies, and it is not from the African dust but the
smoke from the wildfires in the West. So, everybody suffers
from this, and that is, to me, one of the worst things in terms
of air quality.
Mr. Carbajal. Thank you both for your answers.
I happen to have agriculture as the number one industry in
my district, and at the same time, I come from a family of
farmworkers. So, I happen to see it from both perspectives, and
I really do appreciate your answers.
With that, I yield back, Madam Chair.
Ms. Adams. Thank you. I want to recognize the gentleman
from Texas, Mr. Cloud. You have 5 minutes, sir.
Mr. Cloud. Thank you very much. I appreciate the
opportunity to have this conversation. It is extremely
important that we do have a discussion on how to steward our
nation's resources.
Mr. Brown, I have to say, not to invite myself over, but I
do hope that one day I can visit what you are doing there. It
seems like you are doing some great work. You mentioned that
your regenerative farming practices are able to produce more
per acre while also increasing profit and being more effective.
Is that what I understood?
Mr. Brown. That is correct, and we are doing it in Texas
also.
Mr. Cloud. Okay. Well, that is even closer, so maybe I will
have to stop by.
So, there is a built-in incentive already to move this way,
am I correct?
Mr. Brown. That is correct. I didn't get any incentives. I
did it all on my own. I did, though, early on take advantage of
EQIP and CSP contracts through NRCS. That was an important part
of me starting down this path, but as soon as I was financially
able to do it on my own, I would rather see that money go for
other underserved or people who are starting out.
Mr. Cloud. So, there is some initial cost getting started,
and once you got started, it is self-sustaining, I guess is
what you are saying, right?
Mr. Brown. That is correct.
Mr. Cloud. And you were able--I mean, this was just
motivation in your heart to do, right? This was voluntary?
Mr. Brown. Okay. No, my story was I started no-tilling
actually in 1993. That I started on my own because it made good
sense in my semi-brittle environment. Then what happened, the
years 1995 through 1998, I lost 3 years of crops to hail, and 1
more year to drought. Financially I was going broke, and I had
to figure a way how can I make my soils, my resource productive
without all the expensive inputs? And that sent me on an
education and learning process, at times learning from land-
grant institutions, at times learning from other producers,
learning from ARS. ARS was very important in my learning. And I
picked up bits and pieces and learned these principles, and
learned that they can truly work anywhere in the world where
there is land-based agriculture.
Mr. Cloud. Thank you very much.
I would like to say that the road to $30 trillion of debt
is paved with good intentions. Of course, we do have a role to
play here in the Federal Government, and there are important
investments we need to make.
Mr. Duvall, I am not sure you are the best one to answer
this. Do you have an estimate on how much it would cost to
establish and operate a carbon bank?
Mr. Duvall. No, sir, I am not qualified to answer that
question.
Mr. Cloud. Or anyone else? I don't know if anyone else
does. No? Okay.
I mean, currently we have some volunteer carbon banks in
place, and right now, the highest cost, my understanding, in
operating them is the cost of verification. Basically, a severe
bureaucratic burden. Only ten percent of it goes to the farmer,
and so, in pragmatic terms, I don't know of many programs where
the government has done things more efficiently, so I do have
some concerns in that. Because pragmatically, and this would be
typical of many Federal Government programs, is basically we
would be taking $10 of investment out of another industry that
also needs to make gains, transferring it through the Federal
Government to the ag industry. Eight dollars of that would be
lost in the bureaucracy somewhere, and only $1 would go to the
farmer. And while that would be some small benefit to the
farmer, a lot of the overall cost of what we could accomplish
basically would be lost in a Federal bureaucracy.
So, it seems to me that we have to be very careful about
overreaching here. I think, as has been stated, communication,
education on the best practice is extremely important. And I
would say not mandating the best practices, I wonder if Mr.
Brown would have been able to make the advancements he made if
we locked in the best practices of 20 years ago as a mandate,
would allow that to happen as an environment that allows for
innovation. And to that point, I would like to just say, Mr.
Shellenberger, I really appreciated your balanced testimony and
information-based evaluation of the state we are in as a
nation. Too often we see the road left to the advancements that
we still need to make, and sometimes those get demonized and we
don't take the time to remember how much progress we have made.
Could you just summarize and recap the United States, among
other nations, the innovations we have made toward effective
and sustainable farming?
Mr. Shellenberger. Yes, I mean, gosh. There are so many of
them, right? We are a huge innovator. I mean, all of the
technologies in your iPhone, in those GPS-driven tractors----
Ms. Adams. The gentleman's time is up. The gentleman's time
is up. Thank you.
I would like to recognize the gentleman from California.
Mr. Harder, you are recognized for 5 minutes.
Mr. Harder. Wonderful. Thank you so much. Thank you so much
to Chairman Scott and Chair Adams, and thank you for hosting
this hearing on this important topic. Thank you so much to the
witnesses for contributing your testimonies.
I think that in our valley, we have really seen--the
California Central Valley, we see farmers on the forefront of
climate change, especially in our district. We have seen
farmers face wildfires, face droughts, face floods, and I know
how much the changing climate can impact them. It is not just
affecting some polar bear in the Arctic somewhere else. It is
affecting the everyday lives of every farmer and grower
throughout our community. And I think folks really want to be
part of the solution. I took a lot of time with our Farm
Bureau, discussing updating farm equipment, by using low dust
harvesters on almond orchards. And frankly, there is a lot of
interest. But folks on the ground often express some of the
financial challenges in purchasing or updating their equipment
or technology, or needing staffing assistance to keep growing
their climate updates. One of my constituents shared that for
her almond orchard, it would cost about $200,000 for a low-dust
harvester, and an additional $70,000 for a low emission
tractor. And so, with my work in business and startups, that
was my background before coming to Congress, I understand how
these decisions are made. And I understand that they really
need to make financial sense if ag operators are going to move
them forward.
So, we have worked a lot with ag groups and environmental
groups to introduce H.R. 7482, the Future of Agricultural
Resiliency And Modernization Act, which I think is one of the
only bills that is actually endorsed by our local Farm Bureaus,
as well as by a number of environmental groups all around
ensuring that we can make sure that we are moving towards more
agricultural resilient practices. It basically creates a
Federal partnership for farmers to access financing, which
would provide grants that support climate-friendly projects. It
also creates a pilot program for pyrolysis, which essentially
helps convert tree nut byproducts into climate-friendly
biocarbon, a really important effort especially in California's
Central Valley.
So, my question is actually for you, Mr. Duvall. As the
President of the American Farm Bureau with such a wide-ranging
network of members across our district, what have you heard are
the financial needs of farmers in this space, and how can
Congress or the Federal Government support farmers when making
those financial decisions towards more climate resiliency?
Thank you.
Mr. Duvall. Well, thank you for the question, Congressman,
and you are exactly right. Other than trying to figure out how
some of these programs are going to work, and what regulations
come along with it and the burden that comes with it, is the
cost. You are exactly right. What is it going to cost me to put
this practice on the ground? What new equipment am I going to
have to buy? And then, you are exactly right. My membership
goes from small, medium, large, different size organizations. A
large organization might can afford that $200,000 piece of
equipment, but a small operator can't and it makes it just not
feasible for him to do that.
If we have practices or we have policies put in effect, we
have to make sure that there are monies that follow that
practice or that policy, monies that are going to help farmers
and assist them in order to put those practices on the ground.
And whether it is all Federal Government or whether it is
private or public together, and how all that fits together,
someone else would have to figure that out. But you are exactly
right. It is very expensive for some of those new projects to
get put on the ground, and the new policies that are going to
be put into effect. There needs to be money to follow it. If
Americans and the rest of the world want agriculture to be the
answer to this problem, then we got to have partners to be able
to meet those obligations that we are going to have to meet to
be successful and do it.
Mr. Harder. Well said, Mr. Duvall. Thank you for that.
We look forward to working with you. We have some strong
partners with our local Farm Bureau, and I think there is a lot
of interest. That is the good news. I mean, I think folks want
to be able to adopt 21st century technology, 21st century
practices. They just want to know how to pay for it, and I
totally get that. I mean, it has to make business sense, and
the question is, as legislators, how can we help them have it
make business sense? And I think we are looking forward to
working with you on some ideas for that.
Thank you so much for your time, and I yield back the
remainder, Ms. Adams. Thank you.
Ms. Adams. Thank you.
I want to recognize the gentleman from Kansas, Mr. Mann,
you have 5 minutes.
Mr. Mann. Thank you for the time.
Thank you, Chairman Scott, for your remarks about ensuring
that agriculture is in the pole position in these discussions,
and that we highlight the climate solutions that are produced
by agriculture while our producers feed, fuel, and clothe not
only the country, but really the world.
I proudly grew up on a farm in Quinter, Kansas, population
800. I was the fifth generation to live in my house. My folks
and my brother still run our farming operation. We raise corn,
milo, wheat, had a feed yard, spent thousands of hours on a
tractor combine, doctoring sick calves, really a privilege to
get to grow up there. And I think it is important in these
discussions that we all remember that agriculture also is the
lifeblood to keeping a lot of our basic values alive that we
hold dear in this country. Those values being faith, family,
looking out for our neighbors, working hard. The values that
are central to us as Americans are supported by agriculture,
which makes these discussions all the more important.
I proudly represent the big 1st District of Kansas, one of
the biggest ag producing districts in the country. We are
number one in the country on beef production. We are number one
in the country on wheat production, number one on sorghum
production, number three on corn production. We also have
biofuels, food processors, dairies. It is a privilege and honor
to get to represent these groups.
My question also is for Mr. Duvall. So, I don't know if you
remember this, Mr. Duvall. I was our Lieutenant Governor of
Kansas, and you and I were in southwest Kansas in Garden City,
and checked out some water technology farms and spent the day
together. I really enjoyed that day. It would have been almost
2\1/2\, 3 years ago.
One of my big takeaways--and my question will be for you,
Mr. Duvall, like I said, is--and I think one thing we got to
continue to highlight is we all should be encouraged to hear
about the strides that American farmers and ranchers have made
in addressing and mitigating carbon, especially with the
reduction of agriculture's share of greenhouse gas emissions
from 24 percent in 2010 all the way down to ten percent here in
2019. So, in 9 years we have gone from 24 percent down to ten
percent. Remarkable. And I guess my question for you, Mr.
Duvall, is can you explain how that reduction was made by
farmers and ranchers in the U.S. in your mind, even as they
continue to provide a safe, reliable, and affordable food
supply? It is an amazing accomplishment and we need to keep
highlighting it. I am just curious to know your perspective.
Many of your members were part of that, and how do we go about
accomplishing that?
Mr. Duvall. Sure, and there is not one answer that answers
that question, because we have talked about all of them here,
the opportunity to participate in the programs through the USDA
that are partnerships and incentive-based. Our farmers have
latched on to that.
Technology that has come from the research from--whether it
be the plant and how we can not have to disturb the soil to get
rid of weeds, but we can control them with other products, and
we can do it with GPS and in precision plant farming. So, we
have just come a long way in the techniques that we use, and we
can do that because of the technology. We could go so much
further if we go back and talk about streamlining the approval
of these new technologies coming, increase the research. And we
can even do more to not just lower our emissions, but to help
take in--take care of some of the problems of the emissions
from other areas of other industries.
So, there is not one answer that answers that question. Our
farmers are resilient, and they are technical savvy, and they
will take advantage of every opportunity, and we have to have
broadband to make sure that we can take care--utilize the new
technology that is coming in the future, because precision
agriculture is here, and our farmers aren't wearing overalls
anymore. They are carrying computers and iPads around with them
to get the job done, and broadband is important.
And your part of the state and that travel--that visit was
wonderful. I absolutely fell in love with that part of our
country.
Mr. Mann. Well, glad to have you, and you really touched on
my next question, and that is, in my view, rural broadband has
got to be a part of this discussion, because to really continue
to improve on carbon, we have to have precision agriculture and
rural broadband is the technological underpinning of that. So,
I could not agree with you more, Mr. Duvall.
Thank you for all of our panelists today. I really
appreciate your time. And with that, I yield back.
Ms. Adams. Thank you. I want to recognize now the
gentlelady from the State of Washington, Ms. Schrier. You are
recognized for 5 minutes.
Ms. Schrier. Well, thank you, Madam Chair.
Some of the biggest concerns that I hear from farmers in my
district in Washington State have to do with concerns about
declining snowpack year over year, and therefore, less reliable
water resources for irrigation that will only worsen over time
because of our changing climate. And that is why researchers
out of Washington State University's Tree Fruit Research and
Extension Center in Wenatchee, Washington are exploring ways to
sustainably secure and more efficiently use water. And their
goal is, of course, to help farmers and growers produce food,
given scarce and unpredictable water resources. And they have
actually discovered that grape growers can achieve better
yields with less water. So, with the changing climate, we do
need both resilience and adaptation.
Now, I want to focus on regenerative farming, which has
been discussed so thoroughly today, and mostly how the Federal
Government can support farmers. So, as discussed, regenerative
agriculture refers to a constellation of practices like crop
rotation, cover crops, and no- and low-till farming that
improves soil health, sequesters carbon, reduce the need for
fertilizer and water inputs, improve yields, and also help
mitigate and adapt to climate change.
Now, these practices help farmers and are also key elements
in addressing climate change. So, farmers are driving, as we
have heard today, so much of the innovation and leading the
efforts to expand these practices, and after up front
investments, these are win/wins for farmers, as we heard from
Mr. Brown.
But there are big front-end expenses, like drill seeding
machines, and the payoff often doesn't happen until about 6
years later. And I am really excited by the Biden
Administration's commitment to climate solutions, including
these agricultural solutions. So, what I would like to ask is
how the USDA programs can help scale up? For example, the
USDA's EQIP Program provides financial and technical on the
ground assistance for conservation and regenerative
agriculture.
And so, I guess my question first is to President Duvall.
Could you say how else can the Federal Government help, and how
could we ensure lasting help that could get farmers all the way
through those 6 years?
Mr. Duvall. Well, of course you are exactly right. It takes
a tremendous investment to move in the direction. Even Mr.
Brown admitted that he took advantage of some of those
programs, and then earlier, I made the statement--and I know it
is true--that there are farmers that want to participate, but
there are not enough funds there to do it. And you are exactly
right. That no-till machine, it costs a lot of money, and if
you are not a medium- or large-sized farmer, you may not be
able to afford that.
Ms. Schrier. I even asked farmers if they could share. Like
if you could have one for the entire town, and you can't do
that. They all plant at the same time.
Mr. Duvall. Well, soil and water conservation district here
owns one, and you can rent it from them. There is sharing going
on, and that is a program that is very well-used here in my
community.
There are ways to do this, we just have to explore how to
do it. But there are more people wanting to be involved in it.
They are interested in doing it. They just want to--they don't
want anybody to force it on them. Because every farm is
different, and I think Mr. Brown made the point that his
techniques work anywhere in the world. I don't disagree with
that, but there are a lot of differences in soils and regions
and weather patterns and everything else. Some work good, some
work better, and we just have to--we can't have one thing that
fits all.
Ms. Schrier. Absolutely. Thank you.
I want to ask a little bit about carbon credits, but I
don't know that I have time for that. Can I ask just maybe in
30 seconds, maybe Mr. Brown, can you tell me a little bit about
biochar and whether that is being implemented? Whether that is
something that can even be scaled?
Mr. Brown. Thank you. Biochar is certainly a tool that can
be used in the right context. Again, it comes back to carbon.
So, in your situation, obviously in Washington State, you have
sources of that carbon available where biochar could be made. I
would use that as a tool starting out. I would look at the
Johnson-Su bioreactor of adding biology, and then also a hidden
gem you have is the Bread Lab there in Washington State. The
work that Dr. Steven Jones is doing is just unbelievable with
granule grains.
Ms. Schrier. Oh, fantastic. I have one more thing. I am
running out of time, which is just that I agree with everybody
today that we need to have farmers at the table, and that is
why I have invited Robert Bonnie, USDA's Deputy Chief of Staff
for Policy and Senior Advisor on Climate to my district in
order to sit down at a roundtable with my farmers to talk about
climate policy, the good, the bad, and the ugly, and our
farmers need to be at the table.
I would like to submit that letter for the record.
[The letter referred to is located on p. 387.]
Ms. Adams. So ordered.
Ms. Schrier. Thank you. I yield back.
Ms. Adams. Thank you.
I want to recognize the gentlelady from Illinois,
Representative Miller, you are recognized for 5 minutes.
Representative Miller? Okay. All right, the gentlelady is not--
I don't see her. Okay.
I want to recognize now the gentleman from Alabama, Mr.
Moore. You are recognized for 5 minutes, sir.
All right. The gentlelady from Florida, Mrs. Cammack, you
are recognized for 5 minutes. The gentlelady--is Mrs. Cammack
here, gentlelady from--okay.
The gentlelady from Minnesota, Mrs. Fischbach, you are
recognized for 5 minutes.
The gentleman from New York, Mr. Jacobs, you are recognized
for 5 minutes, sir.
The gentleman from Iowa, Mr. Feenstra, you are recognized
for 5 minutes. Mr. Feenstra?
The gentleman from--is that Iowa? No, the gentleman from
North Carolina, Mr. Rouzer. You are recognized for 5 minutes,
sir.
The gentleman from Ohio, Mr. Balderson. You are recognized
for 5 minutes. Okay.
Let me go to the gentleman from California, Mr. Panetta.
Mr. Panetta, you are recognized. Go ahead, sir.
Mr. Panetta. Thank you, Madam Chair. Am I good to go?
Ms. Adams. You can go ahead, yes.
Mr. Panetta. There you go. Thank you. I appreciate that. I
am fortunate to have sat down in my seat.
Thanks to all the witnesses for being here. I appreciate
your preparation and your contribution. I know it has been a
long hearing, and I appreciate your patience with this. So, I
appreciate your preparation, and of course, your participation
in a very, very important hearing. And obviously, thanks to the
Chairman for holding it, as well as the Ranking Member, ``GT''.
Look, I think if there is anybody concerned--at least in my
experience with my producers on the Central Coast of
California, if there is anybody concerned with fresh air,
healthy soils, and clean water, it is our producers. And I
think that has been made evident today with the similar
sentiments that have been expressed, not only from our
witnesses, but from the Members on both sides of the aisle.
I believe in my conversations and my work with my ag
producers, they value and understand the concept that maybe
some of you have or have not heard about. It is called
usufruct. And basically, it is the temporary right to use the
land, usus, to produce fruit, fructus, usufruct. And what that
means is that they--I believe our producers understand that
they are here. They use the land, but they also have to
preserve it for our future, because they know it is not theirs.
It is a temporary right. And that is important, because I
believe that when it comes to dealing with the climate crisis,
I can tell you, our producers understand that and our
producers, therefore, as we have heard throughout this hearing,
need to be at the table.
And I also want to give a shoutout and acknowledge our new
USDA Secretary Vilsack for his vision to ensure that our
farmers are at the table. And I believe it is our obligation to
ensure that our producers, especially mine on the Central
Coast, many, many specialty crops, are at the table. And as
many of you have heard me say--and it is the first full--well,
second hearing in which we are having at this Agriculture
Committee, I can say people know that I come from the Salad
Bowl of the World, and therefore, we have a number of specialty
crops. And so, obviously those types of producers have been
progressive when it comes to maintaining and preserving the
earth that they use to produce their fruits and vegetables.
And so, I want to just focus on Mr. Brown right now.
Obviously, when it comes to specialty crops--I know you are
from North Dakota. My wife is from North Dakota up in Rugby.
There are not many specialty crops up there, but when it comes
to specialty crops, what type of smart agricultural efforts are
there when it comes to their concern for climate crisis?
Mr. Brown. The same principles apply, whether we are doing
specialty crops, lettuce, salads, vegetables, fruits. We are
working extensively in California working with your growers--I
am sure some of them are--and the technologies they are using
are these technologies to use these principles in order to
lower their input costs. And they can do that. There was a
previous comment that it takes 6 years to recoup the costs.
That is not true at all. We are seeing significant savings by
year 2, certainly by year 3. So, the same principles apply.
Mr. Panetta. Okay. Let me pivot to Ms. Knox. Would you
agree?
Ms. Knox. Yes, I think there are a lot of immediate
benefits. I mean, it doesn't take a long time to see benefits
to the soil. It doesn't see--a long time to see other benefits
to specialty crops. Here in Georgia, we are seeing people try
new crops. We are growing satsuma mandarin oranges, and we are
growing olives. You don't really think of Georgia as being a
place to grow olives, but we do have a chance to expand into
new areas that could be new markets, and to take advantage of
that.
But growing them regeneratively is definitely going to help
the producers in the long run, because it will reduce the
number of inputs.
Mr. Panetta. Thank you.
And speaking of Georgia, let me say hello to my friend,
President Duvall. Obviously--let me first acknowledge the fact
that he understands that the number one issue of agriculture
right now is labor, and how important that is. However, we do
have to deal with this climate crisis as well.
And so, President Duvall, tell me how the American Farm
Bureau has reached out to our specialty crop producers to
ensure that they are at the table as well when it comes to
coming up with a solution, or the many solutions that we have
to come up with for dealing with the climate crisis in the
field of agriculture production?
Mr. Duvall. Congressman, ever since I have been at the
American Farm Bureau, I have encouraged inclusiveness. That
means all kinds of agriculture, all genders, all races to come
to the table, because you know, it is our job and our mission
to be able to provide one united voice of the American farmer.
How can we do that without all of them being there? So, we have
been pretty successful and----
Ms. Adams. The gentleman is out of time.
Mr. Duvall. Look, we are not here just to represent big
agriculture, but we need you to come to the table and give us
your ideas, and that is what we are trying to do.
Ms. Adams. Thank you.
Mr. Panetta. I look forward to being at the table with you,
President Duvall.
Thank you, Madam Chair. I yield back.
Ms. Adams. Thank you. Are there any Republicans that I
can't see that need to be recognized? Okay, then we will move
on to the gentlelady from Iowa, Mrs. Axne. You are recognized
for 5 minutes.
Mrs. Axne. Thank you, Madam Chair, and thank you to
Chairman Scott just for holding this hearing that is so
important. It is such a pressing issue, and I really appreciate
our witnesses being here today to share your expertise. I very
much appreciate the testimony given and the discussions around
how much our environment has been affected by climate change,
and how substantial that cost has been.
Jim, you noted in your testimony the increasing number of
climate events that result in costs exceeding $1 billion, and
what a shocking number: 22 events last year. But unfortunately,
as you mentioned, those events have become all too common for
folks back in my home State of Iowa. We are the ones who had
the derecho sweep across our state, and when Iowans don't know
what a storm should be called, it is definitely something out
of the ordinary. And of course, we saw millions of farmland
acres destroyed, left hundreds of thousands of Iowans without
power. And then just a year prior to that in southwest Iowa in
my district, we saw devastating flooding along the Missouri
River, which destroyed homes and farmland up and down the
river. And honestly, we simply cannot afford to accept that
these events are the norm, and we have to take action on this
climate crisis to reduce our carbon emissions and build up
resiliency so that our farmers can be successful.
So, my first question is to you, Mr. Brown. Thank you so
much for sharing with the Committee the successes that you and
others have experienced as a result of sound soil health
practices. I was reading your written testimony, and I was
taken by the story of Mr. Adam Grady from North Carolina. Two
weeks after waters receded from Hurricane Florence, Mr. Grady
was already seeding his fields. Like Mr. Grady, farmers in Iowa
are facing increasing challenges combating excess moisture each
year as a result of more frequent wet springs.
Mr. Brown, can you just take a moment to describe how the
soil health practices can help farmers adapt to floods and the
changing climate more broadly?
Mr. Brown. Well, thank you. That is an excellent question.
I am going to hold up this jar to signify this is actually
soybean seed in a jar, but think of it as soil aggregates. So,
soil aggregate is just like one of these seeds. It is a little
pad of sand, silt, and clay bound together. Water: your
infiltration rates of water depend on those soil aggregates. A
soil aggregate will only last about 4 weeks, and then new ones
need to be built. In order to build new ones, you have to have
soil biology. You have to have mycorrhizal fungi.
We were holding a soil health academy there in southeastern
Iowa, and they were bragging about the very rich soils of
eastern Iowa. Unfortunately, they had \1/2\" of rain and that
water could not infiltrate.
You mentioned the flooding problems we are seeing along the
Missouri and Mississippi Rivers, here in North Dakota, the Red
River. Year after year we combat that. What we need to do to
alleviate that is build soil aggregates. We can help alleviate
our flooding, alleviate those costs that occur year after year,
as you said, to society if we focus on the resiliency of our
soils. We are not doing that anymore. I travel extensively, all
50 states, and I have taken soil test after soil test after
soil test that shows that we no longer have the ability to
infiltrate water.
In 2009, we had a major rainfall event on my ranch. We had
12.6" of rain in 6 hours. The next day, I could go out in my
fields and drive across them with the tractor and not leave a
rut. It is all about biology and building back resiliency
through soil health.
In Iowa, they can certainly do that with the wonderful
resources you have there.
Mrs. Axne. Well, I appreciate that, and it is inspiring to
hear this, and thank you.
As your work as a farmer and educator takes you around the
country, as you mentioned, what do you think are some of the
biggest reasons that you hear from farmers that prevent them
from adopting these soil health practices, and what technical
and financial resources do you think are needed for us to
encourage to scale up adoption of these practices?
Mr. Brown. That is a wonderful question, one I get asked
daily.
The number one reason is fear. For farmers and ranchers it
is fear of the unknown. Again, it goes back to education. The
second is the current farm program. The current farm program, I
am sorry, but it is not conducive to adopting these practices.
We make small steps through NRCS and that, but then the
production model is wrong. We are on a path through Risk
Management Agency where the crops seeded revenue insurance
determines 95 percent of what farmers and ranchers plant.
Because they have to obtain operating money, operating notes
from the bank in order to stay in production that year, that
bank is going to tell them you have to take part in this
program, and then you have to plant those crops that will allow
you the greatest return through risk management.
Don't get me wrong; we need crop insurance----
Ms. Adams. The gentleman is out of time.
Mr. Brown.--we need risk management, but it has to be
changed. Thank you.
Ms. Adams. Now, I want to recognize the gentlelady from
Florida, Mrs. Cammack. You are recognized for 5 minutes, ma'am.
Mrs. Cammack. Thank you so much, and good afternoon. I
would like to thank the witnesses for hanging in there on this
long hearing today and appearing before the Committee. I would
also like to start by asking everyone who has had a meal today
to please thank a farmer.
While we have this important discussion about the
environment, climate, and U.S. agriculture, it is important to
remember that the realities already facing our farmers are
pretty grim. Growers in my home State of Florida and those
throughout the country continue to face a number of challenges
to remain competitive in the face of rising foreign imports.
These imports are not grown under the same high environmental
standards adhered to by U.S. producers including standards for
air, water, solid and hazardous waste, and not to mention the
labor standards. This conversation about what more farmers need
to do in order to protect our environment becomes a bit
trivial, in my opinion, when our farmers are forced to add to
food waste because they can't compete with cheaper imports, as
I just saw last week in south Florida when our producers had to
disk up crops simply because they could not compete with cheap
imports. The disparities when it comes to labor, regulatory,
and environmental standards have left our producers at a
tremendous and devastating disadvantage.
So, I would like to start out with Mr. Duvall. Thank you
for being here with us. For the record, if you can, and in one
word, from what you have seen, which country produces on a
large scale the highest quality agricultural products with the
lowest environmental impact?
Mr. Duvall. The United States of America.
Mrs. Cammack. I love that answer. And as a follow-up to
that, Mr. Duvall, and in the same format, in terms of
inequitable competition, which country poses the largest threat
to American agriculture?
Mr. Duvall. In your area, Mexico.
Mrs. Cammack. Thank you.
Mr. Duvall. Over-dumping product into your state.
Mrs. Cammack. Absolutely, thank you.
Ms. Knox, you mentioned in your testimony that the
environmental impact that the clearing of land has on the
release of carbon dioxide into the atmosphere. I want to ask,
do you agree that it is more environmentally conscious to
support our local producers here in the United States, rather
than foreign producers held to looser regulation?
Ms. Knox. I think supporting local farmers is always an
important thing to do. It minimizes the cost of transportation
to help support the local economy, and so, I--and they really
farm more responsibly in a lot of ways, because we are more
strict about our regulations. And so, I really support local
farmers because of that.
Mrs. Cammack. Excellent. Thank you, Ms. Knox, and I have to
say go Gators, just because--well, you know why.
Now, Mr. Brown, as you know, many American farmers are
ready and willing to participate in carbon sequestration and
implement regenerative agriculture. I have seen a clear desire
to embrace these practices in my home State of Florida;
however, I have also seen farmers frustrated by the prohibitive
costs associated with implementation. In my district alone, we
have producers that are forced to spend anywhere up to the tune
of $300,000 just to participate in a carbon sequestration
program. In your opinion, how can we make carbon sequestration
and other green infrastructure investments more affordable for
America's producers?
Mr. Brown. Well, they should not be participating in that
program if it is costing that. It is about much more than
carbon. Farmers and ranchers need to be paid for all ecosystem
services. We are talking about carbon, but it is much more than
that. It is clean air, clean water. It is taking nutrients out
of the watersheds, holding them on the farm where they belong.
The way to do that is using the USDA programs to
incentivize best use practices, and to educate those farmers
and ranchers.
Mrs. Cammack. Thank you.
Mr. Shellenberger, you have done a tremendous amount of
research and work developing your book, Apocalypse Never. Since
I have about 40 seconds left on the clock, I would like to give
you my remaining 30 seconds to give an elevator pitch as to why
people should read your book, and what the biggest takeaway is.
Mr. Shellenberger. Thanks for asking.
I mean, the argument of the book is that climate change is
real, but it is not our biggest environmental problem. Our
biggest environmental problems stem from the inefficient use of
land, particularly in poor countries, and if I had more time, I
would have described all the work that I think American farmers
can do to extend the innovative, efficient, and productive
kinds of agriculture that we have developed here to poor and
developing countries, because that is really what matters in
terms of protecting natural ecosystems and lifting everybody
out of poverty, which are goals that I think we all share.
Mrs. Cammack. Thank you so much, and Mr. Cantore, I am sure
I will see you in Florida later this year.
And with that, I yield back.
Ms. Adams. Thank you.
The gentleman from Florida, Mr. Lawson, you are recognized
for 5 minutes, sir.
Mr. Lawson. Thank you, Madam Chair, and I will try to go
real quickly.
My question is going to be for Mr. Duvall. My district in
north Florida is home to so much of the state's timber industry
and working forests. Hurricane Michael in 2018 really pummeled
our area's agriculture, delivering $1.2 billion in damages to
timber. So, I am interested in policy that could incentivize
reforestation and timber production, which could especially
help producers in catastrophic events such as hurricanes.
Can you talk about the merit of intensifying sustainable
practices on these lands, and their contribution to our overall
goal of mitigating climate change?
Mr. Duvall. Yes, the forests around our country contribute
huge help to solving the problems of climate change, and we all
know that trees are the biggest sequestrator of any forage that
is out there, any plant that is out there. So, you are exactly
right. To incentivize people to be more in agriculture in a
forestry area, we have to make it profitable again. The only
way to make a living on forestry is to have tens of thousands
of acres and not all the farmers have that. Very few have that,
and the management tools that they use, our state forestry
units are kind of confined with the resources. There is not
enough money there to help people go out and--technicians to go
out and help them put those practices on the ground, whether it
be state or Federal. But I think that would be a huge help if
USDA could help assist that.
You come to your part of the country, my part of the
country, we don't have forest fires because we manage our
timber. We burn off that fuel. We make sure that that fuel is
not there to harm all the homes that are around it. The
management in forestry is vitally important, not just to being
productive and not burning, but it is also important to
sequestering carbon.
Mr. Lawson. Okay, thank you very much.
Ms. Knox, from tomatoes, citrus, specialty crops are
critical in the Florida economy. Our land-grant institutions
are doing great research to address these to our crops. I am
concerned that climate change will only make the battle more
difficult. Can you please go into a bit more detail regarding
potential impact that climate change would have on, especially,
specialty crops?
Ms. Knox. I think climate change will affect them in a
variety of ways. I think as temperatures go up, there may be
some specialty crops that are not going to grow well in
Florida, and they will look for new varieties that may be able
to keep better. I think they are going to also worry a little
bit about water availability, although as I understand it now,
a lot of the specialty crops in Florida are already under
irrigation, so there would be a question of will there still be
water available? But I think that is probably not as important.
I think one of the other issues is as the growing season
increases--of course, part of Florida has a year-round growing
season, but other parts still do see frost. We are going to see
increases in the number of pests, and those pests aren't only
coming locally, but they are also being blown in from other
places, and we don't really know yet what the weather patterns
are going to do as far as the wind shifting over time. And so,
that is certainly something that could also be more than it
shows. We get more of these pests and diseases that are blowing
in and certainly affecting some of the specialty crops.
Mr. Lawson. Thank you, Ms. Knox. That was really great to
know.
And with that, Madam Chair, I yield back.
Ms. Adams. Thank you.
The Committee will recess subject to the call of the Chair.
[Recess.]
The Chairman [presiding.] Thank you. Our Committee will
come back to order. We are getting around to the finishing
line. I can't thank everybody enough for hanging in there with
us. It lets you know how serious everybody is about this very
serious issue we are facing on climate change. Thank you for
tolerating our interruptions, particularly our panelists who
have been with us here since 12. Great. I really, really
appreciate you.
Now, we are going to finish up with our hearing. We have, I
believe, Mrs. Fischbach from Minnesota. You are now recognized
for 5 minutes.
Mrs. Fischbach. Yes, sir.
Thank you so much, and I hope everyone can hear me.
First of all, thank you, Mr. Chairman, and I would
especially like to thank all of the panelists for hanging in
there with us. It has been an interesting day of running back
and forth and all kinds of other things happening here, but
thank you so much for hanging out with us.
Mr. Chairman, there is no doubt that our changing weather
patters presents challenges for farmers and ag producers, but
while addressing those challenges, we must do so in a way that
respects the industry and recognizes their achievements
protecting our environment. Adding more regulations or pushing
lopsided partisan measures is not the answer. Instead, we
should incentivize farmers to adopt what many of them already
do through innovation and ingenuity. The soils they cultivate
better protect against erosion and nutrients lost. The
equipment they use is far more efficient than just a few years
ago, and farmers are utilizing technology to minimize inputs
and further reducing their footprint.
There is a challenge that must be met without partisan
agenda. All of us agree that we each have a role in protecting
our environment and farmers are some of the best stewards of
our lands and resources. The farmers and producers I know want
to be partners in this work, but nothing meaningful will happen
by enacting punitive measures that malign their hard work, and
it will happen by affording them the respect they deserve.
That being said, Mr. Duvall, I firmly believe that any
climate proposal that doesn't include biofuels in part of its
calculus is not a serious proposal. This homegrown American
energy source is a vital part of my district's economy, and
many others of this Committee. Can you speak a little bit to
the benefits of this product in reducing our emissions, and
where it does fit in the climate-related proposals?
Mr. Duvall. You are talking about renewable energies?
Mrs. Fischbach. Yes, biofuels in particular, I am sorry.
Mr. Duvall. Yes, ma'am. I mentioned earlier to another
question that we need to make sure that we recognize that this
country went and asked agriculture to be a part of our energy
independence solution, and we are a piece of that pie. And the
infrastructure around that is so important. About 30 percent--I
stand corrected if I am wrong--but I think about 30 percent of
the corn and 30 percent of the soybeans goes to biofuels, and
now we are generating enough that we can even export it. It has
been a tremendous lift to your part of the world and the
Midwest, and it has not only helped the farmers, it has helped
rural communities and kept them vibrant. And anything we do to
hurt that industry is going to be devastating to that part of
our country. So, we would not support anything that would hurt
that infrastructure and the biofuel.
Mrs. Fischbach. And Mr. Duvall, I appreciate that.
Mr. Shellenberger, we just touched a little bit on some of
the issues of broadband, and I am just wondering if you can
comment on how that increased broadband connectivity plays a
role in the discussion, and how it relates to the precision
agriculture technology?
Mr. Shellenberger. Yes, great question. I totally agree
that it is essential what we have been seeing with the
revolution in precision agriculture is the application of GPS
and high-processing computers to be able to take efficiencies
and productivity to the next level. So, yes, I think it is
obviously in the public interest to support that expansion and
it seems like a no-brainer from my point of view.
Mrs. Fischbach. Well, and I will just comment on our last
Committee hearing, I was dialing in remote from home and I had
some connectivity issues, so it made quite the point that day.
But I will yield back the remainder of my time. Thank you,
Mr. Chairman.
The Chairman. Now, Mr. Randy Feenstra from Iowa, 5 minutes.
Mr. Feenstra. Thank you, Mr. Chairman, Chairman Scott and
Ranking Member Thompson.
First, I want to thank each of the witnesses for their
testimony today. It is very important that we discuss how
farmers, ranchers, and the agricultural industry have already
been leading the world in reducing the environmental footprint
and additional opportunities that exist for their continued
leadership.
I would like to quickly note that in Mr. Cantore's
testimony, he made mention of the devastating derecho storm
that impacted Iowa last year. While I believe this Committee
must work to understand how we can help the agriculture
industry to mitigate and be resilient against disasters, we
must also ensure that we provide timely relief for producers
devastated by damage. And this is something that I have been
actively working on.
With that, this question would be for Mr. Shellenberger.
So, getting back to climate change, Iowa's agriculture
community has been a leader in addressing climate change. I
believe that biofuel production, just like Ms. Fischbach noted,
and Iowa in the 4th District should be a leading--be made a
leading role in the efforts to reduce carbon emissions. It is
also important to recognize the potential of biofuels to
further reduce the carbon intensity with the potential to be
net carbon negative. Let me say that again. Biofuels can make
things net carbon negative, unlike electric vehicles,
especially if the Federal Government helps companies to
implement innovative technologies.
Green Plains Incorporated just announced last week that
three of their bio-refineries, including the plant in Superior,
Iowa, have entered into a carbon capture and sequestration
project. In short, the project will transport CO2
from Iowa to North Dakota for the deposit in their geological
storage. This will allow these bio-refineries to reduce their
carbon intensity by as much as 50 percent, comparable or lower
than the other low carbon fuels available on the market today.
Green Plains Incorporated cited that section 45Q tax credits as
being important to allow the company to invest in these
innovative technologies.
So, Mr. Shellenberger, I think this aligns with your
testimony's theme of encouraging technological innovations as
an answer to climate change, instead of burdensome regulations.
Could you discuss other incentives like the section 45Q credit
that you believe would be helpful to drive innovation in the
agriculture industry to reduce carbon emissions?
Mr. Shellenberger. Sure. Yes, I mean, I think all of those
investments are important, both for carbon sequestration and
for biofuels. I think in the past, we have over-subsidized the
production of biofuels when I think more targeted R&D was
merited, so I haven't looked at the specific projects you
mentioned, but clearly, this kind of cooperation to solve
specific problems I think is the way to go. There are some
calls that have been made for kind of generic increases of
innovation that I don't think make as much sense. But I think
we have seen, obviously, with the coronavirus vaccine and the
Shale gas revolution, nuclear power, genetically modified seed
technologies that when we have a specific objective that we are
trying to achieve, that the public- and private-sector can come
up with some really remarkable innovations. So, I think that
those are all great directions to be going in.
Mr. Feenstra. Thank you, Mr. Shellenberger.
So, if you could--just a little more--would it be more
beneficial--I mean, you think of biofuels and if you could make
something net carbon negative, wouldn't that be the paramount
structure of what we all desire?
Mr. Shellenberger. It would. I think the challenge with
biofuels, as you know, we have had a challenge in terms of
counting the carbon sequestration and emissions in the past.
There has been a pretty significant debate about whether
clearing land for biofuels actually results in a net loss or a
net gain of carbon emissions. So, I just think it is an area
that we need to proceed with some amount of caution, because I
do think we have seen biofuels scaled up in the past that have
not really panned out in terms of their benefit. So, I think we
need to take a close look at which of the biofuels we are
using, and how we are doing those calculations.
Mr. Feenstra. Sure. Thank you.
But wouldn't that be the same for electric vehicles? I
think that exactly what you just said would be noted for
electric vehicles also. Would that be a fair statement?
Mr. Shellenberger. Absolutely, and there is a very active
debate within the energy analysis community about whether
electric vehicles are going to be the right solution, or
whether it would be hydrogen-powered fuel cell vehicles. There
are good arguments on both sides. I am personally agnostic
about it. I think they have to be decided on a case-by-case
basis. There are reasons to think that hydrogen is the way we
will be going in the long-term, but again, I just think it is a
little bit too early to say.
Mr. Feenstra. Well, thank you for your comments, Dr.
Shellenberger. I greatly appreciate them. I am still a believer
that the combustion engine can do great things, as long as we
can provide a negative carbon footprint.
Anyway, thank you. I yield back my time.
The Chairman. Well, thank you so much, and let me just say
how grateful and just how thankful we all are on this Committee
for the outpouring of help and knowledge and information,
accurate, that will help us that you five experts have given to
us today. We thank you for the time that you have put in. This
has been a long and thorough hearing.
But let me just tell you the great good that you all have
done too this day, because as I said in the outset, our whole
thrust forward to deal with climate change must be anchored in
agriculture. That is the major and critical thing we have
established today. And that is what is important.
So, to you, Mr. Jim Cantore--and I think I got your name
right--the senior meteorologist--and I hope I got that one
pronounced--of The Weather Channel, thank you. Thank you so
very much.
Ms. Pamela Knox, Director of the University of Georgia's
Weather Network, thank you for your piercing insights that you
gave to our Committee.
And to Zippy Duvall, my good friend and fellow Georgian,
President of the American Farm Bureau Federation, thank you.
You brought such great insight directly from the perspective of
our farmers. They are the ones that we want to make sure our
climate change is based upon making sure our farmers are not
only at a seat at this table for climate change, but at the
head of the table. Our farmers.
Mr. Gabe Brown of Brown's Ranch, the Brown's family ranch
from Bismarck, North Dakota, thank you so much. You brought
such great wisdom and information of which many of us were only
dimly aware on this Committee. Thank you for that.
And also, I mentioned Mr. Gabe Brown from Bismarck, North
Dakota. And Mr. Michael Shellenberger, President of
Environmental Progress. The five of you have done a wondrous
benefit, not only for this Committee, but for the nation. We
have received information that literally thousands of people
across this country were tuned in to this hearing, and that is
what is important.
So, from the bottom of my heart and the bottom of the heart
of our Agriculture Committee here, we just want to say thank
you, and God bless you.
Now, I turn it over to you, Ranking Member, for your
closing remarks.
Mr. Thompson. Well, thank you, Mr. Chairman. Thank you to
our witnesses. They did just a tremendous job. And I have to
say, an impressive turnout by our Members on both sides of the
aisle participating in this. I know we went long, but that is
because it shows the passion and the interest of the Members.
Thank you, Mr. Chairman. I thought it was an efficiently run
hearing. You got that much interest, and I think we are going
to have long hearings because of the commitment of the Members
that we have on the Agriculture Committee.
United States agriculture is the most productive and the
most successful at mitigating greenhouse gases than anywhere
else in the world. Our goal must be a healthy environment and a
healthy economy. You cannot compromise one over the other.
Anything that we do needs to be both good for the environment
and for the economy. And that, quite frankly, means the
economics of our farm and ranch families, money in their
savings accounts and their checking accounts as well.
Agriculture has the solutions. U.S. agriculture has the
science, and U.S. agriculture has the proven outcomes when it
comes to this topic of climate. Our focus should be climate
solutions that are based on science, innovation, technology,
and voluntary led conservation. That defines American
agriculture.
So, thank you, Mr. Chairman, and I yield back.
The Chairman. Well, thank you, and before I adjourn, of
course, none of this would have happened had it not been for
our great staff, Ranking Member, and I am speaking on your side
and mine. They worked night and day to pull this hearing
together, and I tell you, I want to say just a big thank you to
our great staff here in the Agriculture Committee for the great
work that they have done.
Mr. Thompson. I certainly agree. They make us look pretty
good.
The Chairman. I think so.
So, with that, then this hearing comes to an end, and thank
you all very much for your participation.
Thank you.
[Whereupon, at 5:31 p.m., the Committee was adjourned.]
[Material submitted for inclusion in the record follows:]
Submitted Articles by Hon. David Scott, a Representative in Congress
from Georgia
Article 1
[https://ehp.niehs.nih.gov/doi/10.1289/EHP41]
Environmental Health Perspectives
Estimated Effects of Future Atmospheric CO2 Concentrations
on Protein Intake and the Risk of Protein Deficiency by Country
and Region
[Is companion of Estimated Deficiencies Resulting from Reduced Protein
Content of Staple Foods: Taking the Cream out of the Crop? (https://
ehp.niehs.nih.gov/doi/10.1289/EHP2472)]
Danielle E. Medek,1, 2 Joel Schwartz,\1\ and Samuel S. Myers
1, 3
---------------------------------------------------------------------------
\1\ Department of Environmental Health, Harvard T.H. Chan School of
Public Health, Boston, Massachusetts, USA.
\2\ Waitemata District Health Board, Takapuna, Auckland, New
Zealand.
\3\ Harvard University Center for the Environment, Cambridge,
Massachusetts, USA.
Address correspondence to D. Medek, North Shore Hospital,
Shakespeare Ave., Takapuna, Auckland, New Zealand 0622. Telephone:
6494868900. Email: [email protected].
Supplemental Material is available online (https://doi.org/10.1289/
EHP41).
The authors declare they have no actual or potential competing
financial interests.
Received 27 February 2016; Revised 12 September 2016; Accepted 19
September 2016; Published 2 August 2017.
Note to readers with disabilities: EHP strives to ensure that all
journal content is accessible to all readers. However, some figures and
Supplemental Material published in EHP articles may not conform to 508
standards due to the complexity of the information being presented. If
you need assistance accessing journal content, please contact
[email protected]. Our staff will work with you to assess and
meet your accessibility needs within 3 working days.
---------------------------------------------------------------------------
Abstract
Background: Crops grown under elevated atmospheric CO2
concentrations (eCO2) contain less protein. Crops
particularly affected include rice and wheat, which are primary sources
of dietary protein for many countries.
Objectives: We aimed to estimate global and country-specific risks
of protein deficiency attributable to anthropogenic CO2
emissions by 2050.
Methods: To model per capita protein intake in countries around the
world under eCO2, we first established the effect size of
eCO2 on the protein concentration of edible portions of
crops by performing a meta-analysis of published literature. We then
estimated per-country protein intake under current and anticipated
future eCO2 using global food balance sheets (FBS).
We modeled protein intake distributions within countries using Gini
coefficients, and we estimated those at risk of deficiency from
estimated average protein requirements (EAR) weighted by population age
structure.
Results: Under eCO2, rice, wheat, barley, and potato
protein contents decreased by 7.6%, 7.8%, 14.1%, and 6.4%,
respectively. Consequently, 18 countries may lose >5% of their dietary
protein, including India (5.3%). By 2050, assuming today's diets and
levels of income inequality, an additional 1.6% or 148.4 million of the
world's population may be placed at risk of protein deficiency because
of eCO2. In India, an additional 53 million people may
become at risk.
Conclusions: Anthropogenic CO2 emissions threaten the
adequacy of protein intake worldwide. Elevated atmospheric
CO2 may widen the disparity in protein intake within
countries, with plant-based diets being the most vulnerable. https://
doi.org/10.1289/EHP41.
Introduction
Globally, 76% of the population derives most of their daily protein
from plants (FAO 2014a). With projected population growth to 9.5
billion by 2050 (UN 2013), alongside dietary and demographic changes,
future nutritional demands may overwhelm global crop production
(Alexandratos 1999). Compounding the strain on food supply, plant
nutrient content changes under elevated atmospheric carbon dioxide
concentrations (eCO2) (Myers, et al., 2014).
Under the CO2 concentrations predicted in the next 50 y,
crops with C3 photosynthesis, such as rice and wheat, may
experience up to 15% decreases in grain protein content (Myers, et al.,
2014). The effects of eCO2 are less on C4 crops,
such as maize and sorghum, and on nitrogen-fixing plants, such as
legumes (Myers, et al., 2014). Thus, the impacts of eCO2 on
dietary protein intake will depend on which staples a country consumes,
their dependence on the staple for protein, and their current risk of
protein deficiency.
Protein deficiency usually co-occurs with energy and micronutrient
deficiencies (Millward and Jackson 2004). Insufficient protein intake
limits growth, tissue repair, and turnover (Gropper and Smith 2008).
Few controlled studies investigate protein deficiency syndromes in
otherwise energy and nutrient sufficient diets. In renal disease,
isocaloric protein reduction decreased lean body mass and lymphocyte
count (Ihle, et al., 1989; Klahr, et al., 1994). In elderly women,
these diets reduced cell mass and protein synthesis while impairing
muscle function and immune status (Castaneda, et al., 1995). Low
protein intake contributes to wasting, stunting, intrauterine growth
restriction, and low birth weight (Black, et al., 2008). Together with
protein-energy malnutrition syndromes, this causes an estimated 90.9
million disability-adjusted life years (DALYs) and two million deaths
annually (Black, et al., 2008).
Previous meta-analyses conducted on the effects of eCO2
on plant nutrient contents (Taub, et al., 2008; Loladze 2014) have not
assessed eCO2 impacts on edible protein from a global
dietary context, nor did they consider distributional effects within
countries. We aimed to estimate eCO2 impacts on global
protein intake, and on the proportion of the population by country at
risk of protein deficiency. We aimed to expand on the meta-analysis by
Myers, et al. (2014), including all available studies reporting
eCO2 impacts on the edible portions of crop plants,
including lesser-studied foods and studies in (sub)tropical locations.
Then, using published food balance sheets (FBS) and measures of
economic inequality within countries, we aimed to estimate dietary
protein intake under current and future atmospheric CO2. We
thereby tested the sensitivity of global protein intake and inequality
of intake to rising atmospheric CO2, identifying key regions
to target with nutritional interventions.
Methods
Systematic Review and Raw Data
We conducted ISI Web of Knowledge (https://pcs.webofknowledge.com/)
literature searches in July-September 2014 and in January 2016 for the
effects of eCO2 on the protein content of all plants listed
in the FAO FBS. This study supplements the meta-analysis of common
European/U.S. staples conducted by Myers, et al. (2014). Because
estimates of plant protein are commonly derived by multiplying measured
plant nitrogen (N) by a conversion factor, we considered published
changes in N and protein to be equivalent (Taub, et al., 2008). For the
full search string and exclusions, see ``Part 1'' and ``Part 2'' in the
Supplemental Material. A total of 119 citations were used. For
references, see ``Part 3'' in the Supplemental Material.
We included raw data from free-air CO2 enrichment (FACE)
and open-top chamber studies, with data from European wheat, barley,
and potato Changing Climate and Potential Impacts on Potato Yield and
Quality (CHIP) and the European Stress Physiology and Climate
Experiment (ESPACE) studies (A. Fangmeier, unpublished data, 1994-1999)
and Australian wheat and pea Australian Grains Free Air CO2
Enrichment (AGFACE), Japanese rice, American soy, corn, and sorghum
Soybean Free Air Concentration Enrichment (SoyFACE) and Arizona FACE
(data from Myers, et al., 2014). Raw data included free-to-air carbon
dioxide elevation (FACE) and open-top chamber studies, 41 cultivars,
nitrogen fertilizer, watering, and time of sowing treatments over
multiple years.
Response ratios (RRs) and standard errors (SEs) for protein
response to CO2 were calculated from each study's reported
error terms. When studies indicated merely significant at p<0.05 or not
significant, the SE was calculated from p-values of 0.049 and 0.1,
respectively.
Metaregression
Metaregression was performed individually for each commodity where
data were available from four or more experiments and for commodity
groups listed in the FAO FBS (Table 1). We used the statistical package
Metafor (version 1.9-4 Wolfgang Viechtbauer) in R (version 3.0.3; R
Development Core Team). For each commodity or group, the difference
between ambient (aCO2) and eCO2 treatments was
tested as a modifier. We used multivariate linear (mixed-effects)
models (the function rma.mv) with outcomes being percent decrease in
protein, and modifiers being the difference between aCO2 and
eCO2 in parts per million. Models included variance and were
weighted by replicate facilities (e.g., number of FACE rings or growth
cabinets) with random effects being year within site, and each cultivar
(and unless tested as a modifier, each watering and nitrogen fertilizer
treatment) was treated as a separate experiment. We performed Q tests
to assess heterogeneity.
Table 1. Percent change in protein content by commodity class.
------------------------------------------------------------------------
Commodity (n) Estimate [mean (95% CI)]
------------------------------------------------------------------------
C3 grains (257) ^8.14 (^12.17, ^4.1)
Wheat (166)....................... ^7.78 (^13.24, ^2.32)
Rice (66)......................... ^7.61 (^11.53, ^3.69)
Barley (21)....................... ^14.05 (^20.7, ^7.39)
C4 grains (12) 2.07 (^3.2, 7.35)
Maize (8)......................... 3.08 (^5.19, 11.35)
Sorghum (4)....................... 0.26 (^6.31, 6.84)
Root vegetable (15) ^3.42 (^8.61, 1.78)
Potato (9)........................ ^6.38 (^10.33, ^2.42)
Pulses, legumes (26) ^3.51 (^8.05, 1.04)
Peas (15)......................... ^1.69 (^3.56, 0.18)
Beans (7)......................... ^4.58 (^12.37, 3.2)
Chickpea (4)...................... ^13.47 (^21.36, ^5.58)
Oil crops (54) ^0.78 (^5.03, 3.47)
Soy (44).......................... ^0.49 (^2.92, 1.95)
Rapeseed/mustard seed (5)......... 0.92 (^8.9, 10.74)
C3 Vegetables (32) ^17.29 (^30.78, ^3.8)
Fruit (5) ^22.9 (^54.04, 8.24)
------------------------------------------------------------------------
Note: C3, crops with C3 photosynthesis; C4, crops with C4
photosynthesis; CI, confidence interval; n, number of experiments,
where each treatment/cultivar/experiment was treated as a separate
experiment, yet experiments at the same location for the same crop
were grouped together.
Meta-Analysis
Because there was no reliable dose-dependent decrease in protein
content with degree of CO2 elevation, we used meta-analysis
to derive average response ratios comparing plants grown in
aCO2 with plants grown in eCO2, where
eCO2 was in the range of 500-700 ppm. We used the rma.mv
function as for metaregression, but without the modifier term. Both
meta-analysis and metaregression tested fixed effects of pot- versus
field-grown plants and a qualitative measure of nitrogen fertilizer
treatment, categorized as low, adequate, or high, based on descriptions
in each study's experimental design. Neither modifier changed the
magnitude of the CO2 response, and neither was used in
subsequent analyses.
We minimized publication bias by including unpublished data.
Furthermore, we tested sensitivity to publication bias. For each
commodity, we incrementally added experiments with no effect of
eCO2 on protein content (RR 1, variance 0.5) until
confidence intervals for RR crossed 1. Some commodities, including
rice, were sensitive to null results, but wheat was insensitive to null
results (see Table S3).
Food Balance Sheets
The FAO FBS estimate per capita availability of each food-based
commodity (including energy and protein contents). We averaged data
over 2009-2013 FAO FBS. We assumed that protein availability equals
protein intake, corrected for digestibility (FAO 2014a). Per
convention, we assumed that plant-based protein was 80% digestible and
that animal-based protein was 95% digestible (Millward and Jackson
2004).
The ``Vegetables, other'' and ``Cereals, other'' categories were
large contributors to protein intake in some countries, and contained
both C3 and C4 plants, and for vegetables,
nitrogen fixers. We produced weighted estimates of the contributions of
each these categories, using re-calculated 2009 FBS from the FAOstat
classic platform (described fully by Smith, et al., 2015). We converted
from total grams to grams protein, using food composition tables
(Abdel-Aal, et al., 1997; USDA 2011; FAO 2012; Ballogou, et al., 2013;
New Zealand Ministry of Health 2014). We assumed that the ``Cereals,
other, not elsewhere specified'' category within the ``Cereals, other''
category was derived from C4 grains in sub-Saharan Africa,
but from C3 grains elsewhere.
To estimate the effect of eCO2 on protein intake in each
country, we assumed constant mass-based consumption of each commodity
over time, with declining protein content predicted by our meta-
analyses. We used commodity-based averages when available, and
otherwise applied the averages from the commodity group to each
commodity (Table 1). We found no studies on eCO2 response of
tree nuts, thus conservatively assumed no change in their protein
content. Likewise, we assumed no eCO2 effect on animal
protein.
Plant-Based Diets
Within a population, the lowest protein consumers also frequently
consume the least meat (see World Food Programme household surveys;
e.g., Santacroce 2008). For an extreme scenario, we reran the models,
removing all animal-sourced foods (including eggs and dairy) from the
diet, assuming no other changes in dietary fractional composition.
Intake Distribution
We assumed a lognormal distribution of protein intake within
countries (FAO 2014b), a cumulative distribution function, with the
mean,
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
and the standard deviation,
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
where x is the national mean protein intake, as estimated above, and CV
is its coefficient of variation. Because protein intake is likely to be
related to household income, we estimated the CV of protein intake
(CVprotein) from the Gini coefficient of national household
income inequality. The national Gini coefficient for household income
describes a Lorenz curve plotting the cumulative percentages of total
income against the cumulative number of households from poorest to
richest. Using linear regression, we compared per-household
CVprotein from household surveys across 36 countries (FAO
2014a) with contemporaneous national Gini coefficients (Arneberg and
Pedersen 2001; Garcia, et al., 2001; Kim and Kim 2007; OECD 2009;
Liberati 2013; USAID 2012; CIA 2014; Solt 2014; World Bank 2014). The
FAO uses Gini coefficients, gross domestic product (GDP), and food
prices to estimate CV for caloric intake (FAO 2015). We then estimated
the national CVprotein from the country's Gini coefficient
in the year closest to 2011. Owing to high uncertainty among future
economic projections, we assumed each country's future
CVprotein would remain constant.
Estimated Average Requirements
We calculated a weighted estimated average requirement (EAR) (grams
per day) for absorbed protein from the published EAR for adults (0.66g/
kg/d) and for children by age and sex, using current and mid-range 2050
demographic projections (IOM 2005; UN 2013). For adults, the minimum
safe protein intake in grams per day is based on the minimum healthy
body weight calculated from the lowest 5th percentile of body mass
index (BMI), this being 18.5 kg/m\2\ (WHO 1995). We calculated average
height from national surveys (OECD 2009; Hatton and Bray 2010; USAID
2012). Where male height was unavailable, it was calculated as 1.08
female height, based on the median male-to-female height ratio across
all countries. For child weight, the ideal body mass was the 50th
percentile by age from growth tables (WHO 2006). We adjusted EAR to
include the increased protein requirements of pregnant and lactating
women (IOM 2005) with demographics estimated from projected birth
rates, 2009 stillbirth rates and infant mortality, and breastfeeding
prevalence and duration (McDowell, et al., 2008; AIHW 2011; CDC 2011;
UN 2013; USAID 2012; Liu, et al., 2013).
Risk of Protein Deficiency
From each country's 2050 population, we calculated the proportion
and the number of people whose intake fell below the EAR under current
and eCO2 scenarios, with the difference between these
populations being our measure of impact.
We used Monte Carlo methods to propagate error from the SE of the
meta-analysis results, and for modeled CVprotein, through
the model, using 10,000 random draws from normal distributions of mean
national protein intakes, and again for error around linear regression
of CVprotein on Gini coefficient. From these two parameters, we
calculated the means (m) and standard deviations (s) of 10,000
lognormal distributions. These were used to estimate the probability
for each country of protein intake being below the calculated EAR.
We summarize data based on regional classifications from the
reporting regions of the Global Burden of Disease Study 2010 (Lim, et
al., 2012), but we present India and the greater China region
separately because of their large population sizes.
At each stage of analysis, where country-specific data were
unavailable, data were derived from regional estimates, which were in
turn derived from weighted means by population size of each available
country represented within the region (see Table S4 for regions).
Protein-Energy Ratio
Assuming all calories lost from declines in food protein contents
were replaced as carbohydrates (as supported by the stoichiometry of
Loladze 2014), we calculated the ratio of protein to total energy in
current diets and projected diets under eCO2. Because
commodity-based digestibility of energy is less easily estimated,
digestibility was not included in these estimates.
Results
Our analysis was based on 99 high-CO2 experiments and 48
crops, and it included 54 field experiments. Of the 64 experimental
sites, 37 were elsewhere than Europe or North America (see Table S1).
In maize, peas, and mustard seed, we found a linear dose response
when the RR of protein content was compared with the degree of
CO2 elevation above ambient (see Tables S1 and S2).
Metaregression for other crops was not significant, partly because of
insufficient statistical power. Maize protein content under
eCO2 was not significantly below that under aCO2
when considered overall from meta-analyses or when predicted for an
atmospheric CO2 increase of 150 ppm from metaregression.
Metaregression predicted a decrease in pea protein content of 4.1%
(1.6-6.7%) with an atmospheric CO2 increase of 150 ppm, and
overall, meta-analyses showed no significant declines in pea protein.
National changes in dietary protein content were on average 0.04% less
when modeled for a 150 ppm increase in atmospheric CO2 based
on metaregression results compared with meta-analyses. This difference
was small enough to warrant the use of meta-analyses rather than
metaregression. Comparisons between field and pot-based experiments,
and between nitrogen fertilizer treatments were largely nonsignificant
(p>0.05; see Table S2).
Meta-analyses confirmed lower protein content of C3
grains (including barley, 14.1% lower), tubers (including potato, 6.4%
lower), fruit (23.0% lower), and vegetables (17.3% lower) under
eCO2, with no significant change in the protein content of
C4 grains, nitrogen-fixing pulses, or oil crops (Table 1).
When these effect sizes were translated to FBS-standardized
commodity intakes, the mean protein intake decreased under
eCO2 by >5% in 18 countries, including India, Bangladesh,
Turkey, Egypt, Iran, and Iraq. Particularly large declines are expected
through the Middle East and India, where a 5.3% decrease in dietary
protein is predicted (Table 2, Figure 1).
Table 2. Change in dietary protein.
------------------------------------------------------------------------
Mean change in Difference in
Mean change in protein intake protein-energy
Region protein intake (%), plant-based ratio (aCO2
(%) diet minus eCO2, %)
------------------------------------------------------------------------
CALACA ^1.99 (^3.61, ^4.03 (^6.64, ^0.20 (^0.37,
^0.36) ^1.42) ^0.04)
CANAME ^5.04 (^7.29, ^7.87 (^10.88, ^0.52 (^0.75,
^2.79) ^4.85) ^0.29)
CEEAEU ^3.43 (^4.90, ^8.19 (^10.6, ^0.39 (^0.55,
^1.97) ^5.77) ^0.22)
CHINAR ^4.91 (^6.06, ^8.86 (^10.4, ^0.57 (^0.71,
^3.75) ^7.32) ^0.44)
ESEASP ^4.01 (^5.51, ^6.78 (^8.96, ^0.36 (^0.50,
^2.52) ^4.59) ^0.23)
HIGHIN ^2.67 (^3.65, ^7.95 (^9.91, ^0.32 (^0.43,
^1.68) ^5.98) ^0.20)
India ^5.34 (^7.02, ^7.04 (^9.02, ^0.47 (^0.61,
^3.66) ^5.05) ^0.32)
SOASIA ^4.69 (^6.44, ^7.11 (^9.40, ^0.43 (^0.59,
^2.94) ^4.82) ^0.27)
SOTRLA ^2.40 (^3.46, ^6.18 (^8.14, ^0.27 (^0.38,
^1.34) ^4.22) ^0.15)
SUSAAF ^2.03 (^4.05, ^2.71 (^5.13, ^0.18 (^0.36,
^0.01) ^0.30) 0.00)
World ^3.93 (^5.15, ^7.14 (^8.91, ^0.41 (^0.53,
^2.70) ^5.37) ^0.28)
------------------------------------------------------------------------
Note: Figures represent population-weighted averages (and 95% confidence
intervals) globally and for each region (2050 populations). Protein-
energy ratio is the percentage of dietary energy (calories) that is
derived from protein. CALACA, Central and Andean Latin America and the
Caribbean; CANAME, Central Asia, North Africa and the Middle East;
CEEAEU, Central and Eastern Europe; CHINAR, Greater China; ESEASP,
East and Southeast Asia and the Pacific excluding China; HIGHIN, high
income countries; SOASIA, South Asia excluding India; SOTRLA, Southern
and Tropical Latin America; SUSAAF, sub-Saharan Africa. See Table S4
for country grouping.
Figure 1
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Per-country change in dietary protein intake under elevated
carbon dioxide [eCO2 (%)]. Baseline intake is based
on Food and Agriculture Organisation of the United Nations Food
Balance Sheets (FAO FBS) estimates, and changes are calculated
from decreases in protein content in the edible portions of
crops when grown under eCO2. Data were plotted using
the Rworldmap package in R (version 3.2.4; R Development Core
Team).
Globally, >7% decreases in protein intake are predicted for plant-
based diets under eCO2, with countries dependent on
C3 staples particularly affected (Table 2), including
Central Asia, North Africa and the Middle East (7.9%), Central and
Eastern Europe (8.2%), and China (8.9%).A significant positive linear
relationship existed between the natural log of CVprotein
and income-based Gini coefficients (slope 0.026, p<0.0001; Figure 2).
Income inequality explained half of within-country variation in protein
intake (r\2\=0.49).
Figure 2
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Coefficient of variation in protein intake derived from
household surveys plotted against the income-based Gini
coefficient for the year closest to the year household surveys
were conducted (slope 0.026, p<0.0001).
Estimates indicated a 12.2% current risk of protein deficiency
globally. With constant atmospheric CO2 concentrations, we
predict that globally, 15.1% or 1.4 billion people will be at risk of
protein deficiency by 2050 because of demographic changes. This
estimate includes 613.6 million people at risk in sub-Saharan Africa,
276.4 million in India, 131.7 million in Eastern and Southeast Asia and
the Pacific, 84.4 million in Central Latin America and the Caribbean,
and 77.8 million elsewhere in South Asia (Figure 3, Table 3).
Figure 3
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Risk of protein deficiency as defined by protein intake below
estimated average protein requirements (EAR). Estimates of (A)
current percentage of the population at risk of deficiency, (B)
percent of the population newly at risk of deficiency under
elevated carbon dioxide (eCO2), and (C) millions of
people estimated to be newly at risk of deficiency under
eCO2, based on 2050 population projections. Data
were plotted using the Rworldmap package in R (version 3.2.4; R
Development Core Team).
Table 3. Populations at risk of protein deficiency under aCO2 and eCO2 (population-weighted averages and 95%
confidence intervals)
----------------------------------------------------------------------------------------------------------------
At risk of
At risk of Difference in deficiency in
EAR, 2050 protein protein-energy 2050, aCO2 (%)At Additionally at Additionally at
Region (g/d) deficiency, ratio (aCO2 risk of deficiency risk with eCO2: risk with eCO2:
aCO2 (%) minus eCO2, %) in 2050, aCO2 2050 (%) 2050 (millions)
(millions)
----------------------------------------------------------------------------------------------------------------
CALACA 30.49 17.05 (11.64, 18.4 (12.84, 84.37 (58.90, 0.86 (0.57, 3.94 (2.64,
24.65) 25.64) 117.61) 1.19) 5.46)
CANAME 31.46 6.22 (4.00, 7.32 (4.88, 57.2 (38.09, 1.53 (1.14, 11.97 (8.93,
9.32) 10.46) 81.71) 1.94) 15.12)
CEEAEU 33.44 3.58 (1.40, 3.52 (1.37, 9.64 (3.74, 26.77) 0.56 (0.27, 1.52 (0.73,
9.84) 9.79) 0.95) 2.61)
CHINAR 31.68 5.25 (0.16, 5.38 (0.16, 74.96 (2.27, 297) 1.14 (0.11, 15.94 (1.47,
21.01) 21.31) 2.04) 28.45)
ESEASP 29.47 15.35 (9.59, 15.79 (9.68, 131.67 (80.71, 1.92 (1.40, 15.99 (11.68,
22.78) 23.56) 196.44) 2.43) 20.28)
HIGHIN 33.05 2.62 (1.01, 2.6 (0.99, 28.39 (10.83, 0.31 (0.16, 3.41 (1.75,
6.86) 7.36) 80.47) 0.53) 5.78)
India 30.06 16.27 (3.73, 17.06 (4.46, 276.42 (72.32, 3.30 (1.93, 53.41 (31.22,
32.49) 33.36) 540.41) 4.55) 73.71)
SOASIA 30.41 13.23 (6.15, 13.74 (6.91, 77.76 (39.10, 2.80 (1.88, 15.86 (10.64,
21.98) 22.59) 127.88) 3.74) 21.20)
SOTRLA 31.35 11.46 (2.80, 12.03 (3.25, 38.14 (10.30, 0.68 (0.26, 2.17 (0.81,
27.14) 27.40) 86.87) 1.07) 3.39)
SUSAAF 30.53 27.12 (23.07, 28.89 (24.73, 613.56 (525.07, 1.16 (0.73, 24.64 (15.44,
31.46) 33.44) 710.24) 1.59) 33.83)
World 30.99 12.18 (9.07, 15.06 (12.11, 1424.59 (1145.89, 1.57 (1.26, 148.37 (119.06,
16.32) 18.71) 1770.20) 1.86) 176.09)
----------------------------------------------------------------------------------------------------------------
Note: Calculations use 2011 populations and 2050 population projections. aCO2, ambient atmospheric carbon
dioxide; CALACA, Central and Andean Latin America and the Caribbean; CANAME, Central Asia, North Africa and
the Middle East; CEEAEU, Central and Eastern Europe; CHINAR, Greater China; EAR, estimated average protein
requirement based on 2050 demographic projections; eCO2 elevated atmospheric carbon dioxide; ESEASP, East and
Southeast Asia and the Pacific excluding China; HIGHIN, high income countries; SOASIA, South Asia excluding
India; SOTRLA, Southern and Tropical Latin America; SUSAAF, sub-Saharan Africa. See Table S4 for country
grouping.
With predicted atmospheric CO2 concentrations >500ppm by
2050, we estimate an additional 1.57% of the world's population (148.4
million) will be at risk of protein deficiency, compared with 2050
aCO2 scenarios. In particular, an additional 53.4 million
people in India, 15.9 million elsewhere in South Asia and 24.6 million
in sub-Saharan Africa are estimated to become newly at risk (Table 3,
Figure 3). An additional 15.9 million people in the China region and
12.0 million in Central Asia, North Africa, and the Middle East are
expected to become at risk with eCO2. The greatest increases
in percent at risk of protein deficiency are expected in Tajikistan,
Bangladesh, Burundi, Liberia, Occupied Palestinian Territory, Iraq, and
Afghanistan (Figure 3B).
Globally, we predict the protein-energy ratio (protein caloric
contribution as a percent of total calories) to decrease under
eCO2 by 0.41%; in individual countries and regions, we
predict this ratio to decrease by 0.6% in 17 counties including China,
Iran, Iraq, Morocco, and Turkey. We expect decreases in China of 0.57%
(Table 2).
Discussion
Our study highlights the potential impact of eCO2 on
dietary protein intake globally. Wheat and rice, among the most
sensitive crops to eCO2, are primary protein sources for 71%
of the world's population (FAO 2014a). By 2050, 148.4 million people
worldwide may become at risk of protein deficiency from rising
CO2. In India, expected to be the world's most populous
country (UN 2013), and a country that is highly dependent on rice, 53.4
million people may be newly at risk of protein deficiency.
Additionally, the protein deficiency in roughly 1.4 billion people
globally (predicted under aCO2 in 2050) is anticipated to
become more severe under eCO2 scenarios. Although estimates
of current protein intake and income inequality highlight the current
risk of deficiency in sub-Saharan Africa and South America, their
dependence on less-sensitive C4 crops make these diets less
sensitive to eCO2.
Importantly, we incorporated into the risk assessment different
distributions of protein intake in countries based on income inequality
from the association of income-based Gini coefficients with variability
in protein intake from national dietary surveys. We find it equally
plausible that CVprotein would decrease or increase by 2050.
We therefore provide the most conservative estimate of future protein
intake distributions, namely that CVprotein within countries
will remain unchanged. We also assume unchanged duration and prevalence
of breastfeeding, and unchanged adult height.
Although our calculations assume no change in the shape of the
intake distribution, we anticipate a worsening of inequality in protein
intake within populations because a larger decrease in protein content
is observed in plant-based than in omnivore diets under eCO2
(Table 2). Some changes in meat quality are anticipated owing to
increased fat content under lower-protein diets (Blome, et al., 2003),
but this is likely to be negligible compared with the effects on plant-
based protein sources. Those who consume the least protein have diets
more dependent on plant protein, and these people are more vulnerable
to eCO2 effects on plant protein. This is likely to extend
the lower tail of the intake distribution, increasing the severity and
prevalence of protein inadequacy. Our estimates are worst-case
scenarios where no substitution of animal-sourced protein sources for
other high-protein foods is allowed. In particular, the predicted large
decreases in protein content of plant-based diets in high income
countries may be overestimates, where plant-based diets are likely to
be supplemented with other protein sources.
The countries that we estimated to be currently most at risk of
protein deficiency are also those with the greatest estimated
prevalence of undernourishment (FAO 2014b), increasing confidence in
our estimates; however, energy balance and nitrogen balance interact
(Garza, et al., 1976). For simplicity, we modeled overall protein
intake and risk of deficiency based on the EAR, which assumes adequate
energy intake. Published EARs are defined for zero protein balance,
which is a conservative estimate of protein requirements (IOM 2005).
Older, sedentary people and those suffering from or recovering from
illness are likely to be at greater risk of deficiency in any
population (Ghosh 2013). We have not accounted for current or future
patterns of illness in our estimates of EAR. Furthermore, we have not
considered changes in protein quality; however, several studies have
shown that essential amino acids tend to be relatively preserved at the
expense of nonessential amino acids under eCO2, and
degradability may decrease (Hogy, et al,. 2009; Wroblewitz, et al.,
2013). Bioavailability may change, for example, if meal composition and
thus digestibility changes. Furthermore, levels of secondary
metabolites, including toxins, tend to increase under elevated
CO2 (Cavagnaro, et al., 2011), which could decrease protein
bioavailability.
In addition to increasing the risk of protein deficiency, there may
be other nutritional consequences of changing the stoichiometry of
carbohydrate-to-protein ratios in staple food crops. For example,
replacing dietary carbohydrate with protein has been shown in
interventional trials and observational studies to 15-y duration, and
in diverse countries including Japan, China, the United States, and
Chile, to improve cardiovascular disease risk through lowering blood
pressure and changing lipid profiles (Hu, et al., 1999; Obarzanek, et
al., 1996; Appel, et al., 2005; Altorf-van der Kuil, et al., 2010;
Rebholz, et al., 2012). Improvements are often greatest with plant--
rather than animal-sourced protein (Altorf-van der Kuil, et al., 2010).
These experiments underscore the need for additional investigation into
whether replacing plant-sourced protein with plant-sourced carbohydrate
could exacerbate the already concerning pandemic of metabolic disease
driving increased cardiovascular morbidity and mortality globally.
It is unclear how trends in dietary quality will be counterbalanced
by the effects of population growth and climate change. That is why,
for our analysis, we assume no future change to food composition of
diets or to per capita food intake and no dietary substitution to
compensate for deficits. Agricultural production will need to roughly
double to match increasing demand by 2050 (Alexandratos 1999). Climate
change may pose the greatest challenge to this need. Climate change-
induced reductions in crop yield are expected to be greatest in lower-
latitude regions, including developing countries and those dependent on
C4 crops (Rosenzweig, et al., 2014). Resulting economic
changes may shape future diets, and changes to water, soils, and
weather in these areas may affect crops in ways that may overwhelm, or
exacerbate, the effects of eCO2. For example, decreases in
yield under drought and warming temperatures may counteract the effects
of rising CO2 on protein concentrations (Kimball, et al.,
2001). Only 37 of 99 study sites in our meta-analysis were in countries
outside of Europe and North America, and only just over half of the
studies were performed in the field, with only 10% involving watering
experiments (see Table S1). Most experiments were undertaken over 1 y
only, and effects on crop nutrient content may not match those under
the next 50 y of gradual atmospheric CO2 increase. The
consistent decreases in protein contents across C3 crop
cultivars, including 47 wheat cultivars and 27 rice cultivars, reassure
us that our results are generalizable to other cultivars. Nevertheless,
to better predict the dietary impacts of eCO2, we need more
long-term field-based eCO2 experiments involving plants and
cultivars grown under the climates and farming practices applicable to
the developing world.
We also assumed that global population growth and future
demographic trends will match UN projections, which include declining
fertility rates, and migration from developing to developed countries
(UN 2013). However, the greatest population growth is projected to
occur in areas most vulnerable to climate change (Watts, et al., 2015).
Climate, economic, and demographic changes will likely interact,
producing a global population distribution that we are not yet able to
fully comprehend. In the absence of conclusive projections of future
food production, we believe it is the most conservative, albeit perhaps
optimistic, assumption that per capita food intake will remain constant
despite sharp increases in global demand.
In predicting the nutritional consequences of eCO2,
other nutrients must be considered. Zinc and iron concentrations are
greatly decreased in C3 plants grown under eCO2
(Myers, et al., 2014). Zinc is a cofactor for protein synthesis, and
protein inadequacy decreases uptake and availability of other nutrients
(Gropper and Smith 2008). A recent analysis predicts strong increases
in the risk of global zinc deficiency with eCO2 (Myers, et
al., 2015). Identifying the countries most vulnerable to future
malnutrition requires a targeted synthesis of crop research on climate
and CO2 responses. This information can then be applied to
global climate and atmospheric models.
To our knowledge, this is the first global comparison of dietary
protein that estimates a country-specific CV. Like energy consumption,
the variability of protein consumption in a population relates to the
Gini coefficient (Raubenheimer, et al., 2015). Our use of this metric
would be expected to produce more accurate estimates than the
previously used 25% CV (Ghosh 2013). The WHO continues to refine its
models of energy intake variability based on gross domestic product
(GDP), Gini, and food prices, using skew log rather than lognormal
distributions. As this methodology becomes available, future work could
incorporate these considerations to produce better estimates of protein
consumption.
Because added fertilizer did not predictably mitigate the effects
of CO2 on crop protein, and with the production and
application of fertilizer being a principal contributor to agricultural
greenhouse gas emissions (Vermeulen, et al., 2012), we cannot simply
add more fertilizer to reduce the protein deficit. As populations
increase, and with livestock production being resource-intensive
(Vermeulen, et al., 2012), eating more meat is not a practical
solution. Cultivars could be selected or bred based on their
nutritional content under eCO2. In addition to efforts to
mitigate CO2 emissions, nutritious and resilient crops
should be promoted, for example legumes, which will withstand the
effects of eCO2 on protein content. Because eCO2
may have the greatest effect on the protein intake of those with the
poorest diets, more equitable food distribution, and poverty reduction
measures should be a focus for minimizing risk of deficiency.
Conclusions
Anthropogenic CO2 emissions, via their impact on the
protein content of C3 staples, may threaten the adequacy of
protein intake for many populations. Although quantifying protein
deficiency is notoriously difficult, we have estimated current and
future risk of protein deficiency by country and region, suggesting
enduring challenges for sub-Saharan Africa and growing challenges for
South Asia, including India. For nutritionally sensitive agriculture,
the high CO2 effects on crop nutrient contents must be
incorporated into future food security policies.
Acknowledgments
We thank A. Fangmeier for additional data generously shared, M.
Smith for valuable comments and data, M. Stefan and R. Wessells for
statistical advice, W. Willett for help with project conception, the
Harvard University Center for the Environment for hosting D.E.M., and
C. Hotz for her insights into the literature on protein deficiency.
Financial support was provided by the Bill & Melinda Gates
Foundation and by the Winslow Foundation. Funding sources had no input
into study design, data collection, analysis, data interpretation,
report writing, or decision to submit the manuscript for publication.
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Article 2
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]
[https://fireecology.springeropen.com/articles/10.1186/s42408-019-0062-
8]
Fire Ecology
Changing wildfire, changing forests: the effects of climate change on
fire regimes and vegetation in the Pacific Northwest, USA
Jessica E. Halofsky * \1\, David L. Peterson \2\ and Brian J. Harvey
\2\
---------------------------------------------------------------------------
* Correspondence: [email protected].
\1\ U.S. Department of Agriculture, Forest Service, Pacific
Northwest Research Station, Olympia Forestry Sciences Lab, 3625 93rd
Avenue SW, Olympia, Washington 98512, USA.
\2\ School of Environmental and Forest Sciences, College of the
Environment, University of Washington, Box 352100, Seattle, Washington
98195-2100, USA.
The Author(s). 2020 Open Access This
article is licensed under a Creative Commons Attribution 4.0
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by/4.0/.
Full list of author information is available at the end of the
article.
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Abstract
Background: Wildfires in the Pacific Northwest (Washington, Oregon,
Idaho, and western Montana, USA) have been immense in recent years,
capturing the attention of resource managers, fire scientists, and the
general public. This paper synthesizes understanding of the potential
effects of changing climate and fire regimes on Pacific Northwest
forests, including effects on disturbance and stress interactions,
forest structure and composition, and post-fire ecological processes.
We frame this information in a risk assessment context, and conclude
with management implications and future research needs.
Results: Large and severe fires in the Pacific Northwest are
associated with warm and dry conditions, and such conditions will
likely occur with increasing frequency in a warming climate. According
to projections based on historical records, current trends, and
simulation modeling, protracted warmer and drier conditions will drive
lower fuel moisture and longer fire seasons in the future, likely
increasing the frequency and extent of fires compared to the twentieth
century. Interactions between fire and other disturbances, such as
drought and insect outbreaks, are likely to be the primary drivers of
ecosystem change in a warming climate. Reburns are also likely to occur
more frequently with warming and drought, with potential effects on
tree regeneration and species composition. Hotter, drier sites may be
particularly at risk for regeneration failures.
Conclusion: Resource managers will likely be unable to affect the
total area burned by fire, as this trend is driven strongly by climate.
However, fuel treatments, when implemented in a spatially strategic
manner, can help to decrease fire intensity and severity and improve
forest resilience to fire, insects, and drought. Where fuel treatments
are less effective (wetter, high-elevation, and coastal forests),
managers may consider implementing fuel breaks around high-value
resources. When and where post-fire planting is an option, planting
different genetic stock than has been used in the past may increase
seedling survival. Planting seedlings on cooler, wetter microsites may
also help to increase survival. In the driest topographic locations,
managers may need to consider where they will try to forestall change
and where they will allow conversions to vegetation other than what is
currently dominant.
Keywords: adaptation, climate change, disturbance regimes, drought,
fire regime, Pacific Northwest, regeneration, vegetation.
Resumen
Antecedentes: Los incendios de vegetacion en el Noroeste del
pacifico (Washington, Oregon, Idaho, y el oeste de Montana, EEUU), han
sido inmensos en anos recientes, capturando la atencion de los gestores
de recursos, de cientificos dedicados a los incendios, y del publico en
general. Este trabajo sintetiza el conocimiento de los efectos
potenciales del cambio climatico y de los regimenes de fuego en bosques
del noroeste del Pacifico, incluyendo los efectos sobre las
interacciones entre disturbios y distintos estreses, la estructura y
composicion de los bosques, y los procesos ecologicos posteriores.
Encuadramos esta informacion en el contexto de la determinacion del
riesgo, y concluimos con implicancias en el manejo y la necesidad de
futuras investigaciones.
Resultados: Los incendios grandes y severos en el Noroeste del
Pacifico estan asociados con condiciones calurosas y secas, y tales
condiciones muy probablemente ocurran con el incremento en la
frecuencia del calentamiento global. De acuerdo a proyecciones basadas
en registros historicos, tendencias actuales y modelos de simulacion,
condiciones prolongadas de aumento de temperaturas y sequias conduciran
a menores niveles de humedad, incrementando probablemente la frecuencia
y extension de fuegos en el futuro, en comparacion con lo ocurrido
durante el siglo XX. Las interacciones entre el fuego y otros
disturbios, son probablemente los principales conductores de cambios en
los ecosistemas en el marco del calentamiento global. Los incendios
recurrentes podrian ocurrir mas frecuentemente con aumentos de
temperatura y sequias, con efectos potenciales en la regeneracion de
especies forestales y en la composicion de especies. Los sitios mas
calidos y secos, pueden estar particularmente en riesgo por fallas en
la regeneracion.
Conclusiones: Los gestores de recursos no podrian tener ningun
efecto sobre el area quemada, ya que esta tendencia esta fuertemente
influenciada por el clima. Sin embargo, el tratamiento de combustibles,
cuando esta implementado de una manera espacialmente estrategica, puede
ayudar a reducir la intensidad y severidad de los incendios, y mejorar
la resiliencia de los bosques al fuego, insectos, y sequias. En lugares
en los que el tratamiento de combustibles es menos efectivo (areas mas
humedas, elevadas, y bosques costeros) los gestores deberian considerar
implementar barreras de combustible alrededor de valores a proteger.
Cuando y donde la plantacion post fuego sea una opcion, plantulas
provenientes de diferentes stocks geneticos de aquellos que han sido
usados en el pasado pueden incrementar su supervivencia. La plantacion
de plantulas en micrositios mas humedos y frios podria ayudar tambien a
incrementar la supervivencia de plantulas. En ubicaciones topograaficas
mas secas, los gestores deberian considerar evitar cambios y donde
estos sean posibles, permitir conversiones a tipos de vegetacion
diferentes a las actualmente dominantes.
Abbreviations
ENSO: El Nino-Southern Oscillation
MPB: Mountain Pine Beetle
PDO: Pacific Decadal Oscillation
Introduction
Large fires are becoming a near-annual occurrence in many regions
globally as fire regimes are changing with warming temperatures and
shifting precipitation patterns. The U.S. Pacific Northwest (states of
Washington, Oregon, Idaho, and western Montana, USA; hereafter the
Northwest) is no exception. In 2014, the largest wildfire in recorded
history for Washington State occurred, the 103 640 ha Carlton Complex
Fire (Fig. 1). In 2015, an extreme drought year with very low snowpack
across the Northwest (Marlier, et al., 2017), 688 000 ha burned in
Oregon and Washington (Fig. 2), with over 3.6 million ha burned in the
western United States. Several fires in 2015 occurred in conifer
forests on the west (i.e., wet) side of the Cascade Range, including a
rare fire event in coastal temperate rainforest on the Olympic
Peninsula. In some locations, short-interval reburns have occurred. For
example, one location on Mount Adams in southwestern Washington burned
three times between 2008 and 2015 (Fig. 3). Similarly, during the
summer of 2017 in southwestern Oregon, the 77 000 ha Chetco Bar Fire
burned over 40 000 ha of the 2002 Biscuit Fire, including a portion of
the Biscuit Fire that had burned over part of the 1987 Silver Fire. At
over 200 000 ha, the Biscuit Fire was the largest fire in the recorded
history of Oregon.
Fig. 1
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Large wildfires, such as the 2014 Carlton Complex Fire in
Washington, USA (103 640 ha), have occurred throughout western
North America during the past several decades. These
disturbances have a significant effect on landscape pattern and
forest structure and will likely become more common in a warmer
climate, especially in forests with heavy fuel loadings. Photo
credit: Morris Johnson.
Fig. 2
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Fires burning across the Pacific Northwest, USA, on 25 August
2015. This natural-color satellite image was collected by the
Moderate Resolution Imaging Spectroradiometer (MODIS) aboard
the Aqua satellite. Actively burning areas, detected by MODIS's
thermal bands, are outlined in red. National Aeronautics and
Space Administration image courtesy of Jeff Schmaltz, MODIS
Rapid Response Team.
Fig. 3a
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Fig. 3b
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
(a) Large fires around Mount Adams in Gifford Pinchot
National Forest in southwestern Washington, USA, between 2001
and 2015 (area in orange burned twice, and area in red burned
three times); and (b) area in Gifford Pinchot National Forest
that has burned three times since 2008 (2008 Cold Springs fire,
2012 Cascade Creek fire, and 2015 Cougar Creek fire). Map
credit: Robert Norheim; photo credit: Darryl Lloyd.
Over the twentieth century in the Northwest, years with relatively
warm and dry conditions have generally corresponded with larger fires
and greater area burned (Trouet, et al., 2006; Westerling, et al.,
2006; Littell, et al., 2009; Littell, et al., 2010; Abatzoglou and
Kolden 2013; Cansler and McKenzie 2014; Dennison, et al., 2014;
Stavros, et al., 2014; Westerling 2016; Kitzberger, et al., 2017;
Reilly, et al., 2017; Holden, et al., 2018). Decreasing fuel moisture
and increasing duration of warm, dry weather creates large areas of dry
fuels that are more likely to ignite and carry fire over a longer
period of time (Littell, et al., 2009).
A warming climate will have profound effects on fire frequency,
extent, and possibly severity in the Northwest. Increased temperatures
are projected to lengthen fire and growing seasons, increase
evaporative demand, decrease soil and fuel moisture, increase
likelihood of large fires, and increase area burned by wildfire
(McKenzie, et al., 2004; Littell, et al., 2010; Stavros, et al., 2014;
Westerling 2016). Decreased summer precipitation is also projected to
increase area burned (Holden, et al., 2018).
Interactions between fire and other disturbance agents (e.g.,
drought, insect outbreaks) will likely catalyze ecosystem changes in a
warming climate. Increased tree stress and interacting effects of
drought may also contribute to increasing wildfire severity (damage to
vegetation and soils) and area burned (McKenzie, et al., 2009; Stavros,
et al., 2014; Littell, et al., 2016; Reilly, et al., 2017).
Climatic changes and associated stressors can interact with altered
vegetation conditions (e.g., those resulting from historical management
practices) to affect fire frequency, extent, and severity, as well as
forest conditions in the future (Keeley and Syphard 2016). Human
influence through domestic livestock grazing, road construction,
conversion of land to agriculture, and urbanization has resulted in
(direct or indirect) exclusion of fires in dry forests (Hessburg, et
al., 2005). Many larger, fire-resistant trees have been removed by
selective logging. These activities, along with active fire
suppression, have resulted in increased forest density and fuel buildup
in forests historically characterized by frequent, low-severity and
mixed-severity fires (Hessburg, et al., 2005). Although landscape
pattern and fuel limitations were key factors that limited fire size
and severity historically, these limitations have been largely removed
from many contemporary landscapes, thus increasing the potential for
large high-severity fires, particularly in a warming climate.
Facing such changes, land managers need information on the
magnitude and likelihood of altered fire regimes and forest conditions
in a warming climate to help guide long-term sustainable resource
management. Many published studies have explored the potential effects
of climate change on forest fire in the Northwest, including
paleoecological, modeling, and local- to regional-scale empirical
studies. However, to our knowledge, there is no single resource that
synthesizes these varied studies for the Northwest region. A synthesis
of this information can help managers better understand the potential
effects of climate change on ecosystem processes, assess risks, and
implement actions to reduce the negative effects of climate change and
transition systems to new conditions.
In this synthesis, we draw from relevant published literature to
discuss potential effects of changing climate on fire frequency,
extent, and severity in Northwest forests. Sources of information
include: (1) long-term (centuries to millennia) paleoecological studies
of climate, fire, and species distribution; (2) medium-term (decades to
centuries) fire history studies; (3) near-term (years to decades)
studies on trends in vegetation and fire associated with recent
climatic variability and change; (4) forward-looking studies using
simulation models to project future fire and vegetation change; and (5)
recent syntheses focused on potential climate change effects.
We used regionally specific information where possible, including
information from adjacent regions with forests of similar structure and
function when relevant. Following an overview of climate projections,
we (1) identified risks related to wildfire as affected by climate
change in three broad ecosystem types; (2) explored the magnitude and
likelihood of those risks; and (3) concluded with a discussion of
uncertainties about future climate and fire, potential future research,
and implications for resource management.
Overview of climate projections
Warming temperatures and changing precipitation patterns will
affect amount, timing, and type of precipitation; snowmelt timing and
rate (Luce, et al., 2012; Luce, et al., 2013; Safeeq, et al., 2013);
streamflow magnitude (Hidalgo, et al., 2009; Mantua, et al., 2010); and
soil moisture content (McKenzie and Littell 2017). Compared to the
historical period from 1976 to 2005, 32 global climate models project
increases in mean annual temperature for the middle and end of the
twenty-first century in the Northwest. These projected increases range
from 2.0 to 2.6 C for mid-century (2036 to 2065) and 2.8 to 4.7 C for
the end of the century (2071 to 2100), depending on future greenhouse
gas emissions (specifically representative concentration pathway 4.5 or
8.5; Vose, et al., 2017). Warming is expected to occur during all
seasons, although most models project the largest temperature increases
in summer (Mote, et al., 2014). All models suggest a future increase in
heat extremes (Vose, et al., 2017).
Changes in precipitation are less certain than those for
temperature. Global climate model projections for annual average
precipitation range from ^4.7 to +13.5%, averaging about +3% among
models (Mote, et al., 2014). A majority of models project decreases in
summer precipitation, but projections for precipitation vary for other
seasons. However, models agree that extreme precipitation events (i.e.,
number of days with precipitation >2.5 cm) will likely increase, and
that the length of time between precipitation events will increase
(Mote, et al., 2014; Easterling, et al., 2017).
Risk assessment
A risk-based approach to climate change vulnerability assessments
provides a common framework to evaluate potential climate change
effects and identify a structured way to choose among adaptation
actions or actions to mitigate climate change risks (EPA 2014). Risk
assessment is linked with risk management by (1) identifying risks--
that is, how climate change may prevent an agency or other entity from
reaching its goals; (2) analyzing the potential magnitude of
consequences and likelihood for each risk; (3) selecting a set of risk-
reducing actions to implement; and (4) prioritizing those actions that
address risks with the highest likelihood and magnitude of consequences
(EPA 2014).
Here, we summarized potential risks that are relevant for natural
resource management associated with climate-fire interactions,
including: wildfire frequency, extent, and severity; reburns; stress
interactions; and regeneration for (1) moist coniferous forest (low to
mid elevation), (2) dry coniferous forest and woodland (low to mid
elevation), and (3) subalpine coniferous forest and woodland (high
elevation). The likelihood and magnitude of consequences, and
confidence in inferences are described for each risk. Although the
information provided here does not constitute risk management, as
described in the previous paragraph, this information can be used to
inform more site- and resource-specific risk assessments and risk
management.
The risks identified here were inferred from the authors' review of
the published literature described below, as well as experience with
developing climate change vulnerability assessments in the study region
over the past decade (Halofsky, et al., 2011a, b; Raymond, et al.,
2014; Halofsky and Peterson 2017a, b; Halofsky, et al., 2019; Hudec, et
al., 2019). These assessments encompassed all ecosystems and species
addressed in this synthesis, and included extensive discussion of the
effects of wildfire and other disturbances. Climate change effects and
adaptation options in the assessments were greatly informed by input
from resource managers as well as by scientific information. Thus, many
fire-related vulnerabilities identified in the assessments are relevant
to the risk assessment discussed here.
Risk in moist coniferous forests
Most climate-fire risks in moist coniferous forests are relatively
low (Table 1). These forests occur west of the Cascade Range in Oregon
and Washington and are frequently dominated by Douglas-fir
(Pseudotstuga menziesii [Mirb.] Franco) and western hemlock (Tsuga
heterophylla [Raf.] Sarg.). Moist coniferous forests are characterized
by an infrequent, stand-replacing (i.e., high-severity) fire regime
(Agee 1993). Although fire frequency and severity may increase with
climate change, the frequency of fire in these moist ecosystems will
likely remain relatively low.
Table 1
Risk assessment for the effects of fire-climate interactions in moist
coniferous forest, low to mid elevation (Olympics, west-side Cascades,
northern Idaho, west-side Rocky Mountains, USA), for the mid to late
twenty-first century. Likelihood and confidence are rated low, moderate,
and high. Low likelihood represents consequences that are unlikely
(approximately 0 to 33% probability), moderate likelihood represents
consequences that are about as likely as not (approximately 33 to 66%
probability), high likelihood represents consequences that are likely to
very likely (approximately 66 to 100% probability). Low confidence is
characterized by low scientific agreement and limited evidence, whereas
high confidence is characterized by high scientific agreement and robust
evidence, with moderate confidence falling between those two extremes
-------------------------------------------------------------------------
Fire-climate Magnitude of Likelihood of
interaction consequences consequences Confidence
------------------------------------------------------------------------
Wildfire Small increase Low High
frequency
Wildfire extent Small increase Low Moderate
Wildfire severity No change to Low Moderate
small increase
Reburns No change to Low Moderate
small increase
Stress Small increase Low to moderate Moderate
interactions
Regeneration No change to Low Low
small decrease
------------------------------------------------------------------------
Risk in dry coniferous forests
Climate-fire risks in dry coniferous forests and woodlands are high
for increased fire frequency, extent, and severity (Table 2). Dry
coniferous forests and woodlands occur at lower elevations in
southwestern Oregon, east of the Cascade Range in Oregon and
Washington, and at lower elevations in the Rocky Mountains in Idaho and
Montana. Fire regimes in these forests and woodlands range from
moderate frequency and mixed severity to frequent and low severity.
Ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) is a
characteristic species, along with Douglas-fir, grand fir (Abies
grandis [Douglas ex D. Don] Lindl.), and white fir (Abies concolor
[Gordon & Glend.] Lindl. ex Hildebr.). These forests and woodlands are
also at risk from interacting disturbances and hydrologic change
(moderate to high likelihood and magnitude of consequences), and post-
fire regeneration failures are likely to occur on some sites.
Table 2
Risk assessment for the effects of fire-climate interactions in dry
coniferous forest and woodlands, low to mid elevation (east-side
Cascades, southern Idaho, drier areas of Rocky Mountains, USA), for the
mid to late twenty-first century. Likelihood and confidence are rated
low, moderate, and high. Low likelihood represents consequences that are
unlikely (approximately 0 to 33% probability), moderate likelihood
represents consequences that are about as likely as not (approximately
33 to 66% probability), high likelihood represents consequences that are
likely to very likely (approximately 66 to 100% probability). Low
confidence is characterized by low scientific agreement and limited
evidence, whereas high confidence is characterized by high scientific
agreement and robust evidence, with moderate confidence falling between
those two extremes
-------------------------------------------------------------------------
Fire-climate Magnitude of Likelihood of
interaction consequences consequences Confidence
------------------------------------------------------------------------
Wildfire Large increase High High
frequency
Wildfire extent Large increase High High
Wildfire severity Large increase in High High
areas with
elevated fuel
loading
Reburns Moderate increase Moderate Moderate
Stress Large increase High High
interactions
Regeneration Low to high Moderate Moderate
decrease,
depending on
site
------------------------------------------------------------------------
Risk in high-elevation forests
Climate-fire risks in high-elevation forests are moderate, with a
primary factor being increased fire frequency and extent in lower-
elevation forests spreading to higher-elevation systems (Table 3).
Regeneration could be challenging in locations where seed availability
is low due to very large fires. High-elevation forests occur in
mountainous areas across the Northwest. They are characterized by
species such as subalpine fir (Abies lasiocarpa [Hook.] Nutt.),
mountain hemlock (Tsuga mertensiana [Bong.] Carriere), and lodgepole
pine (Pinus contorta var. contorta Engelm. ex S. Watson). High-
elevation forests are characterized by infrequent, stand-replacement
fire regimes (Agee 1993). Risks of stress interactions are also
moderate, because drought and insect outbreaks will likely affect high-
elevation forests with increasing frequency.
Table 3
Risk assessment for the effects of fire-climate interactions in
subalpine coniferous forest and woodland, high elevation (including
aspen; all U.S. Pacific Northwest mountain ranges), for the mid to late
twenty-first century. Likelihood and confidence are rated low, moderate,
and high. Low likelihood represents consequences that are unlikely
(approximately 0 to 33% probability), moderate likelihood represents
consequences that are about as likely as not (approximately 33 to 66%
probability), high likelihood represents consequences that are likely to
very likely (approximately 66 to 100% probability). Low confidence is
characterized by low scientific agreement and limited evidence, whereas
high confidence is characterized by high scientific agreement and robust
evidence, with moderate confidence falling between those two extremes
-------------------------------------------------------------------------
Fire-climate Magnitude of Likelihood of
interaction consequences consequences Confidence
------------------------------------------------------------------------
Wildfire Moderate increase Moderate High
frequency
Wildfire extent Moderate increase Moderate Moderate
Wildfire severity No change to Low Moderate
small increase
Reburns No change to Low Moderate
small increase
Stress Small increase Moderate Moderate
interactions
Regeneration Variable, Moderate Moderate
depending on
fire size
------------------------------------------------------------------------
Historical and contemporary fire-climate relationships
Paleoclimate and fire data
Wildfire-derived charcoal deposited in lake sediments can be used
to identify individual fire events and to estimate fire frequency over
hundreds to thousands of years (Itter, et al., 2017). In combination
with sediment pollen records, charcoal records help to determine how
vegetation and fire frequency and severity shifted with climatic
variability in the past (Gavin, et al., 2007). Existing paleoecological
reconstructions of the Northwest are based mostly on pollen and
charcoal records from lakes in forested areas west of the Cascade
Range, with few studies in the dry interior of the region (Kerns, et
al., 2017).
The early Holocene (circa 10 500 to 5,000 years BP) was the warmest
post-glacial period in the Northwest (Whitlock 1992). During the early
Holocene, summers were warmer and drier relative to recent historical
conditions, with more intense droughts (Whitlock 1992; Briles, et al.,
2005). In many parts of the Northwest, these warmer and drier summer
conditions were associated with higher fire frequency (Whitlock 1992;
Walsh, et al., 2008; Walsh, et al., 2015).
Sediment charcoal analysis documented relatively frequent (across
the paleoecological record) fire activity during the early Holocene in
eight locations: North Cascade Range (Prichard, et al., 2009), Olympic
Peninsula (Gavin, et al., 2013), Puget Lowlands (Crausbay, et al.,
2017), southwestern Washington (Walsh, et al., 2008), Oregon Coast
Range (Long, et al., 1998), Willamette Valley (Walsh, et al., 2010),
Siskiyou Mountains (Briles, et al., 2005), and Northern Rocky Mountains
in Idaho (Brunelle and Whitlock 2003) (Table 4). Higher fire frequency
in these locations was generally associated with higher abundance of
tree species adapted to survive fire or regenerate soon after fire,
including Douglas-fir, lodgepole pine, and Oregon white oak (Quercus
garryana Douglas ex Hook.) (Table 4). Other pollen analyses (without
parallel charcoal analysis) support the expansion of these species
during the early Holocene (e.g., Sea and Whitlock 1995; Worona and
Whitlock 1995), in addition to the expansion of ponderosa pine and oak
in drier interior forests (Hansen 1943; Whitlock and Bartlein 1997).
Relatively frequent fire (across the paleoecological record) during the
early Holocene likely resulted in a mosaic of forest successional
stages, with species such as red alder (Alnus rubra Bong.) dominating
early-successional stages in mesic forest types (Cwynar 1987).
Table 4
Dominant tree species (current [late twentieth to early twenty-first
century] and during the Early Holocene, circa 10 500 to 5,000 yr BP) in
select locations in the Pacific Northwest, USA, where charcoal analysis
indicated increased fire activity in the warmer and drier summers of the
Early Holocene. Locations are listed from north to south. These studies
were selected to cover a range of geographic locations and forest types
and do not represent a comprehensive list of charcoal analyses for the
Northwest. For a more comprehensive list, see Walsh, et al. (2015)
-------------------------------------------------------------------------
Early
Current Holocene
Region Elevation Latitude, dominant dominant Reference
(site) (m) longitude () tree tree
species a species a
------------------------------------------------------------------------
North 1100 48.658, ^121.04 Douglas- Lodgepole Prichard,
Cascad fir, pine et al.,
e Pacific 2009
Range, silver
Washin fir,
gton western
(Panth hemlock,
er western
Pothol redcedar
es)
Puget 430 47.772, ^121.811 Douglas- Douglas- Crausbay,
Lowlan fir, fir et al.,
ds, western 2017
Washin hemlock,
gton western
(Marck redcedar
worth
State
Forest
)
Western 710 47.677, ^124.018 Pacific Douglas- Gavin, et
Olympi silver fir, red al.,
c fir, alder, 2013
Penins western Sitka
ula, hemlock, spruce
Washin western
gton redcedar
(Yahoo
Lake)
Southwe 154 45.805, ^122.494 Douglas- Oregon Walsh, et
stern fir, white al.,
Washin western oak, 2008
gton redcedar Douglas-
(Battl , fir
e western
Ground hemlock,
Lake) grand
fir,
Sitka
spruce
Norther 2250 45.704, ^114.987 Subalpine Douglas- Brunelle
n fir, fir, and
Rocky whitebar whitebar Whitlock
Mounta k pine, k pine, 2003
ins, lodgepol lodgepol
Idaho e pine, e pine
(Burnt Engelman
Knob n spruce
Lake)
Willame 69 44.551, ^123.17 Willow, Oregon Walsh, et
tte black white al.,
Valley cottonwo oak, 2010
, od, Douglas-
Oregon Oregon fir,
(Beave ash, beaked
r Oregon hazel,
Lake) white bigleaf
oak maple,
red
alder
Oregon 210 44.167, ^123.584 Western Douglas- Long, et
Coast hemlock, fir, red al.,
Range Douglas- alder, 1998
(Littl fir, Oregon
e western white
Lake) redcedar oak
, grand
fir,
Sitka
spruce
Siskiyo 1600 42.022, ^123.459 White Western Briles,
u fir, white et al.,
Mounta Douglas- pine, 2005
ins, fir sugar
Oregon pine,
(Bolan Oregon
Lake) white
oak,
incense
cedar
------------------------------------------------------------------------
a Species names that are not otherwise indicated in the text: beaked
hazel (Corylus cornuta ssp. cornuta Marshall), bigleaf maple (Acer
macrophyllum Pursh), black cottonwood, (Populus trichocarpa Torr. & A.
Gray ex Hook.), incense-cedar (Calocedrus decurrens [Torr.] Florin),
Oregon ash (Fraxinus latifolia Benth.), Pacific silver fir (Abies
amabilis Douglas ex J. Forbes), sugar pine (Pinus lambertiana
Douglas), western redcedar (Thuja plicata Donn ex D. Don), western
white pine (Pinus monticola Douglas ex D. Don.), willow (Salix spp.
L.)
Paleoecological studies (covering the early Holocene and other time
periods) indicate that climate has been a major control on fire in the
Northwest over millennia, with interactions between fire and
vegetation. During times of high climatic variability and fire
frequency (e.g., the early Holocene), fires were catalysts for large-
scale shifts in forest composition and structure (Prichard, et al.,
2009; Crausbay, et al., 2017). Species that persisted during these
times of rapid change have life history traits that facilitate survival
in frequently disturbed environments (Brubaker 1988; Whitlock 1992),
including red alder, Douglas-fir, lodgepole pine, ponderosa pine, and
Oregon white oak, which suggests that these species may be successful
in a warmer future climate (Whitlock 1992; Prichard, et al., 2009).
Fire-scar and tree-ring records
Fire-scar studies indicate that climate was historically a primary
determinant of fire frequency and extent in the Northwest. Years with
increased fire frequency and area burned were generally associated with
warmer and drier spring and summer conditions in the Northwest (Hessl,
et al., 2004; Wright and Agee 2004; Heyerdahl, et al., 2008; Taylor, et
al., 2008). Climate of previous years does not have a demonstrated
effect on fire, unlike other regions such as the Southwest, most likely
because fuels are not as limiting for fire across the Northwest
(Heyerdahl, et al., 2002; Hessl, et al., 2004).
Warmer and drier conditions in winter and spring are more common
during the El Nino phase of the El Nino-Southern Oscillation (ENSO) in
the Northwest (Mote, et al., 2014). The Pacific Decadal Oscillation
(PDO) is an ENSO-like pattern in the North Pacific, resulting in sea
surface temperature patterns that appeared to occur in 20 to 30 year
phases during the twentieth century (Mantua, et al., 1997). Positive
phases of the PDO are associated with warmer and drier winter
conditions in the Northwest.
Associations between large fire years and El Nino have been found
in the interior Northwest (e.g., Heyerdahl, et al., 2002), as have
associations between large fire years and the (warm, dry) positive
phase of the PDO (Hessl, et al., 2004). Other studies have found
ambiguous or non-significant relationships between fire and these
climate cycles in the Northwest (e.g., Hessl, et al., 2004; Taylor, et
al., 2008). However, interactions between ENSO and PDO (El Nino plus
positive phase PDO) were associated with increased area burned
(Westerling and Swetnam 2003) and synchronized fire in some years in
dry forests across the inland Northwest (Heyerdahl, et al., 2008).
The PDO and ENSO likely affect fire extent by influencing the
length of the fire season (Heyerdahl, et al., 2002). Warmer and drier
winter and spring conditions increase the length of time that fuels are
flammable (Wright and Agee 2004). Although climate change effects on
the PDO and ENSO are uncertain, both modes of climatic variation
influence winter and spring conditions in the Northwest, whereas summer
drought during the year of a fire has the strongest association with
major fire years at the site and regional scales (Hessl, et al., 2004).
Summer drought conditions are likely more important than in other
regions where spring conditions are more strongly related to fire,
because the Northwest has a winter-dominant precipitation regime; fire
season occurs primarily in late summer (August through September), and
summer drought reduces fuel moisture (Hessl, et al., 2004; Littell, et
al., 2016).
Contemporary climate and fire records
In the twentieth century, wildfire area burned in the Northwest was
positively related to low precipitation, drought, and temperature
(Littell, et al., 2009; Abatzoglou and Kolden 2013; Holden, et al.,
2018). Warmer spring and summer temperatures across the western United
States cause early snowmelt, increased evapotranspiration, lower summer
soil and fuel moisture, and thus longer fire seasons (Westerling 2016).
Precipitation during the fire season also exerts a strong control on
area burned through wetting effects and feedbacks to vapor pressure
deficit (a measure of humidity; Holden, et al., 2018). Between 2000 and
2015, warmer temperatures and vapor pressure deficit decreased fuel
moisture during the fire season in 75% of the forested area in the
western U.S. and added about 9 days per year of high fire potential
(defined using several measures of fuel aridity; Abatzoglou and
Williams 2016).
Periods of high annual area burned in the Northwest are also
associated with high (upper atmosphere) blocking ridges over western
North America and the North Pacific Ocean. Blocking ridges occur when
centers of high pressure occur over a region in such a way that they
prevent other weather systems from moving through. These blocking
ridges, typical in the positive phase of the PDO (Trouet, et al.,
2006), divert moisture away from the region, increasing temperature and
reducing relative humidity (Gedalof, et al., 2005). Prolonged blocking
and more severe drought (Brewer, et al., 2012) are needed to dry out
fuels in mesic to wet forest types (e.g., Sitka spruce [Picea
sitchensis (Bong.) Carriere], western hemlock) along coastal Oregon and
Washington. With increased concentrations of carbon dioxide in the
atmosphere, the persistence of high blocking ridges that divert
moisture from the region may increase (Lupo, et al., 1997, as cited in
Flannigan, et al., 2009), further enhancing drought conditions and the
potential for fire.
Lightning ignitions also affect wildfire frequency. However,
research on lightning with recent and future climate change is
equivocal. Some studies suggest that lightning will increase up to 40%
globally in a warmer climate (Price and Rind 1994; Reeve and Toumi
1999; Romps, et al., 2014), although a recent study suggests that
lightning may decrease by as much as 15% globally (Finney, et al.,
2018).
Increases in annual area burned are generally associated with
increases in area burned at high severity. Fire size, fire severity,
and high-severity burn patch size were positively correlated in 125
fires in the North Cascades of Washington over a recent 25 year period
(Cansler and McKenzie 2014). Other analyses have similarly shown a
positive correlation between annual area burned and area burned
severely (in large patches) in the Northwest (Dillon, et al., 2011;
Abatzoglou, et al., 2017; Reilly, et al., 2017). The annual extent of
fire has increased slightly in the Northwest, although the proportion
of area burning at high severity did not increase over the 1985 to 2010
period, either for the region as a whole or for any subregion (Reilly,
et al., 2017). Similarly, an analysis of recent fires (1984 to 2014) in
the Northwest found no decrease in the proportion of unburned area
within fire perimeters (Meddens, et al., 2018).
Many studies have found that bottom-up controls such as vegetation,
fuels, and topography are more important drivers of fire severity than
climate in Western forests (e.g., Dillon, et al., 2011; Parks, et al.,
2014). The direct influence of climate on fire severity is
intrinsically much stronger in moister and higher-elevation forests,
because drying of fuels in these systems requires extended warm and dry
periods. Fire severity in many dry forest types is influenced primarily
by fuel quantity and structure (Parks, et al., 2014). However, fuel
accumulations associated with fire exclusion in dry forests may be
strengthening the influence of climate on fire severity, likely
resulting in increased fire severity in drier forest types (Parks, et
al., 2016a).
Wildfire projections under changing climate
Historical patterns suggest that higher temperatures, stable or
decreasing summer precipitation, and increased drought severity in the
Northwest will likely increase the frequency and extent of fire. Models
can help to explore potential future fire frequency and severity in a
changing climate, with several types of models being used to project
future fire (McKenzie, et al., 2004). We focused here on models for
which output is available in the Northwest-empirical (statistical)
models and mechanistic (process-based) models. Both types of models
have limitations as well as strengths, but they are conceptually useful
to assess potential changes in fire with climate change.
Fire projections by empirical models
Empirical models use the statistical relationship between observed
climate and area burned during the historical record (the past 100
years or so) to project future area burned. Future area burned is based
on projections of future temperature and precipitation, usually from
global climate models. These models do not account for the potential
decreases in burn probability in areas that have recently burned, or
for long-term changes in vegetation (and thus flammability) with
climate change (Parks, et al., 2015; McKenzie and Littell 2017;
Littell, et al., 2018). They also do not account for human influence on
fire ignitions (Syphard, et al., 2017).
Numerous studies have developed empirical models to project future
area burned or fire potential at both global (Krawchuk, et al., 2009;
Moritz, et al., 2012) and regional scales (e.g., western U.S.;
McKenzie, et al., 2004; Littell, et al., 2010; Yue, et al., 2013;
Kitzberger, et al., 2017). All studies suggest that fire potential,
area burned, or both will increase in the western U.S. in the future
with warming climate. Below we highlight a few examples that explicitly
address the Northwest. These examples provide future fire projections
at relatively coarse spatial scales, with changes in area burned being
variable across landscapes.
McKenzie, et al., (2004) projected that, with a mean temperature
increase of 2 C, area burned by wildfire will increase by a factor of
1.4 to 5 for most Western states, including Idaho, Montana, Oregon, and
Washington. Kitzberger, et al., (2017) projected increases in annual
area burned of five times the median in 2010 to 2039 compared to 1961
to 2004 for the 11 conterminous Western states. Models developed by
Littell, et al., (2010) for Idaho, Montana, Oregon, and Washington
suggested that area burned will double or triple by the 2080s, based on
future climate projections for two global climate models (Fig. 4).
Median area burned was projected to increase from about 0.2 million ha
historically to 0.3 million ha in the 2020s, 0.5 million ha in the
2040s, and 0.8 million ha in the 2080s. The projections cited here are
coarse scale, and area burned can be expected to vary from place to
place within the area of the projections.
Fig. 4
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Conceptual model showing that indirect effects of climate
change via disturbance cause faster shifts in vegetation than
do direct effects of climate change. Adapted from McKenzie, et
al. (2004 (https://fireecology.springeropen.com/articles/
10.1186/s42408-019-0062-8#ref-CR129)).
Littell, et al., (2010) also developed empirical models at a finer
(ecosection) scale for the state of Washington. The relatively low
frequency of fire in coastal forests makes development of empirical
models difficult, so the output from these models for coastal forests
is uncertain. For drier forest types, potential evapotranspiration and
water balance deficit were the most important variables explaining area
burned. In forested ecosystems (Western and Eastern Cascades, Okanogan
Highlands, and Blue Mountains ecosections), the mean area burned was
projected to increase by a factor of 3.8 in the 2040s compared to 1980
to 2006. An updated version of these models, expanded to the western
U.S. (Littell, et al., 2018), also suggests that area burned will
increase in the future for most forested ecosections of the Northwest,
but increases in area burned may be tempered, or area burned may
decrease, in areas that are more fuel limited (e.g., in non-forest
vegetation types).
Another application of empirical models is to project the future
incidence of very large fires, often defined as the largest 5 to 10% of
fires or fires >5,000 ha. Barbero, et al., (2015) projected that the
annual probability of very large fires will increase by a factor of
four in 2041 to 2070 compared to 1971 to 2000. Projections by Davis, et
al., (2017) suggested that the proportion of forests highly suitable
for fires >40 ha will increase by >20% in the next century for most of
Oregon and Washington, but less so for the Coast Range and Puget
Lowlands. The largest projected increases were in the Blue Mountains,
Klamath Mountains, and East Cascades. The number of fires that escape
initial attack will also likely increase (Fried, et al., 2008).
Few empirical model projections are available for future fire
severity. Using empirical models, Parks, et al., (2016a) suggested that
fire severity in a warming climate may not change significantly in the
Northwest, because fuels limit fire severity. However, altered fire
severity will depend partly on vegetation composition and structure (as
they affect fuels), and climate change is expected to alter vegetation
composition and structure both directly and indirectly (through
disturbance). Empirical models do not account for these potential
changes in vegetation and fuels (among other limitations; see McKenzie
and Littell 2017). In the near term, high stem density as a result of
fire exclusion and past management may increase fire severity in dry,
historically frequent-fire forests (Haugo, et al., 2019).
Fire projections by mechanistic models
Mechanistic models allow for exploration of potential interactions
between vegetation and fire under changing and potentially novel
climate. Mechanistic models can also account for elevated carbon
dioxide concentration on vegetation, which could result in increased
vegetation productivity (and fuel loading). Examples of mechanistic
models that simulate fire include dynamic global vegetation models,
such as MC1 (Bachelet, et al., 2001), LANDIS-II (Scheller and Mladenoff
2008), and Fire-BioGeoChemical (Fire-BGC; Keane, et al., 1996).
Using the MC1 dynamic global vegetation model for the western \3/4\
of Oregon and Washington, Rogers, et al., (2011) projected a 76 to 310%
increase in annual area burned and a 29 to 41% increase in burn
severity (measured as aboveground carbon consumed by fire) by the end
of the twenty-first century, with the degree of increase depending on
climate scenario. These projected changes were largely driven by
increased summer drought. Under a hot and dry climate scenario (with
more frequent droughts), large fires were projected to occur throughout
the twenty-first century (including the early part), primarily in mesic
forests west of the Cascade crest.
Using the MC2 model (an updated version of MC1), Sheehan, et al.,
(2015) also projected increasing fire activity in Idaho, Oregon,
Washington, and western Montana. Mean fire return interval was
projected to decrease across all forest-dominated subregions, with or
without fire suppression. Projected decreases in mean fire interval
were as high as 82% in the interior subregions without fire
suppression; projected decreases in mean fire interval for the
westernmost subregion were as high as 48% without fire suppression.
The MC1 and MC2 models have also been calibrated and run for
smaller subregions in the Northwest. For the Willamette Valley, Turner,
et al., (2015) projected (under a high temperature increase scenario)
increased fire frequency, with average area burned per year increasing
by a factor of nine relative to the recent historical period (1986 to
2010); area burned over the recent historical period was very low (0.2%
of the area per year). For a western Washington study region, MC2
projected a 400% increase in annual area burned in the twenty-first
century compared to 1980 to 2010 (Halofsky, et al., 2018a). Although
the projected average annual area burned was still only 1.2% of the
landscape, some fire years were very large, burning 10 to 25% of the
study region.
The MC1 model projected increased fire frequency and extent in
forested lands east of the Cascade crest (Halofsky, et al., 2013;
Halofsky, et al., 2014). Fire was projected to burn more than 75% of
forested lands several times between 2070 and 2100. On average,
projected future fires burned the most forest under a hot, dry
scenario. Applying the MC2 model to a larger south-central Oregon
region, Case, et al., (2019) suggested that future fire will become
more frequent in most vegetation types, increasing most in dry and
mesic forest types. For forested vegetation types, fire severity was
projected to remain similar or increase slightly compared to historical
fire severity.
The LANDIS-II model has been applied to the Oregon Coast Range in
the Northwest. Creutzburg, et al., (2017) found that area burned over
the twenty-first century did not increase significantly with climate
change compared to historical levels, but fire severity and extreme
fire weather did increase.
Fire-BGC models have mostly been applied in the northern U.S. Rocky
Mountains, which overlaps with the Northwest. For northwestern Montana
(Glacier National Park), Keane, et al., (1999) used Fire-BGC in a
warmer, wetter climate scenario to project higher vegetation
productivity and fuel accumulations that contribute to more intense
crown fires and larger fire sizes. Fire frequency also increased over a
250 year simulation period: fire rotation decreased from 276 to 213
years, and reburns occurred in 37% of the study area (compared to 17%
under historical conditions). In drier locations (low-elevation south-
facing sites), low-severity surface fires were more common, with fire
return intervals of 50 years.
Mechanistic modeling suggests that fire frequency and area burned
will increase in the Northwest. Fire severity may also increase,
depending partly on forest composition, structure, and productivity
over time. Warmer temperatures in winter and spring, and increased
precipitation during the growing season (even early in the growing
season), could increase forest productivity. This increase in
productivity would maintain or increase fuel loadings and promote high-
severity fires when drought and ignitions occur. In mechanistic model
projections for the region, some of the largest increases in fire
severity (Keane, et al., 1999; Case, et al., 2019) and the largest
single fire years (Halofsky, et al., 2013; Halofsky, et al., 2018a)
occurred in wetter scenarios with increased forest productivity. Future
increased fire frequency without increased vegetation productivity is
likely to result in decreased fire severity because of reduction in
fuels as well as the potential for type conversion to vegetation
characterized by less woody biomass. However, in highly productive
systems such as forests west of the Cascade crest, future fires will
probably be high severity (as they were historically) and more frequent
(Rogers, et al., 2011; Halofsky, et al., 2018a).
Short-interval reburns
A reburn occurs when the perimeter of a recent past fire is
breached by a subsequent fire, something that all fire-prone forests
have experienced. In the Northwest, reburns in the early twentieth
century were documented in some of the earliest forestry publications
(e.g., Isaac and Meagher 1936). However, under a warming climate,
increased frequency and extent of fire will increase the likelihood of
reburns, increasing the need to understand how earlier fires affect
subsequent overlapping fires and how forests respond to multiple fires.
Recent concern about reburns centers on projections that short-
interval, high-severity (i.e., stand-replacing) reburns may become more
common (Westerling, et al., 2011; Prichard, et al., 2017). Multiple
fires can interact as linked disturbances (Simard, et al., 2011),
whereby the first fire affects the likelihood of occurrence, size, or
magnitude (intensity, severity) of a reburn. Multiple fires can also
interact to produce compound disturbance effects (Paine, et al., 1998),
in which ecological response after a reburn is qualitatively different
than after the first fire.
Effects of past fire on future fire occurrence
Interactions between past forest fires and the occurrence of
subsequent fires are generally characterized by negative feedbacks:
fires are less likely to start within or spread into recently burned
areas (i.e., within the last 5 to 25 years) compared to similar areas
that have not experienced recent fire. For example, lightning-strike
fires within the boundary of recently burned areas in the U.S. Rocky
Mountains (Idaho, Montana) were less likely to grow to fires larger
than 20 ha than were lightning-strike fires in comparable areas outside
recent fire boundaries (Parks, et al., 2016b). This negative relation
between past fires and likelihood of future fires is generally
attributed to limits on ignition potential and initial spread of fires
through fine woody fuels, which are sparse following fire. Fine fuels
are consumed by the first fire and do not recover to sufficient levels
until at least a decade later in many interior forest systems in the
Northwest (Isaac 1940; Donato, et al., 2013) and U.S. Rocky Mountains
(Nelson, et al., 2016, 2017). However, negative feedbacks can be short-
lived (or non-existent) in productive west-side forests in the
Northwest, where fuels are abundant in early-successional forests
(Isaac 1940; Agee and Huff 1987; Gray and Franklin 1997).
Past fires in the northern U.S. Rocky Mountains have also been
effective at preventing the spread of subsequent fires into their
perimeters (Teske, et al., 2012; Parks, et al., 2015). Similar results
have been found in mixed-conifer forests of the interior Northwest,
where past wildfire perimeters inhibited the spread of the 2007 Tripod
Complex Fire in eastern Washington (Prichard and Kennedy 2014). This
limitation of fire spread decreases with time. The probability that
reburns will be inhibited by earlier fires is near 100% in the first
year post fire, but is only 30% by 15 to 20 years post fire (Parks, et
al., 2015). However, extreme fire weather can dampen buffering effects
of reburns at any interval between fires, such that past fire
perimeters become less effective at inhibiting reburns during warm,
dry, and windy conditions (Parks, et al., 2015).
Effects of past fire on future fire severity
Fire severity (fire-caused vegetation mortality) in a reburn is
affected by interactions among severity of the first fire, climate
setting and forest type, interval between fires, and weather at the
time of the reburn. Reburns are typically less severe when the interval
between fires is shorter than 10 to 15 years (Parks, et al., 2014;
Harvey, et al., 2016b; Stevens-Rumann, et al., 2016). After 10 to 15
years, the effects of past fires on reburn severity diverge in
different ecological contexts.
In areas where tree and shrub regeneration is prolific following
one severe fire (e.g., moist Douglas-fir forests, subalpine forests
dominated by lodgepole pine, some mixed-conifer forests [e.g.,
southwest Oregon mixed conifer forests with a hardwood component]),
fire severity can be greater in reburns than in comparable single burns
once the interval between fires exceeds 10 to 12 years (Thompson, et
al., 2007; Harvey, et al., 2016b). In lower-elevation, drier, and more
fuel-limited forests (e.g., ponderosa pine forests and woodlands, areas
with slower woody plant establishment following fire), past fire limits
future fire severity, often for 20 to 30 years (Parks, et al., 2015;
Harvey, et al., 2016b; Stevens-Rumann, et al., 2016). In these lower-
productivity forests, the severity of past fire has been found to be
the best predictor of reburn severity (Parks, et al., 2014; Harvey, et
al., 2016b), but this is not necessarily the case in higher-
productivity forests (Thompson, et al., 2007; Stevens-Rumann, et al.,
2016). Surface fuel treatment followed by tree planting can greatly
reduce the intensity of a reburn and allow most newly established trees
to survive (Lyons-Tinsley and Peterson 2012).
Of particular concern for forest resilience is how and why forests
may experience two severe fires in short succession. In the northern
U.S. Rocky Mountains, the likelihood of experiencing two successive
stand-replacing fires (i.e., a severe fire followed by a severe reburn)
is greatest (1) in areas with high post-fire regeneration capacity
(e.g., higher-elevation subalpine forests on moist sites), and (2) when
the reburn occurs during warm, dry conditions (Harvey, et al., 2016b).
In high-productivity west-side forests of Oregon and Washington, the
potential for two successive high-severity burns may always exist
(e.g., Isaac 1940), but occurrence depends on ignition and low fuel
moisture.
Effects of reburns on forest species composition and structure
Short-interval reburns can produce compound effects on tree
regeneration, altering species composition in some cases and shifting
to non-forest vegetation in others. For example, thin-barked species,
which do not survive fire but instead regenerate from seed following
fire-induced mortality (e.g., lodgepole pine), can face ``immaturity
risk'' if the interval between one fire and a reburn is too short to
produce a sufficient canopy seedbank (Keeley, et al., 1999; Turner, et
al., 2019). In northern U.S. Rocky Mountain systems, low- and moderate-
severity reburns have shifted dominance from lodgepole pine toward
thick-barked species that can resist fire, such as ponderosa pine
(Larson, et al., 2013; Stevens-Rumann and Morgan 2016).
In the western Cascades of southern Washington, areas that burned
in the 1902 Yacolt Burn and subsequently reburned within 30 years were
characterized by much lower conifer regeneration than areas that burned
only once (Gray and Franklin 1997). However, in the Klamath and
Siskiyou mountains of southwestern Oregon, a short-interval (15 years
between fires), high-severity reburn had no compound effect on
regeneration (2 years post fire) of Douglas-fir, the dominant tree
species (Donato, et al., 2009b), with no difference from areas that
burned once at a longer interval (>100 years between fires). Plant
species diversity and avian diversity were higher in reburns compared
to once-burned areas, with hardwoods contributing to habitat diversity
in the reburn areas (Donato, et al., 2009b; Fontaine, et al., 2009).
The effects of reburns on post-fire conifer regeneration seem to
depend on legacy trees that survive both fires, providing seed across
fire events (Donato, et al., 2009b). In systems where legacy trees are
rare (i.e., thin-barked species easily killed by fire) or where shrubs
and hardwoods can outcompete trees for long durations, reburns are more
likely to produce lasting compound effects on forest structure and
composition, possibly resulting in a shift to non-forest vegetation.
Disturbance and stress interactions
Combinations of biotic and abiotic stressors, or stress complexes,
will likely be major drivers of shifts in forest ecosystems with
changing climate (Manion 1991). A warmer climate will affect forests
directly through soil moisture stress and indirectly through increased
extent and severity of disturbances, particularly fire and insect
outbreaks (McKenzie, et al., 2009).
Water deficit and disturbance interactions
Although water deficit (the condition in which potential summer
atmospheric and plant demands exceed available soil moisture) is rarely
fatal by itself, it is a predisposing factor that can exacerbate the
forest stress complex (Manion 1991; McKenzie, et al., 2009). Water
deficit directly contributes to potentially lethal stresses in forest
ecosystems by intensifying negative water balances (Stephenson 1998;
Milne, et al., 2002; Littell, et al., 2008; Restaino, et al., 2016).
Water deficit also indirectly increases the frequency, extent, and
severity of disturbances, especially wildfire and insect outbreaks
(McKenzie, et al., 2004; Logan and Powell 2009). These indirect
disturbances alter forest ecosystem structure and function, at least
temporarily, much faster than do chronic effects of water deficit
(e.g., Loehman, et al., 2017; Fig. 4).
Interactions among drought, insect outbreaks, and fire
During the past few decades, wildfires and insect outbreaks have
affected a large area across the Northwest (Fig. 5). Increased area
burned has been at least partly caused by extreme drought-wildfire
dynamics, which will likely become more prominent as drought severity
and area burned increase in the future (Parks, et al., 2014; McKenzie
and Littell 2017). Insect disturbance has likewise expanded across the
Northwest since 1990, catalyzed by higher temperature and the
prevalence of dense, low-vigor forests. Cambium feeders, such as bark
beetles, are associated with prolonged droughts, in which tree defenses
are compromised (Logan and Bentz 1999; Carroll, et al., 2004; Hicke, et
al., 2006). Patches of fire-insect disturbance mosaic are starting to
run into each other (Fig. 5), and similar to reburns, are an inevitable
consequence of increasing disturbance activity, even in the absence of
mechanistic links among disturbances.
Fig. 5
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Recent disturbances in the Northwest, USA, showing wildfire
extent for 1984 to 2017 (orange), and insect and disease extent
for 1997 to 2017 (brown). Data sources: Monitoring Trends in
Burn Severity (https://www.mtbs.gov) and U.S. Forest Service
Insect and Disease Detection Survey (https://www.fs.fed.us/
foresthealth/applied-sciences/mapping-reporting/gis-spatial-
analysis/detection-surveys.shtml). Map credit: Robert Norheim.
In a review of the fire-bark beetle literature, Hicke, et al.
(2012) noted that, despite varying research approaches and questions,
much agreement existed on fire hazard (defined as changes to fuels and
potential fire behavior) after bark beetle outbreaks. There was strong
agreement that surface fire and torching potential increased during the
gray phase (e.g., 5 to 10 years following outbreaks, when snags remain
standing; but see Woolley, et al., 2019), but that crown fire potential
was reduced in this phase. Similarly, there was agreement that fire
hazard was lower in the old phase (i.e., silver phase), which occurs 1
to several decades after outbreak, when beetle-killed snags have
fallen, understory vegetation increases, and seedlings establish.
However, there was disagreement regarding fire potential during the red
phase (0 to 4 years after outbreak initiation), when trees retain their
drying needles and changes in foliar chemistry can increase
flammability. Many studies have concluded that during this
approximately 1 to 4 year period, fire hazard increases (Klutsch, et
al., 2011 [but see Simard, et al., 2011], Hoffman, et al., 2012, Jolly,
et al., 2012; Jenkins, et al., 2014). Fire hazard has been found to
increase as the proportion of the stand killed by bark beetles
increases, regardless of forest type (Page and Jenkins 2007; DeRose and
Long 2009; Hoffman, et al., 2012).
Concern has also risen as to whether fire occurrence and severity
will increase following outbreaks of bark beetles (e.g., Hoffman, et
al., 2013), although empirical support for such interactions has been
lacking (Parker, et al., 2006; Hicke, et al., 2012). Insect outbreaks
have not been shown to increase the likelihood of fire or area burned
(Kulakowski and Jarvis 2011; Flower, et al., 2014; Hart, et al., 2015;
Meigs, et al., 2015). Further, when fire occurs in post-outbreak
forests, most measures of fire severity related to fire-caused
vegetation mortality are generally similar between beetle-affected
forests and areas that were unaffected by pre-fire outbreaks. Field
studies in Oregon showed that burn severity (fire-caused vegetation
mortality) was actually lower in lodgepole pine forests affected by
mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins) than
analogous unaffected forests that burned (Agne, et al., 2016). In an
analysis of recent (1987 to 2011) fires across the Northwest, Meigs, et
al., (2016) also found that burn severity (from satellite-derived burn
severity indices) was lower in forests with higher pre-fire insect
outbreak severity.
Field studies in California, the Rocky Mountains, and interior
British Columbia, Canada, conducted in a range of forest types have
also explored the relationship between beetle outbreak severity (pre-
fire basal area killed by beetles) and burn severity (fire-caused
vegetation mortality), and suggest relatively minor effects of beetle
outbreaks on burn severity. When fire burned through red stages (1 to 4
years post outbreak, when trees retain red needles) in dry conifer
forests of California, small increases (e.g., 8 to 10% increase in
fire-caused tree mortality) in burn severity were observed in areas of
high outbreak severity (Stephens, et al., 2018). In dry Douglas-fir
forests in Wyoming, fire severity in the gray phase (4 to 10 years post
outbreak) of Douglas-fir beetle (Dendroctonus pseudotsugae Hopkins)
outbreak was unaffected by beetle outbreak severity (Harvey, et al.,
2013). Similar results of minimal beetle effect on fire severity were
reported in gray-stage spruce-fir forests in Colorado, USA (Andrus, et
al., 2016). In lodgepole pine-dominated forests affected by MPB,
outbreak effects on burn severity differed by weather and stage of
outbreak. For example, in both green and red phases (when most beetle-
killed trees retained crowns fading from green to red), fire severity
increased with pre-fire beetle outbreak severity under moderate but not
extreme (e.g., hot, dry, windy) weather (Harvey, et al., 2014a).
Conversely, in the red and gray stages, fire severity increased with
pre-fire outbreak severity under extreme but not moderate weather
(Harvey, et al., 2014b).
In British Columbia, gray-stage post-outbreak stands did not burn
more severely than unaffected stands for most measures of burn severity
(Talucci, et al., 2019). The effects of beetle outbreaks on fire
severity in forest types typified by stand-replacing fire regimes seem
to be overall variable and minor, especially given that such forest
types are inherently characterized by severe fire. The key exception to
the otherwise modest effects of pre-fire beetle outbreaks on burn
severity is the effect of deep wood charring and combustion on beetle-
killed snags that burn. This effect has been reported across stages and
forest type when measured, and consistently increases with pre-fire
beetle outbreak severity (Harvey, et al., 2014b; Talucci, et al.,
2019). Because fire intensity and thus severity are driven by
topography, weather, and fuels, beetle-outbreak-induced changes to fuel
structures may play a minor role in affecting fire severity. In all
cases in studies above where topography and weather were quantified,
fire severity responded strongly and consistently to these factors
irrespective of pre-fire beetle outbreaks.
In the Northwest, lodgepole pine forests have been affected by MPB
outbreaks, with high mortality in some locations (e.g., Okanogan-
Wenatchee Forest; Fig. 6). Widely distributed at mid to higher
elevations in the Rocky Mountains, lodgepole pine is the dominant
species over much of its range there, forming nearly monospecific
stands. In the Northwest, lodgepole pine occurs at mid to higher
elevations in the Cascade Range and eastward, and monospecific stands
are limited to early seral stages and specific soil conditions (e.g.,
Pumice Plateau in central Oregon). In some populations in the
Northwest, lodgepole pine forests have also adapted to stand-replacing
fires via cone serotiny.
Fig. 6
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Number of trees killed by beetles in Okanogan-Wenatchee
National Forest, Washington, USA, from 1980 to 2016. Data
source: C. Mehmel, Okanogan-Wenatchee National Forest,
Washington, USA.
Bark beetle outbreaks and subsequent fire may interact to affect
post-fire forest recovery, but results differ depending on the dominant
regeneration mechanism of the tree attacked by beetles. Species with a
persistent canopy seedbank, such as lodgepole pine, are minimally
affected by compound disturbances between beetle outbreaks and fire.
For example, in the Cascade Range and Rocky Mountains, areas that
experienced beetle outbreaks prior to fire had similar levels of post-
fire lodgepole pine seedling establishment compared to areas that had
fire only (Harvey, et al., 2014a; Harvey, et al., 2014b; Edwards, et
al., 2015; Agne, et al., 2016). Species such as Douglas-fir, which do
not have a persistent canopy seedbank, have been shown to have lower
post-fire seedling establishment in areas affected by Douglas-fir
beetle outbreaks and fire (Harvey, et al., 2013), although effects may
be transient and disappear with time since fire (Stevens-Rumann, et
al., 2015).
Interactions among fungal pathogens and other stressors
The effects of weather and climate on fungal pathogens vary by
species, with the spread of some pathogens facilitated by drought and
others by wet periods (Klopfenstein, et al., 2009; Sturrock, et al.,
2011; Ayres, et al., 2014). Forests with low vigor and physiologically
stressed trees (e.g., dense stands) are generally more susceptible to
fungal pathogens. In the Northwest, a wide range of root rots and other
native fungal pathogens exists in all forest types. For example, on the
west side of the Cascade Range, laminated root rot (Phellinus weirii
[Murrill] Gilb.) is widespread, causing small pockets of mortality in
Douglas-fir (Agne, et al., 2018). However, no evidence exists that this
pathogen has been or will be accelerated by a warmer climate. Other
pathogens, such as Swiss needle cast (Phaeocryptopus gaeumannii [T.
Rohde] Petrak), may be favored by warmer and wetter winters (Agne, et
al., 2018). Fungal pathogens stress trees and may increase
susceptibility to insect infestations. For example, Douglas-fir beetle
is closely associated with laminated root rot centers in forests on the
west side of the Cascades in Oregon and Washington (Goheen and Hansen
1993). Overall, interactions between fungal pathogens and fire with
climate change are uncertain.
Stress complexes and forest mortality
Recent large-scale tree mortality events in the Southwest
(Breshears, et al., 2005), Texas (Schwantes, et al., 2016), and
California, USA (Young, et al., 2017), have been caused by multi-year
droughts weakening trees, followed by various beetle species acting as
the mortality agents. It is likely that more intense and longer
droughts will increase in the future under changing climate (Trenberth,
et al., 2014), and interactions between drought and other disturbance
agents are likely to cause tree mortality. As noted above, fungal
pathogens may contribute to increasing insect outbreaks (Goheen and
Hansen 1993), along with increasing temperatures, shorter winters, and
tree stress. Fire-caused tree mortality will also likely be affected by
interacting disturbances. In some cases, fire severity has been
marginally higher in areas affected by beetle mortality (Harvey, et
al., 2014a; Harvey, et al., 2014b; Stephens, et al., 2018). However,
empirical studies examining the effects of large-scale tree mortality
events on fire behavior are limited (Stephens, et al., 2018). Modeling
studies suggest that fire rate of spread may increase after mortality
events (e.g., Perrakis, et al., 2014).
Effects of changing disturbance regimes on forest structure and
composition
In Northwest forest ecosystems, warming climate and changing
disturbance regimes are likely to lead to changes in species
composition and structure, probably over many decades. In general,
increased fire frequency will favor plant species with life history
traits that allow for survival with more frequent fire (Chmura, et al.,
2011). These include (1) species that can resist fires (e.g., thick-
barked species such as Douglas-fir, western larch [Larix laricina
Nutt.], and ponderosa pine); (2) species with high dispersal ability
that can establish after fires (e.g., Douglas-fir); and (3) species
with serotinous cones that allow seed dispersal from the canopy after
fire (e.g., lodgepole pine) (Rowe 1983; Agee 1993).
In the forest understory, increased fire frequency and extent will
likely create more opportunities for establishment by invasive species
(Hellmann, et al., 2008). Species that can endure fires (sprouters) and
seedbank species (evaders) are also likely to increase with more
frequent fire. For example, sprouting shrubs and hardwoods are prolific
after fire in southwest Oregon (Halofsky, et al., 2011). However, high-
intensity fire can consume or kill seeds stored in the upper soil
layers and kill shallow belowground plant parts, and repeated fires at
short intervals can deplete seed stores and belowground plant resources
(Zedler, et al., 1983).
More frequent fire will likely decrease abundance of avoider
species, including shade-tolerant species, species with thin bark, and
slow invaders after fire (Chmura, et al., 2011). Forest stands composed
primarily of fire-susceptible evader species, such as western hemlock,
subalpine fir, and Engelmann spruce (Picea engelmannii Parry ex
Engelm.), will likely have higher mortality for a given fire intensity
than stands composed of more fire-resistant species, such as mature
Douglas-fir and western larch. If fire-sensitive species are not able
to re-seed into burned areas and re-establish themselves (because of
short fire intervals, competition, or harsh conditions for seedling
establishment), these species can be lost from a site (Stevens-Rumann
and Morgan 2016). Direct mortality or lack of regeneration of fire-
sensitive species with more frequent fire will favor more fire-adapted
species that can survive fire or regenerate after fire. For example, in
southwest Oregon, shrubs and hardwoods are likely to increase in
abundance with increased fire frequency and reduced conifer
regeneration in some locations (Tepley, et al., 2017).
Changes in disturbance regimes can influence the structure of
forests at multiple spatial scales (Reilly, et al., 2018). Within
forest stands, more frequent fire will likely decrease tree density in
dry forests, and open savannas may increase in area. Forest
understories may shift from being duff- or forb-dominated to shrub- or
grass-dominated. Tree canopy base heights will likely increase as
frequent fires remove lower branches. Across forested landscapes (i.e.,
among stands), fire directly influences the spatial mosaic of forest
patches (Agee 1993). More extreme fire conditions with climate change
may initially lead to larger and more frequent fires, resulting in
larger burn patch sizes and greater landscape homogeneity (Harvey, et
al., 2016a). More frequent severe fire will likely decrease forest age,
the fraction of old-growth forest patches, and the landscape
connectivity of old-growth forest patches (Baker 1995; McKenzie, et
al., 2004). However, more frequent low- and mixed-severity fires may
eventually reduce fuels in drier forest ecosystems (e.g., dry mixed
conifer), leading to lower-intensity fires and a finer-scale patch
mosaic (Chmura, et al., 2011).
Effects of climate change on post-fire processes
Forest regeneration
Changing climate and fire frequency, extent, and severity are
likely to influence forest regeneration processes, thus affecting the
structural and compositional trajectories of forest ecosystems. First,
climate change is expected to affect regeneration through increased
fire frequency. As fire-free intervals shorten, the time available for
plants to mature and produce seed before the next fire will be limited.
Such changes in fire-free intervals can have significant effects on
post-fire regeneration, because different plants have varied
adaptations to fire. Species that resprout following fire may decline
in density, but species that are fire-killed and thus require
reproduction from seed may be locally eliminated.
Second, climate change may result in increased fire severity. If
the size of high-severity fire patches increases, seed sources to
regenerate these patches will be limited. Regeneration of non-
serotinous species will require long-distance seed dispersal and may be
slower in large, high-severity patches (Little, et al., 1994; Donato,
et al., 2009a; Downing, et al., 2019).
Third, climate change will likely result in increased forest
drought stress. Warmer temperatures, lower snowpack, and increased
evapotranspiration will increase summer drought stress. Warmer and
drier conditions after fire events may cause recruitment failures,
particularly at the seedling stage (Dodson and Root 2013). In this way,
fire can accelerate species turnover when climatic conditions are
unfavorable for establishment of dominant species (Crausbay, et al.,
2017) and seed sources are available for alternative species.
Regeneration in dry forests in the Northwest (e.g., ponderosa pine)
may be particularly sensitive to changing climate. Hotter and drier
sites (e.g., on southwestern aspects) may be particularly at risk for
regeneration failures (Nitschke, et al., 2012; Dodson and Root 2013;
Donato, et al., 2016; Rother and Veblen 2017; Tepley, et al., 2017).
High soil surface temperatures can also cause mortality (Minore and
Laacke 1992). Forest structure (mainly shade from an existing canopy)
can ameliorate harsh conditions and allow for regeneration (Dobrowski,
et al., 2015). However, after high-severity disturbance, dry forests at
the warm and dry edges of their distribution (ecotones) may convert to
grasslands or shrublands in a warming climate (Johnstone, et al., 2010;
Jiang, et al., 2013; Savage, et al., 2013; Donato, et al., 2016;
Stevens-Rumann, et al., 2017).
In the Klamath-Siskiyou ecoregion of southwestern Oregon and
northern California, Tepley, et al., (2017) found that conifer
regeneration was reduced by low soil moisture after fires. With lower
soil moisture, greater propagule pressure (smaller high-severity
patches with more live seed trees) was needed to achieve a given level
of regeneration. This suggests that, at high levels of climatic water
deficit, even small high-severity patches are at risk for low post-fire
conifer regeneration. Successive fires could further limit conifer seed
sources, thus favoring shrubs and hardwoods.
Germination of ponderosa pine is favored by moderate temperatures
and low moisture stress, and survival increases when maximum
temperatures are warm (but not hot) and when growing season rainfall is
above average (Petrie, et al., 2016; Rother and Veblen 2017). Empirical
modeling by Petrie, et al., (2017) projected that, with warming
temperature in the middle of the twenty-first century, regeneration
potential of ponderosa pine may increase slightly on many sites.
However, by the end of the century, with decreased moisture
availability, regeneration potential in the Northwest decreased by 67%
in 2060 to 2099 compared to 1910 to 2014. In the eastern Cascade Range
of Oregon, Dodson and Root (2013) found decreasing ponderosa pine
regeneration with decreasing elevation and moisture availability,
suggesting that moisture stress would limit regeneration.
Several studies in the Rocky Mountains have also found decreased
post-fire regeneration with increased water deficits on drier, lower-
elevation sites (Rother, et al., 2015; Donato, et al., 2016; Stevens-
Rumann, et al., 2017; Davis, et al., 2019). Donato, et al., (2016)
found decreased regeneration of Douglas-fir 24 years after fire on
drier, lower-elevation sites compared to more mesic sites at higher
elevations. Regeneration declined with higher burn severity and was
minimal beyond 100 to 200 m from a seed source. Similarly, Harvey, et
al., (2016c) found that post-fire tree seedling establishment decreased
with greater post-fire drought severity in subalpine forests of the
northern U.S. Rocky Mountains; post-fire subalpine fir and Engelmann
spruce regeneration were both negatively affected by drought. Davis, et
al., (2019) modeled post-fire recruitment probability for ponderosa
pine and Douglas-fir on sites in the Rocky Mountains, and found that
recruitment probability decreased between 1988 and 2015 for both
species, suggesting a decline in climatic suitability for post-fire
tree regeneration.
In a study of annual regeneration and growth for 10 years following
wildfire in the eastern Cascade Range of Washington, Littlefield (2019)
found that establishment rates of lodgepole pine (and other species)
were highest when growing seasons were cool and moist. A lagged climate
signal was apparent in annual growth rates, but standardized climate-
growth relationships did not vary across topographic settings,
suggesting that topographic setting did not decouple site conditions
from broader climatic trends to a degree that affected growth patterns.
These results underscore the importance of favorable post-fire climatic
conditions in promoting robust establishment and growth while
highlighting the importance of topography and stand-scale processes
(e.g., seed availability and delivery). Although concerns about post-
fire regeneration failure may be warranted under some conditions,
failure is not a general phenomenon in all places and at all times
(Littlefield 2019).
If warming climate trends continue as projected, without (or even
with) tree planting, loss of forests may occur on the driest sites in
the Northwest (Donato, et al., 2016; Harvey, et al., 2016c; Stevens-
Rumann, et al., 2017), particularly east of the Cascade crest and in
southwestern Oregon. Individual drought years are not likely to alter
post-fire successional pathways, especially if wet years occur between
dry years (Tepley, et al., 2017; Littlefield 2019). Recruitment of
conifers following a disturbance can require years to decades in the
Northwest (Little, et al., 1994; Shatford, et al., 2007; Tepley, et
al., 2014). Thus, shrubs or grasses may dominate during drought
periods, but conifers could establish and overtop shrubs and grasses
during wetter and cooler periods (Dugan and Baker 2015; Donato, et al.,
2016).
Management actions
More frequent and larger wildfires in Northwest forests will likely
be a major challenge facing resource managers of public and private
lands in future decades (Peterson, et al., 2011a). Adapting forest
management to climate change will help forest ecosystems transition to
new conditions, while continuing to provide timber, water, recreation,
habitat, and other benefits to society. Starting the process of
adaptation now, before the marked increase in wildfire expected by the
mid twenty-first century, will likely improve options for successful
outcomes. Fortunately, some current forest management practices,
including stand density management and surface fuel reduction in dry
forests, and control of invasive species, are ``climate smart'' because
they increase resilience to changing climate and disturbances
(Peterson, et al., 2011a; Peterson, et al., 2011b).
Resource managers will likely be unable to prevent increasing
broad-scale trends in area burned with climate change, but fuel
treatments can decrease fire intensity and severity locally (Agee and
Skinner 2005; Peterson, et al., 2005). In drought- and fire-prone
forests of the Northwest (e.g., ponderosa pine and dry mixed-conifer
forests east of the Cascades and in southwestern Oregon), reducing
forest density can decrease crown fire potential (Agee and Skinner
2005; Safford, et al., 2012; Martinson and Omi 2013; Shive, et al.,
2013), and negative effects of drought on tree growth (Clark, et al.,
2016; Sohn, et al., 2016). Even in wetter forest types, reducing stand
density can increase water availability, tree growth, and tree vigor by
reducing competition (Roberts and Harrington 2008). Decreases in forest
stand density, coupled with hazardous fuel treatments, can also
increase forest resilience to wildfire in dry forest types (Agee and
Skinner 2005; Stephens, et al., 2013; Hessburg, et al., 2015).
In dry forests, forest thinning prescriptions may need to reduce
forest density to increase forest resistance and resilience to fire,
insects, and drought (Peterson, et al., 2011a; Sohn, et al., 2016). For
example, in anticipation of a warmer climate and increased fire
frequency, managers in Okanogan-Wenatchee National Forest in eastern
Washington are currently basing stocking levels for thinning and fuel
treatments on the next driest forest type. Thinning and fuel treatments
could also be prioritized in (1) locations where climate change
effects, particularly increased summer drought, are expected to be most
pronounced (e.g., on south-facing slopes); (2) high-value habitats; and
(3) high-risk locations such as the wildland-urban interface. Fuel
treatments must be maintained over time to remain effective (Agee and
Skinner 2005; Peterson, et al., 2005). Insufficient financial
resources, agency capacity constraints, and air quality constraints on
prescribed burning are harsh realities that will in most cases limit
the extent of fuel treatments (Melvin 2018), necessitating strategic
implementation of treatments in locations where fuel reduction will
maximize ecological, economic, and political benefits.
Fewer options exist for reducing fire severity in wetter, high-
elevation and coastal forests of the Northwest, historically
characterized by infrequent, stand-replacement fire regimes (Halofsky,
et al., 2018b). In these ecosystems, thinning and hazardous fuel
treatments are unlikely to significantly affect fire behavior, because
fires typically occur under extreme weather conditions (i.e., during
severe drought). However, managers may consider installing fuel breaks
around high-value resources, such as municipal watersheds, key wildlife
habitats, and valuable infrastructure, to reduce fire intensity and
facilitate fire suppression efforts (Syphard, et al., 2011). In
addition, ecosystem resilience to a warmer climate is likely to improve
by promoting landscape heterogeneity with diverse species and stand
structures, and by reducing the effects of existing non-climatic
stressors on ecosystems, such as landscape fragmentation and invasive
species (Halofsky, et al., 2018b).
The future increase in fire will put late-successional forest at
risk, potentially reducing habitat structures (large trees, snags,
downed wood) that are important for many plant and animal species. In
dry forests, some structures can be protected from fire by thinning
around them and reducing organic material at their base (Halofsky, et
al., 2016). To increase habitat quality and connectivity, increasing
the density of these structures may be particularly effective in
younger forests, especially where young forests are in close proximity
to late-successional forest.
Regeneration failures after fire are a risk with changing climate,
particularly for drier forests. A primary method to help increase
natural post-fire regeneration is to increase seed sources by both
reducing fire severity (through fuel treatments and prescribed fire)
and increasing the number of live residual trees (Dodson and Root
2013). In areas adjacent to green trees, natural regeneration may be
adequate. In locations farther than 200 m from living trees, managers
may want to supplement natural regeneration with planting where costs
are not prohibitive because of remoteness or topography (North, et al.,
2019). Where post-fire planting is desirable, managers may consider
changes from current practices. For example, they may want to consider
lowering stocking density and increasing the spatial heterogeneity of
plantings to increase resilience to fire and drought (North, et al.,
2019). Planting seedlings on cooler, wetter microsites will also likely
help to increase survival (Rother, et al., 2015). Managers may also
consider different genetic stock than has been used in the past to
increase seedling survival (Chmura, et al., 2011). Tools such as the
Seedlot Selection Tool (https://seedlotselectiontool.org/sst) can help
identify seedling stock that will be best adapted to a given site in
the future.
In general, regeneration in the driest topographic locations may be
slower in a warming climate than it has been in the past. Some areas
are likely to convert from conifer forest to hardwoods or non-forest
(shrubland or grassland) vegetation, particularly at lower treeline.
Managers may need to consider where they will try to forestall change
and where they may need to allow conversions to occur (Rother, et al.,
2015).
Finally, collaboration among many groups-land management agencies,
rural communities, private forest landowners, Tribes, and conservation
groups--is needed for successful adaptation to the effects of a warmer
climate on wildfire (Joyce, et al., 2009; Spies, et al., 2010; Stein,
et al., 2013). Working together will ensure a common vision for
stewardship of forest resources, and help produce a consistent,
effective strategy for fuel treatments and other forest practices
across large forest landscapes.
Uncertainties and future research needs
Changing disturbance regimes will accompany climate change in the
Northwest (Tables 1, 2 and 3). However, uncertainties remain, many
related to future human behavior relative to greenhouse gas emissions,
the rate and magnitude of climate change, and effects on vegetation and
fire regimes. Human activities will also affect fire through land use
and management, fire ignitions, and fire suppression, all of which are
difficult to predict. For example, societal priorities may change,
affecting forest management and vegetation conditions. Fire suppression
is likely to continue in the future, but may become less effective
under more extreme fire weather conditions (Fried, et al., 2008),
affecting area burned.
Historical relationships between climate and fire in the Northwest
indicate that the ENSO and PDO can influence area burned. However, it
is unclear how climate change will affect these modes of climatic
variability or how they may interact with the effects of climate change
on natural resources; global climate models differ in how these cycles
are represented and in how they are projected to change. The frequency
and persistence of high blocking ridges in summer (which divert
moisture from the region) will also affect fire frequency and severity
in the region, and climate change may affect the frequency of these
blocking ridges (Lupo, et al., 1997).
The lack of fire over the last few centuries in forests with low-
frequency and high-severity fire regimes creates uncertainty in fire
projections for the future. Although the likelihood of a large fire
event in these forests is low, if large fire events start occurring as
frequently as some models project (e.g., Rogers, et al., 2011), then
major ecological changes are likely. Updating models as events occur
over time may help to adjust projections in the future.
Shifts in forest productivity and composition are highly likely to
occur with climate change in the region, which could affect fuel
levels. However, it is uncertain how carbon dioxide fertilization will
interact with moisture stress and disturbance regimes to affect forest
productivity (Chmura, et al., 2011) and thus fuel levels. Increased
forest productivity, combined with hot and dry conditions in late
summer, would likely produce large and severe fires (Rogers, et al.,
2011). Continued research on the potential effects of carbon dioxide
fertilization on forest productivity will help to improve fire severity
projections.
Other high-priority research needs include determining forest
ecosystem response to multiple disturbances and stressors (e.g.,
effects of repeated fire and drought on forest regeneration), and
determining post-fire regeneration controls across a range of forest
types and conditions. Identifying locations where vegetation type
shifts (e.g., forest to woodland or shrubland) are likely because of
changing climate and disturbance regimes will help managers determine
where to prioritize efforts. Managers will also benefit from evaluation
of pre- and post-fire forest treatments to increase resilience or
facilitate transition to new conditions in different forest types.
Although this synthesis is focused on the effects of climate change
on fire and vegetation, many secondary effects are expected for natural
resources and ecosystem services, some of which are already occurring.
Climate change is reducing snowpack (Mote, et al., 2018) and affecting
hydrologic function in the Northwest, including more flooding in winter
and lower streamflow in summer (Luce and Holden 2009). Higher stream
temperatures are degrading cold-water fish habitat (Isaak, et al.,
2010). Altered vegetation and snowpack are expected to have long-term
implications for animal habitat (Singleton, et al., 2019). Recreational
opportunities (Hand, et al., 2019), infrastructure on public lands
(Furniss, et al., 2018), and cultural values (Davis 2018) will likely
also be affected by changing climate, fire, and other disturbances.
Uncertainties associated with climate change require an
experimental approach to resource management; using an adaptive
management framework can help address uncertainties and adjust
management over time. In the context of climate change adaptation,
adaptive management involves: (1) defining management goals,
objectives, and timeframes; (2) analyzing vulnerabilities and
determining priorities; (3) developing adaptation options; (4)
implementing plans and projects; and (5) monitoring, reviewing, and
adjusting (Millar, et al., 2014). Scientists and managers can work
together to implement an adaptive management framework and ensure that
the best available science is used to inform management actions on the
ground.
Availability of data and materials
Please contact the corresponding author for data requests.
Acknowledgements
We thank D. Donato, L. Evers, B. Glenn, M. Johnson, V. Kane, M.
Reilly, and three anonymous reviewers for providing helpful suggestions
that improved the manuscript. P. Loesche provided valuable editorial
assistance, J. Ho assisted with literature compilation and figures, and
R. Norheim developed several maps.
Funding
Funding was provided by the U.S. Department of the Interior,
Northwest Climate Adaptation Science Center, and the U.S. Forest
Service Pacific Northwest Research Station and Office of Sustainability
and Climate. None of the funding bodies played any role in the design
of the study, interpretation of data, or writing the manuscript.
Author information
Affiliations
U.S. Department of Agriculture, Forest Service, Pacific Northwest
Research Station, Olympia Forestry Sciences Lab, 3625 93rd Avenue
SW, Olympia, Washington, 98512, USA
Jessica E. Halofsky
School of Environmental and Forest Sciences, College of the
Environment, University of Washington, Box 352100, Seattle,
Washington, 98195-2100, USA
David L. Peterson & Brian J. Harvey
Contributions
J.H. led the study and contributed to information collection,
analysis, and interpretation, and co-wrote the paper. D.P. contributed
to information collection, analysis, and interpretation, and co-wrote
the paper. B.H. contributed to information collection, analysis, and
interpretation, and co-wrote the paper. All authors read and approved
the final manuscript.
Authors' information
J. Halofsky is a research ecologist; D. Peterson is a professor of
forest biology; B. Harvey is an assistant professor of forest ecology.
Corresponding author
Correspondence to Jessica E. Halofsky.
Ethics declarations
Ethics approval and consent to participate
Not applicable.
Consent for publication
Not applicable.
Competing interests
The authors declare that they have no competing interests.
Received: 20 March 2019 Accepted: 11 November 2019.
Published online: 27 January 2020.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional
claims in published maps and institutional affiliations.
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Article 3
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
[https://www.nature.com/articles/nature13179]
Nature
Letter
Increasing CO2 threatens human nutrition
Samuel S. Myers,1, 2 Antonella Zanobetti,\1\ Itai Kloog,\3\
Peter Huybers,\4\ Andrew D.B. Leakey,\5\ Arnold J. Bloom,\6\ Eli
Carlisle,\6\ Lee H. Dietterich,\7\ Glenn Fitzgerald,\8\ Toshihiro
Hasegawa,\9\ N. Michele Holbrook,\10\ Randall L. Nelson,\11\ Michael J.
Ottman,\12\ Victor Raboy,\13\ Hidemitsu Sakai,\9\ Karla A. Sartor,\14\
Joel Schwartz,\1\ Saman Seneweera,\15\ Michael Tausz,\16\ and Yasuhiro
Usui \9\
---------------------------------------------------------------------------
\1\ Department of Environmental Health, Harvard School of Public
Health, Boston, Massachusetts, 02215, USA.
\2\ Harvard University Center for the Environment, Cambridge,
Massachusetts 02138, USA.
\3\ The Department of Geography and Environmental Development, Ben-
Gurion University of the Negev, PO Box 653, Beer Sheva, Israel.
\4\ Department of Earth and Planetary Science, Harvard University,
Cambridge, Massachusetts 02138, USA.
\5\ Department of Plant Biology and Institute for Genomic Biology,
University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA.
\6\ Department of Plant Sciences, University of California at
Davis, Davis, California 95616, USA.
\7\ University of Pennsylvania, Department of Biology,
Philadelphia, Pennsylvania 19104, USA.
\8\ Department of Environment and Primary Industries, Horsham,
Victoria 3001, Australia.
\9\ National Institute for Agro-Environmental Sciences, Tsukuba,
Ibaraki, 305-8604, Japan.
\10\ Department of Organismic and Evolutionary Biology, Harvard
University, Cambridge, Massachusetts 02138, USA.
\11\ United States Department of Agriculture Agricultural Research
Service, Soybean/Maize Germplasm, Pathology, and Genetics Research
Unit, Department of Crop Sciences, University of Illinois, Urbana,
Illinois 61801, USA.
\12\ School of Plant Sciences, University of Arizona, Tucson,
Arizona 85721, USA.
\13\ United States Department of Agriculture Agricultural Research
Service, Aberdeen, Idaho 83210, USA.
\14\ The Nature Conservancy, Santa Fe, New Mexico 87544, USA.
\15\ Department of Agriculture and Food Systems, Melbourne School
of Land and Environment, The University of Melbourne, Creswick,
Victoria 3363, Australia.
\16\ Department of Forest and Ecosystem Science, Melbourne School
of Land and Environment, The University of Melbourne, Creswick,
Victoria 3363, Australia.
Dietary deficiencies of zinc and iron are a substantial global
public health problem. An estimated two billion people suffer these
deficiencies,\1\ causing a loss of 63 million life-years
annually.2, 3 Most of these people depend on C3
grains and legumes as their primary dietary source of zinc and iron.
Here we report that C3 grains and legumes have lower
concentrations of zinc and iron when grown under field conditions at
the elevated atmospheric CO2 concentration predicted for the
middle of this century. C3 crops other than legumes also
have lower concentrations of protein, whereas C4 crops seem
to be less affected. Differences between cultivars of a single crop
suggest that breeding for decreased sensitivity to atmospheric
CO2 concentration could partly address these new challenges
---------------------------------------------------------------------------
to global health.
In the 1990s, several investigators found that elevated atmospheric
CO2 concentration (hereafter abbreviated to
[CO2]) decreased the concentrations of zinc, iron and
protein in grains of wheat,4-7 barley \5\ and rice \8\ grown
in controlled-environment chambers. However, subsequent studies failed
to replicate these results when plants were grown in open-top chambers
and free-air CO2 enrichment (FACE) experiments. A previous
study \9\ found no effect of [CO2] on the concentrations of
zinc or iron in rice grains grown under FACE and suggested that the
earlier findings had been influenced by `pot effects', by which a small
rooting volume led to nutrient dilution at the root-soil interface. Of
the more recent studies,10-13 most have indicated lower
elemental concentrations in soybeans,\10\ sorghum,\10\ potatoes,\11\
wheat \12\ or barley \13\ grown at elevated [CO2], but with
the exception of iron in one study on wheat,\12\ these results were
statistically insignificant, perhaps because of small sample sizes.
Small sample sizes have limited the statistical power of individual
studies of many aspects of plant responses to elevated
[CO2], and metaanalyses involving larger samples of
genotypes, environmental conditions and experimental locations have
been important in resolving which elements of plant function respond
reliably to altered [CO2].14, 15 A recent meta-
analysis of published data concluded that only sulphur is decreased in
grains grown at elevated [CO2].\16\
Here we report findings froma meta-analysis of newly acquired data
from 143 comparisons of the edible portions of crops grown at ambient
and elevated [CO2] fromseven different FACE experimental
locations in Japan, Australia and the United States involving six food
crops (see Table 1). We tested the nutrient concentrations of the
edible portions of rice (Oryza sativa, 18 cultivars), wheat (Triticum
aestivum, eight cultivars), maize (Zea mays, two cultivars), soybeans
(Glycine max, seven cultivars), field peas (Pisum sativum, five
cultivars) and sorghum (Sorghum bicolor, one cultivar). In all, forty-
one genotypes were tested over one to six growing seasons at ambient
and elevated [CO2], where the latter was in the range 546-
586 p.p.m. across all seven study sites. Collectively, these
experiments contribute more than tenfold more data regarding both the
zinc and iron content of the edible portions of crops grown under FACE
conditions than is currently available in the literature. Consistent
with earlier meta-analyses of other aspects of plant function under
FACE conditions.14, 15 we considered the response
comparisons observed from different species, cultivars and stress
treatments and from different years to be independent. The natural
logarithm of the mean response ratio (r = response in elevated
[CO2]/response inambient [CO2]) was used as
themetric for all analyses. Meta-analysis was used to estimate the
overall effect of elevated [CO2] on the concentration of
each nutrient in a particular crop and to determine the significance of
this effect (see Methods).
We found that elevated [CO2] was associated with
significant decreases in the concentrations of zinc and iron in all
C3 grasses and legumes (Fig. 1 and Extended Data Table 1).
For example, wheat grains grown at elevated [CO2] had 9.3%
lower zinc (95% confidence interval (CI) ^12.7% to ^5.9%) and 5.1%
lower iron (95% CI ^6.5% to ^3.7%) than those grown at ambient
[CO2]. We also found that elevated [CO2] was
associated with lower protein content in C3 grasses, with a
6.3% decrease (95% CI ^7.5% to ^5.2%) inwheat grains and a 7.8%
decrease (95% CI ^8.9% to ^6.8%) in rice grains. Elevated
[CO2] was associated with a small decrease in protein in
fieldpeas, and therewas no significant effect in soybeans or
C4 crops (Fig. 1 and Extended Data Table 1).
In addition to our own observations, we obtained data from 10 of 11
previously-published studies investigating nutrient changes in the
edible portion of food crops (Extended Data Table 6) and combined these
data with our own observations in a larger meta-analysis. Analysis of
our results combined with previously published FACE data (Extended Data
Table 2), or combined with previously published data from both FACE and
chamber experiments (Extended Data Table 3), was consistent with the
results obtained using only our new data. Combining our data with
previously published data did not alter the significance or
substantially alter the effect size of the nutrient changes for any
crop or any nutrient.
In addition to nutrient concentrations, we also measured phytate, a
phosphate storage molecule present in most plants that inhibits the
absorption of dietary zinc in the human gut.\17\ We had no a priori
reason to assume that phytate concentrations would change in response
to rising [CO2]. However, formulae for calculating absorbed,
or bioavailable, zinc depend on both the amount of dietary zinc and the
amount of dietary phytate consumed,\17\ making it important to
interpret changes in zinc concentration in the context of possible
changes in phytate. Phytate content decreased significantly at elevated
[CO2] only in wheat (P<0.01). This decrease might offset
some of the declines in zinc for this particular crop, although the
decrease was slightly less than half of the decrease in zinc. For other
crops examined, however, the lack of a concurrent decrease in
phytatemay further exacerbate problemsof zinc deficiency.
Table 1 D Characteristics of agricultural experiments
----------------------------------------------------------------------------------------------------------------
CO2 ambient/
Crops Country Treatments used Years grown Number of Number of elevated
replicates cultivars (p.p.m.)
----------------------------------------------------------------------------------------------------------------
Wheat
Site 1 Australia 2 water levels, 2 2007-2010 4 8 382/546-550
nitrogen treatments,
2 sowing times
Site 2 Australia 1 water level, 1 2007-2009 4 1 382/546-550
nitrogen treatment, 2
sowing times
Field peas Australia 2 water levels 2010 4 5 382/546-550
Rice
Site 1 Japan 1 nitrogen treatment, 2007-2008 3 3 376-379/570-
2 warming treatments 576
Site 2 Japan 3 nitrogen treatments, 2010 4 18 386/584
2 warming treatments
Maize United States 2 nitrogen treatments 2008 4 2 385/550
Soybeans United States 1 treatment 2001, 2002, 4 7 372-385/550
2004, 2006-
2008
Sorghum United States 2 water levels 1998-1999 4 1 363-373/556-
579
----------------------------------------------------------------------------------------------------------------
`Number of replicates' refers to the number of identical cultivars grown under identical conditions in the same
year and location but in separate FACE rings.
The global [CO2] in the atmosphere is expected to reach
550 p.p.m. in the next 40-60 years, even if further actions are taken
to decrease emissions.\18\ At these concentrations, we find that the
edible portions of many of the key crops for human nutrition have
decreased nutritional value when compared with the same plants grown
under identical conditions but at the present ambient [CO2].
Analysis of the United Nations' Food and Agriculture Organization food
balance sheets reveals that in 2010 roughly 2.3 billion people were
living in countries whose populations received at least 60% of their
dietary zinc and/or iron from C3 grains and legumes, and 1.9
billion lived in countries that received at least 70% of one or both of
these nutrients from these crops (Extended Data Table 5). Reductions in
the zinc and iron content of the edible portion of these food crops
will increase the risk of zinc and iron deficiencies across these
populations and will add to the already considerable burden of disease
associated with them.
The implications of decreased protein concentrations in non-
leguminous C3 crops are less clear. From a study of adult
men and women in the United States, there is strong evidence that the
substitution of dietary carbohydrate for dietary protein increased the
risk of hypertension, lipid disorders, and 10 year coronary heart
disease risk.\19\ For the developing world, minimum protein
requirements for different demographic groups are an area of active
research and debate.\20\ For countries such as India, however, inwhich
up to \1/3\ of the rural population is thought to be at risk of not
meeting protein requirements \21\ and in which most protein comes in
the form of C3 grains,\21\ decreased protein content in non-
leguminous C3 crops may have serious consequences for public
health.
Whereas zinc and iron were significantly decreased in all
C3 crops tested, only iron in maize was observed to
decreaseamong the C4 crops. No changes were found in
sorghum. That zinc and iron declines were notable in C3
crops but less so in C4 crops is consistent with differences
in physiology. C4 crops concentrate CO2
internally, which results in photosynthesis being CO2-
saturated even under ambient [CO2] conditions, leading to no
stimulation of photosynthetic carbon assimilation at elevated
[CO2] levels under mesic growing conditions.\22\ Our finding
that protein content was less affected in legumes than in other
C3 crops is also physiologically consistent with the general
ability of leguminous crops to match the stimulation of photosynthetic
carbon gain at elevated [CO2] with greater nitrogen
fixation, to maintain tissue carbon:nitrogen (C:N) ratios.\23\ In
contrast, most temperate non-legume C3 crops are generally
unable to extract and assimilate sufficient nitrogen from soils to
maintain tissue C:N ratios.24, 25
Little is known about the mechanism(s) responsible for the decline
in nutrient concentrations associatedwith elevated [CO2].
Someauthors have proposed `carbohydrate dilution', by which
CO2-stimulated carbohydrate production by plants dilutes the
rest of the grain components.\26\ To test this hypothesis, we measured
concentrations of additional elements for all crops except wheat
(Extended Data Table 4). Our findings were inconsistent with
carbohydrate dilution operating alone. If only passive dilution of
nutrients were occurring, we would have expected to see very similar
changes in the concentration of each nutrient tested for a given crop.
In contrast, we found that elemental changes in the individual crops
are distinct from each other. For example, in rice grains (Extended
Data Table 4) the decrease in zinc concentrations associated with
elevated [CO2] was significantly different from the
decreases in the concentrations of copper (P50.001), calcium (P50.001),
boron (P50.001) and phosphate (P=0.010). This heterogeneous response
was also observed in recent analyses reviewing possible mechanisms for
nutrient changes in both edible and non-edible plant tissues grown at
elevated [CO2].\27\ It also seems that the mechanism(s)
causing these changes operate distinctly in different species. In one
instance, for example, we found boron to be significantly decreased in
soybeans (P50.001), whereas itwas significantly elevated in rice grains
(P50.001). Although these differences may, in part, have derived from
different environmental conditions, they suggest that the
mechanismismore complex than carbohydrate dilution alone. Of all the
elements, changes in nitrogen content at elevated [CO2] have
been themost studied, and inhibition of photorespiration and malate
production,\24\ carbohydrate dilution,\26\ slower uptake of nitrogen in
roots \25\ and decreased transpiration-driven mass flow of nitrogen \7\
may all be significant.
Figure 1 D Percentage change in nutrients at elevated [CO2]
relative to ambient [CO2]
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Numbers in parentheses refer to the number of comparisons in
which replicates of a particular cultivar grown at a specific
site under one set of growing conditions in 1 year at elevated
[CO2] have been pooled and for which mean nutrient
values for these replicates are compared with mean values for
identical cultivars under identical growing conditions except
grown at ambient [CO2]. In most instances, data from
four replicates were pooled for each value, meaning that eight
experiments were combined for each comparison (see Table 1 for
details of experiments). Error bars represent 95% confidence
intervals of the estimates.
Figure 2 D Percentage change (with 95% confidence intervals) in
nutrients at elevated [CO2] relative to ambient
[CO2], by cultivar
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
a, Zinc; b, iron; c, protein.
We also examined the effects of elevated [CO2] on zinc,
iron and protein content as a function of cultivar when data were
available (Fig. 2). Whereas most crops showed negligible differences
across cultivars, concentrations of zinc and iron across rice cultivars
varied substantially (P=0.04 and P=0.03, respectively; Fig. 2a, b).
Such differences between cultivars suggest a basis for breeding rice
cultivars whose micronutrient levels are less vulnerable to increasing
[CO2]. Similar effects may occur in other crops, given that
the statistical power of many of our other intercultivar tests was
limited by sample size. We note, however, that such breeding programmes
will not be a panacea for many reasons including the affordability of
improved seeds and the numerous criteria used by farmers in making
planting decisions that include taste, tradition, marketability,
growing requirements and yield. In addition, as has been noted
previously, there are likely to be trade-offs with respect to yield and
other performance characteristics when breeding for increased zinc and
iron content.\28\
The public health implications of global climate change are
difficult to predict, and we expect many surprises. The finding that
raising atmospheric [CO2] lowers the nutritional value of
C3 food crops is one such surprise that we can now better
predict and prepare for. In addition to efforts to limit increases in
[CO2], it may be important to develop breeding programmes
designed to decrease the vulnerability of key crops to these changes.
Nutritional analysis of which human populations are most vulnerable
todecreased dietary availability of zinc, iron and protein from
C3 crops could help to target response efforts, including
breeding decreased sensitivity to elevated [CO2],
biofortification, and supplementation.
Methods Summary
We examined the response of nutrient levels to elevated atmospheric
[CO2] for the edible portions of rice (Oryza sativa, 18
cultivars), wheat (Triticum aestivum, eight cultivars), maize (Zea
mays, two cultivars), soybeans (Glycine max, seven cultivars), field
peas (Pisum sativum, five cultivars) and sorghum (Sorghum bicolor, one
cultivar). The six crops were grown under FACE conditions; in all six
experiments the elevated [CO2] was in the range 546-586
p.p.m.
In accordance with methods described previously,14, 15
the natural logarithm of the response ratio (r=response in elevated
[CO2]/response in ambient [CO2]) was used as the
metric for analyses and is reported as the mean percentage change
(100 (r^1)) at elevated [CO2]. Consistent with these earlier
analyses of multiple species grown under FACE conditions, the responses
of different species, cultivars and stress treatments and from
different years of the FACE experiments were considered to be
independent and suited to meta-analytic analysis.\14\
The meta-analysis was designed to estimate the effect of elevated
[CO2] on the concentration of each nutrient in a particular
crop and to determine the significance of this effect relative to a
null hypothesis of no change. All tests were conducted as two-sided;
that is, not specifying which direction the nutrient concentrations
were expected to change under elevated [CO2]. Meta-analysis
was conducted with a linear mixed model.
Parameter estimates were obtained by the restricted maximum-
likelihood method, a standard approach for analysing repeated
measurements \29\ that, in our case, were of nutrient concentrations at
the time of harvest. Results for all analyses are reported as the best
estimate of percentage changes in the concentration of nutrients along
with the 95% confidence intervals associated with each estimate. Two-
tailed P values are also reported.
Online Content
Any additional Methods, Extended Data display items and Source Data
are available in the online version of the paper; references unique to
these sections appear only in the online paper.
Received 25 November 2013; accepted 24 February 2014.
Published online 7 May 2014.
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Acknowledgements
We thank L. S. De la Puente, M. Erbs, A. Fangmeier, P. Hogy, M.
Lieffering, R. Manderscheid, H. Pleijel and S. Prior for sharing data
from their groups with us; H. Nakamura, T. Tokida, C. Zhu and S.
Yoshinaga for contributions to the rice FACE project; and M. Hambidge,
W. Willett, D. Schrag, K. Brown, R. Wessells, N. Fernando, J. Peerson
and B. Kimball for reviews of earlier drafts or conceptual
contributions to this project. V.R. thanks A.L. Harvey for her efforts
in producing the phytate data included here. The National Agriculture
and Food Research Organization (Japan) provided the grain samples of
some rice cultivars. We thank the following for financial support of
this work: the Bill & Melinda Gates Foundation; the Winslow Foundation;
the Commonwealth Department of Agriculture (Australia), the
International Plant Nutrition Institute, (Australia), the Grains
Research and Development Corporation (Australia), the Ministry of
Agriculture, Forestry and Fisheries (Japan); the National Science
Foundation (NSF IOS-08-18435); USDA NIFA 2008-35100-044459; research at
SoyFACE was supported by the U.S. Department of Agriculture
Agricultural Research Service; Illinois Council for Food and
Agricultural Research (CFAR); Department of Energy's Office of Science
(BER) Midwestern Regional Center of the National Institute for Climatic
Change Research at Michigan Technological University, under Award
Number DEFC02-06ER64158; and the National Research Initiative of
Agriculture and Food Research Initiative Competitive Grants Program
Grant no. 2010-65114-20343 from the USDA National Institute of Food and
Agriculture. Early stages of this work received support from Harvard
Catalyst The Harvard Clinical and Translational Science Center
(National Center for Research Resources and the National Center for
Advancing Translational Sciences, National Institutes of Health Award
8UL1TR000170-05).
Author Contributions
S.S.M. conceived the overall project and drafted the manuscript.
A.Z., I.K., J.S. and P.H. performed statistical analyses. P.H. and
A.D.B.L. provided substantial input into methods descriptions. A.J.B.,
E.C. and V.R. analysed grain samples for nutrient content. G.F., T.H.,
A.D.B.L., R.L.N., M.J.O., H.S., S.S., M.T. and Y.U. conducted FACE
experiments and supplied grain for analysis. N.M.H. and P.H. assisted
with elements of experimental design. K.A.S. and L.H.D. assisted with
data collection and analysis. All authors contributed to manuscript
preparation.
Author Information
Reprints and permissions information is available at
www.nature.com/reprints. The authors declare no competing financial
interests. Readers are welcome to comment on the online version of the
paper. Correspondence and requests formaterials should be addressed to
S.S.M. ([email protected]).
Methods
We examined the response of nutrient levels to elevated atmospheric
[CO2] for the edible portions of rice (Oryza sativa, 18
cultivars), wheat (Triticum aestivum, eight cultivars), maize (Zea
mays, two cultivars), soybeans (Glycine max, seven cultivars), field
peas (Pisum sativum, five cultivars) and sorghum (Sorghum bicolor, one
cultivar). The six crops were grown under FACE conditions; in all six
experiments, the elevated [CO2] was in the range 546-586
p.p.m. (see the Agricultural Methods section below for details
associated with individual trials).
Statistics. In accordance with methods described
previously,14, 15 the natural logarithm of the response
ratio (r=response in elevated [CO2]/response in ambient
[CO2]) was used as the metric for analyses and is reported
as the mean percentage change (100 (r^1)) at elevated [CO2].
Consistent with these earlier analyses of multiple species grown under
FACE conditions, the responses of different species, cultivars and
stress treatments and from different years of the FACE experiments were
considered to be independent and suited to meta-analytic analysis14.
The meta-analysis was designed to estimate the overall effect of
elevated [CO2] on the concentration of each nutrient in a
particular crop and to determine the significance of this effect
relative to a null hypothesis of no change. All tests were conducted as
two-sided--not specifying which direction the nutrient concentrations
were expected to change under elevated [CO2]--to make the
analysis as general as possible. Meta-analysis was conducted with a
linear mixed model. A random intercept was included for each
comparison, representing nutrient level variability unrelated to
[CO2] that was common to both treatment groups. Additional
analyses indicated that the effect of [CO2] on zinc
concentration in rice was modified by cultivar and amount of nitrogen
application, suggesting systematic variations across the pooled
analysis of rice, and for these samples it was shown that the effect on
zinc concentration was still significant when including interactions
terms for cultivar and nitrogen. No other significant modifications of
the [CO2] effect were identified. We tested whether changes
in different nutrients for particular crops were statistically
different from each other, as has been described.\30\ To address the
issue of multiple comparisons when testing for differences between
cultivars within a crop, we multiplied the P value by the number of
independent comparisons. This approach follows the so-called Bonferroni
correction and is conservative in the sense of biasing the P values
high, but still shows that individual test results are significant
despite their having been selected from multiple tests.
Parameter estimates were obtained by the restricted maximum-
likelihood method, a standard approach for analysing repeated
measurement data \29\ that, in our case, were of nutrient
concentrations at time of harvest. Results for all analyses are
reported as the best estimate of percentage changes in the
concentration of nutrients along with the 95% confidence intervals
associated with each estimate. Two-tailed P values are also reported.
When combining our data with previously published data, we defined
outliers as pairs in which the difference between an observation at
ambient [CO2] and elevated [CO2] was at least
three times the standard deviation from the mean differences for that
crop and nutrient type when calculated using all observations. Using
this criterion, we excluded a total of two pairs of previously
published data fromall analyses; these included one observation of iron
in rice and one observation of zinc in potato.
Agricultural methods. Rice (Oryza sativa, 18 cultivars), wheat
(Triticum aestivum, eight cultivars), maize (Zea mays, two cultivars),
soybeans (Glycine max, seven cultivars), field peas (Pisum sativum,
four cultivars) and sorghum (Sorghum bicolor, one cultivar) were grown
under FACE conditions during daylight hours. The experiments were
conducted in Australia, Japan and the United States between 1998 and
2010. Ambient [CO2] ranges were between 363 and 386 p.p.m.;
elevated [CO2] was between 546 and 584 p.p.m. With the
exception of soybeans, each experiment involveed multiple cultivars of
each crop and more than one set of growing conditions. Each experiment
for each cultivar and set of treatments was replicated four times, with
the exception of one of the rice sites, for which three replicates were
performed. These data are summarized in Table 1, and additional details
of the soil and growing conditions, FACE methods and experimental
designs have been published for rice,\31\ wheat,\32\ maize,\33\
soybeans,\34\ field peas \32\ and sorghum.\35\
Minerals method. Samples were analysed for minerals by heated
closed-vessel digestion/dissolution with nitric acid and hydrogen
peroxide followed by quantification with an inductively coupled plasma
atomic emission spectrometer.\36\ Nitrogen content was measured by
flash combustion of the sample coupled with thermal conductivity/
infrared detection of the combustion gases (N2,
NOX and CO2) with a LECO TruSpec CN Analyzer.\37\
Protein values are based on measurement of nitrogen and conversion to
proteinwith the equation below, where k=5.36 (ref. 38):
protein (weight %)=k nitrogen (weight %)
For phytic acid determination, amodified version of the method of ref.
39 was used. The accuracy of the method was monitored by the inclusion
of tissue standards of known and varying levels of phytic acid.\40\
Dietary calculations. The United Nations Food and Agriculture
Organization (UNFAO) publishes annual Food Balance Sheets, which
provide country-specific data on the quantities of 95 `standardized'
food commodities available for human consumption. Data, expressed in
terms of dietary energy (kilocalories per person per day) were
downloaded for 210 countries and territories with available information
for the period 2003-2007 (available at http://faostat.fao.org). The
percentage of dietary energy available from C3 grasses
(wheat, barley, rye, oats, rice and `cereals, other' (excluding
Eragrostis tef))was calculated globally with estimates weighted by
national population size (188 countries available; UN 2011; 2012
revision available at http://esa.un.org/wpp/).
Dietary intake data from the UNFAO Food Balance Sheets (to year
2000) and food composition data fromtheUnited States Department of
Agriculture National Nutrient Database for Standard Reference were used
to calculate per-person nutrient intake for 95 food items; these were
shared with us with permission.\41\ This data set was used to calculate
the contribution of each food itemto total dietary zinc and iron
intake, and the proportions of all food items derived from
C3 grains and legumes were summed to identify countries that
are highly dependent on plant sources of iron and zinc (Extended Data
Table 5).
30. Schenker, N. & Gentleman, J.F. On judging the significance of
differences by examining the overlap between confidence intervals. Am.
Stat. 55, 182-186 (2001).
31. Hasegawa, T.A., et al. Rice cultivar responses to elevated CO2 at
two free-air CO2 enrichment (FACE) sites in Japan. Funct. Plant Biol.
40, 148-159 (2013).
32. Mollah, M., Norton, R. & Huzzey, J. Australian Grains Free Air
Carbon dioxide Enrichment (AGFACE) facility: design and performance.
Crop Pasture Sci. 60, 697-707 (2009).
33. Markelz, R., Strellner, R. & Leakey, A. Impairment of C4
photosynthesis by drought is exacerbated by limiting nitrogen and
ameliorated by elevated CO2 in maize. J. Exp. Bot. 62, 3235-3246
(2011).
34. Gillespie, K., et al. Greater antioxidant and respiratory metabolism
in field-grown soybean exposed to elevated O3 under both ambient and
elevated CO2. Plant Cell Environ. 35, 169-184 (2012).
35. Ottman, M.J., et al. Elevated CO2 increases sorghum biomass under
drought conditions. New Phytol. 150, 261-273 (2001).
36. Sah, R.N. & Miller, R.O. Spontaneous reaction for acid dissolution
of biological tissues in closed vessels. Anal. Chem. 64, 230-233
(1992).
37. AOAC Official Method 972.43. in Official Methods of Analysis of AOAC
International, 18th edition, Revision 1, 2006 Ch. 12 5-6 (AOAC
International, 2006).
38. Mosse, J. Nitrogen to protein conversion factor for ten cereals and
six legumes or oilseeds. A reappraisal of its definition and
determination. Variation according to species and to seed protein
content. J. Agric. Food Chem. 38, 18-24 (1990).
39. Haug, W. & Lantzsch, H.J. Sensitive method for the rapid
determination of phytate in cereals and cereal products. J. Sci. Food
Agric. 34, 1423-1426 (1983).
40. Raboy, V., et al. Origin and seed phenotype of maize low phytic acid
1-1 and low phytic acid 2-1. Plant Physiol. 124, 355-368 (2000).
41. Wuehler, S.E., Peerson, J.M. & Brown, K.H. Use of national food
balance data to estimate the adequacy of zinc in national food
supplies: methodology and regional estimates. Public Health Nutr. 8,
812-819 (2005).
Extended Data Table 1 D Percentage change in nutrient content at elevated [CO2K] relative to ambient [CO2K]
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Zn (mg/g) Fe (mg/g) Protein (mg/g) Phytate (g/100g)
N * (number --------------------------------------------------------------------------------------------------------------------------------------------------------------------
of pairs) % 95% CI P-value % 95% CI P-value % 95% CI P-value % 95% CI P-value
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
C3 grasses
Wheat...... 64 ^9.3 (^12.7, <.0001 ^5.1 (^6.5, ^3.7) <.0001 ^6.3 (^7.5, ^5.2) <.0001 ^4.2 (^7.5, 0.009
^5.9) ^0.8)
Rice....... 31 ^3.3 (^5.0, ^1.7) <.0001 ^5.2 (^7.6, ^2.9) <.0001 ^7.8 (^8.9, ^6.8) <.0001 1.2 (^4.6, 7.4) 0.697
C3 legumes
Field peas. 10 ^6.8 (^9.8, ^3.8) 0.002 ^4.1 (^6.7, ^1.4) 0.003 ^2.1 (^4.0, ^0.1) 0.039 ^5.8 (^11.5, 0.055
0.1)
Soybeans... 25 ^5.1 (^6.4,^3.9) <.0001 ^4.1 (^5.8,^2.5) <.0001 0.5 (^0.4,1.3) 0.267 ^1.3 (^3.7, 1.2) 0.303
C4 grasses
Maize...... 4 ^5.2 (^10.7, 0.6) 0.077 ^5.8 (^10.9, 0.038 ^4.6 (^13.0,4.5) 0.312 ^6.1 (^15.0, 0.215
^0.3) 3.7)
Sorghum.... 4 ^1.3 (^6.2, 3.8) 0.603 1.6 (^5.8, 9.7) 0.674 0.0 (^4.9, 5.2) 0.993 12.8 (^15.8, 0.418
51.1)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* `Number of pairs' refers to the number of comparisons in which replicates of a particular cultivar grown at a specific site under one set of growing conditions in 1 year at elevated [CO2]
have been pooled and mean nutrient values for these replicates were compared with mean values for identical cultivars under identical growing conditions except grown at ambient [CO2]. In
most instances, data from four replicates were pooled for each value, meaning that eight experiments were combined for each comparison (see Table 1 for details of experiments).
Extended Data Table 2 D Original data combined with previously published FACE data from studies 3, 4, 6 and 7
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Zn (mg/g) Fe (mg/g) Protein (mg/g)
N * (number ----------------------------------------------------------------------------------------------------------------------------
of pairs) % 95% CI P-value % 95% CI P-value % 95% CI P-value
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
C3 grasses
Wheat.............................................. 70 ^8.8 (^11.9, <.0001 ^5.5 (^6.8, ^4.1) <.0001 ^6.5 (^7.5, ^5.4) <.0001
^5.6)
Rice............................................... 32 ^3.1 (^4.8, ^1.5) <.0001 ^4.9 (^7.3, ^2.6) <.0001 ^8 (^9.0, ^6.9) <.0001
Barley............................................. 4 ^11.4 (^19.3, 0.012 ^10.5 (^12.2, <.0001 ^11.9 (^13.1, <.0001
^2.7) ^8.7) ^10.7)
C3 legumes
Field peas......................................... 10 ^6.8 (^9.8, ^3.8) 0.002 ^4.1 (^6.7, ^1.4) 0.003 ^2.1 (^4.0, ^0.1) 0.039
Soybeans........................................... 25 ^5.1 (^6.4, ^3.9) <.0001 ^4.1 (^5.8, ^2.5) <.0001 0.5 (^0.4, 1.3) 0.267
C3 tubers
Potato............................................. 2 ^3.9 (^12.9, 6.2) 0.440 2.3 (^3.8, 8.7) 0.472 ^4.6 (^7.7, ^1.4) <.0001
C4 grasses
Maize.............................................. 4 ^5.2 (^10.7, 0.6) 0.077 ^5.8 (^10.9, 0.038 ^4.6 (^13.0, 4.5) 0.312
^0.3)
Sorghum............................................ 4 ^1.3 (^6.2, 3.8) 0.603 1.6 (^5.8, 9.7) 0.674 0.0 (^4.9, 5.2) 0.993
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
See Extended Data Table 6 for a list of experiments. Percentage change in nutrient content at elevated [CO2] relative to ambient [CO2].
* `Number of pairs' refers to the number of comparisons in which replicates of a particular cultivar grown at a specific site under one set of growing conditions in 1 year at elevated [CO2]
have been pooled and mean nutrient values for these replicates were compared with mean values for identical cultivars under identical growing conditions except grown at ambient [CO2]. In
most instances, data from four replicates were pooled for each value, meaning that eight experiments were combined for each comparison (see Table 1 for details of experiments).
Extended Data Table 3 D Original data combined with previously published FACE and chamber data from studies 1-10
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Zn (mg/g) Fe (mg/g) Protein (mg/g)
N * (number ----------------------------------------------------------------------------------------------------------------------------
of pairs) % 95% CI P-value % 95% CI P-value % 95% CI P-value
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
C3 grasses
Wheat.............................................. 78 ^9.1 (^12.1, <.0001 ^5.9 (^7.8, ^4.0) <.0001 ^7.2 (^8.6,^5.8) <.0001
^6.1)
Rice............................................... 32 ^3.1 (^4.8, ^1.5) <.0001 ^4.9 (^7.3, ^2.6) <.0001 ^8 (^9.0, ^6.9) <.0001
Barley............................................. 6 ^13.6 (^19.3, <.0001 ^10.0 (^12.4, <.0001 ^15.0 (^19.1, <.0001
^7.6) ^7.4) ^10.7)
C3 legumes
Field peas......................................... 10 ^6.8 (^9.8, ^3.8) <.0001 ^4.1 (^6.7, ^1.4) 0.003 ^2.1 (^4.0, ^0.1) 0.039
Soybeans........................................... 28 ^5.0 (^6.1, ^3.9) <.0001 ^5.2 (^7.9, ^2.5) <.0001 0.1 (^0.8, 0.9) 0.865
C3 tubers
Potato............................................. 5 ^10.0 (^20.9, 2.4) 0.110 ^4.1 (^16.6, 0.555 ^9.7 (^15.9, 0.005
10.3) ^3.1)
C4 grasses
Maize.............................................. 4 ^5.2 (^10.7, 0.6) 0.077 ^5.8 (^10.9, 0.038 ^4.6 (^13.0, 4.5) 0.312
^0.3)
Sorghum............................................ 7 ^0.6 (^4.5, 3.4) 0.764 33.8 (^10.2, 0.153 ^5.6 (^12.7, 2.1) 0.150
99.3)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
See Extended Data Table 6 for a list of experiments. Percentage change in nutrient content at elevated [CO2] relative to ambient [CO2].
* `Number of pairs' refers to the number of comparisons in which replicates of a particular cultivar grown at a specific site under one set of growing conditions in 1 year at elevated [CO2]
have been pooled and mean nutrient values for these replicates were compared with mean values for identical cultivars under identical growing conditions except grown at ambient [CO2]. In
most instances, data from four replicates were pooled for each value, meaning that eight experiments were combined for each comparison (see Table 1 for details of experiments).
Extended Data Table 4 D Percentage change in nutrient content at elevated [CO2K] compared with ambient [CO2K] for all nutrients
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
C3 grasses C3 legumes C4 grasses
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Wheat Rice Field Peas Soybean Maize Sorghum
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
% 95% CI P-value % 95% CI P-value % 95% CI P-value % 95% CI P-value % 95% CI P-value % 95% CI P-value
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Zinc (ppm) ^9.3 (^12.7, <.0001 ^3.3 (^5.0, ^1.7) <.0001 ^6.8 (^9.8, ^3.8) <.0001 ^5.1 (^6.4, ^3.9) <.0001 ^5.2 (^10.7, 0.6) 0.077 ^1.3 (^6.2, 3.8) 0.603
^5.9)
Iron (ppm) ^5.1 (^6.5, ^3.7) <.0001 ^5.2 (^7.6, ^2.9) <.0001 ^4.1 (^6.7, ^1.4) <.0001 ^4.1 (^5.8, ^2.5) <.0001 ^5.8 (^10.9, 0.038 1.6 (^5.8, 9.7) 0.674
^0.3)
Phytate (mg/g) ^4.2 (^7.5, ^0.8) 0.009 1.2 (^4.6, 7.4) 0.7 ^5.8 (^11.5, 0.1) 0.055 ^1.3 (^3.7, 1.2) 0.303 ^6.1 (^15.0, 3.7) 0.215 12.8 (^15.8, 0.418
51.1)
Protein ^6.3 (^7.5, ^5.2) <.0001 ^7.8 (^8.9, ^6.8) <.0001 ^2.1 (^4.0, ^0.1) 0.039 0.5 (^0.4, 1.3) 0.267 ^4.6 (^13.0, 4.5) 0.312 0.0 (^4.9, 5.2) 0.993
Mn (ppm) ^7.5 (^12.0, <.0001 ^2.5 (^4.2, ^0.8) 0.005 ^1.4 (^3.5, 0.8) 0.204 ^4.2 (^10.5, 2.5) 0.215 1.7 (^4.5, 8.3) 0.596
^2.8)
Mg (%) ^0.9 (^2.3, 0.6) 0.24 0.0 (^1.3, 1.4) 0.960 ^3.5 (^4.3, ^2.8) <.0001 ^5.7 (^9.9, ^1.3) 0.011 ^0.2 (^5.1, 4.9) 0.944
Cu (ppm) ^10.6 (^13.8, <.0001 ^2.7 (^5.1, ^0.3) 0.025 ^5.7 (^8.0, ^3.4) <.0001 ^9.9 (^19.3, 0.7) 0.066 ^2.9 (^7.1, 1.5) 0.190
^7.1)
Ca (%) 2 (^0.8, 4.9) 0.16 ^0.5 (^4.2, 3.3) 0.787 ^5.8 (^7.3, ^4.2) <.0001 ^2.7 (^16.9, 0.734 11.2 (^5.2, 30.3) 0.190
13.9)
S (ppm) ^7.8 (^8.8, ^6.8) <.0001 ^2.2 (^3.6, ^0.7) 0.003 ^2.9 (^3.5, ^2.2) <.0001 2.1 (^2.2, 6.7) 0.342 ^0.2 (^5.4, 5.2) 0.936
K (%) 1.1 (^0.3, 2.5) 0.13 2.2 (0.6, 3.8) 0.008 0.1 (^0.8, 1.0) 0.857 ^2.7 (^3.1, ^2.2) <.0001 3.0 (^2.7, 9.1) 0.308
B (ppm) 5.1 (1.9, 8.4) 0.002 ^1.9 (^3.9, 0.1) 0.057 ^6.4 (^9.1, ^3.6) <.0001 4.9 (^1.0, 11.1) 0.107 ^0.3 (^9.3, 9.6) 0.952
P (%) ^1.0 (^2.4, 0.4) 0.160 ^3.7 (^6.8, ^0.5) 0.023 ^0.7 (^2.2, 0.9) 0.379 ^7.1 (^9.0, ^5.1) <.0001 0.3 (^4.0, 4.9) 0.881
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sample sizes for each crop type are identical to those listed in Table 1.
Extended Data Table 5 D Countries whose populations receive at least 60%
of dietary iron and/or zinc from C3 grains and legumes
------------------------------------------------------------------------
% Iron from C3 % Zinc from C3
Country grains & grains & Population
legumes legumes (in thousands)
------------------------------------------------------------------------
Afghanistan 78% 78% 31,412
Algeria 76% 79% 35,468
Iraq 74% 83% 31,672
Bangladesh 72% 88% 148,692
Iran, Islamic Rep. of 72% 77% 73,974
Pakistan 70% 72% 173,593
Tunisia 70% 77% 10,481
Jordan 69% 73% 6,187
Morocco 69% 78% 31,951
Syrian Arab Republic 67% 71% 20,411
Libya 67% 71% 6,355
Yemen 66% 75% 24,053
Myanmar 65% 81% 47,963
Tajikistan 62% 56% 6,879
India 59% 71% 1,224,614
Egypt 54% 65% 81,121
Indonesia 52% 65% 239,871
Sierra Leone 51% 70% 5,868
Cambodia 49% 68% 14,138
Sri Lanka 46% 69% 20,860
Laos 44% 66% 6,201
Viet Nam 43% 61% 87,848
---------------
Total............... 2,329,612
------------------------------------------------------------------------
Source: United Nations Food and Agriculture Organization food balance
sheets and 2010 United Nations estimated population.
Extended Data Table 6 D Literature reporting nutrient changes in the
edible portion of crops grown at elevated and ambient [CO2]
------------------------------------------------------------------------
Study Experimental Method Associated Citations
------------------------------------------------------------------------
1 Growth Chambers Conroy, J., Seneweera, S.P.,
Basra, A., Rogers, G. & Nissen-
Wooller, B. Influence of rising
atmospheric CO2 concentrations
and temperature on growth,
yield and grain quality of
cereal crops. Australian
Journal of Plant Physiology 21,
741-758 (1994).
Seneweera, S., Milham, P. &
Conroy, J. Influence of
elevated CO2 and phosphorus
nutrition on the growth and
yield of a short-duration rice.
Australian Journal of Plant
Physiology 21, 281-292 (1994).
Seneweera, S.P. & Conroy, J.P.
Growth, grain yield and quality
of rice (Oryza sativa L.) in
response to elevated CO2 and
phosphorus nutrition (Reprinted
from Plant nutrition for
sustainable food production and
environment, 1997). Soil Sci.
Plant Nutr. 43, 1131-1136
(1997).
2 Temperature Gradient Tunnels De la Puente, L.S., Perez, P.P.,
Martinez-Carrasco, R.,
Morcuende, R.M. & Del Molino,
I.M.M. Action of elevated CO2
and high temperatures on the
mineral chemical composition of
two varieties of wheat.
Agrochimica 44, 221-230 (2000).
3 Open Top Chambers & FACE De Temmerman L., et al. Effect
of climatic conditions on tuber
yield (Solanum tuberosum L.) in
the European `CHIP'
experiments. European Journal
of Agronomy 17, 243-255 (2002).
De Temmerman, L., Hacour, A. &
Guns, M. Changing climate and
potential impacts on potato
yields and quality `CHIP':
introduction, aims and
methodology. European Journal
of Agronomy 17, 233-242 (2002).
Fangmeier, A., De Temmerman, L.,
Black, C., Persson, K. & Vorne,
V. Effects of elevated CO2 and/
or ozone on nutrient
concentrations and nutrient
uptake of potatoes. European
Journal of Agronomy 17, 353-368
(2002).
Hogy, P. & Fangmeier, A.
Atmospheric CO2 enrichment
affects potatoes: 2. Tuber
quality traits. European
Journal of Agronomy 30, 85-94
(2009).
4 FACE Erbs, M., et al. Effects of free-
air CO2 enrichment and nitrogen
supply on grain quality
parameters and elemental
composition of wheat and barley
grown in a crop rotation.
Agriculture, Ecosystems and
Environment 136, 59-68 (2010).
5 Open Top Chambers Fangmeier, A., et al. Effects of
elevated CO2, nitrogen supply
and tropospheric ozone on
spring wheat. I. Growth and
yield. Environmental Pollution
91, 381-390 (1996).
Fangmeier, A., Gruters, U.,
Hogy, P., Vermehren, B. &
Jager, H.-J. Effects of
elevated CO2, nitrogen supply
and tropospheric ozone on
spring wheat--II. Nutrients (N,
P, K, S, Ca, Mg, Fe, Mn, Zn).
Environmental Pollution 96, 43-
59 (1997).
Fangmeier, A., et al. Effects on
nutrients and on grain quality
in spring wheat crops grown
under elevated CO2
concentrations and stress
conditions in the European,
multiple-site experiment
'ESPACE-wheat'. European
Journal of Agronomy 10, 215-229
(1999).
Jager, H.-J., Hertstein, U. &
Fangmeier, A. The European
Stress Physiology and Climate
Experiment--project 1: wheat
(ESPACE-wheat): introduction,
aims and methodology. European
Journal of Agronomy 10, 155-162
(1999).
6 FACE Hogy, P. & Fangmeier, A. Effects
of elevated atmospheric CO2 on
grain quality of wheat. Journal
of Cereal Science 48, 580-591
(2008).
Hogy, P., et al. Does elevated
atmospheric CO2 allow for
sufficient wheat grain quality
in the future?. Journal of
Applied Botany and Food Quality
82, 114-121 (2009).
Hogy, P., et al. Effects of
elevated CO2 on grain yield and
quality of wheat: results from
a 3-year free-air CO2
enrichment experiment. Plant
Biology 11, 60-69 (2009).
Hogy, P., Zorb, C.,
Langenkamper, G., Betsche, T. &
Fangmeier, A. Atmospheric CO2
enrichment changes the wheat
grain proteome. Journal of
Cereal Science 50, 248-254
(2009).
7 FACE Kim , H., Lieffering, M., Miura,
S., Kobayashi, K. & Okada, M.
Growth and nitrogen uptake of
CO2-enriched rice under field
conditions. New Phytologist
150, 223-229 (2001).
Kim, H., et al. Effects of free-
air CO2 enrichment and nitrogen
supply on the yield of
temperate paddy rice crops.
Field Crops Research 83, 261-
270 (2003).
Lieffering, M., Kim, H.-Y.,
Kobayashi, K. & Okada, M. The
impact of elevated CO2 on the
elemental concentrations of
field-grown rice grains. Field
Crops Research 88, 279-286
(2004).
8 Open Top Chambers Pleijel, H., et al. Effects of
elevated carbon dioxide, ozone
and water availability on
spring wheat growth and yield.
Physiologia Plantarum 108, 61-
70 (2000).
Pleijel, H. & Danielsson, H.
Yield dilution of grain Zn in
wheat grown in open-top chamber
experiments with elevated CO2
and O3 exposure. Journal of
Cereal Science 50, 278-282
(2009).
9 Open Top Chambers Prior, S.A., Runion, G.B.,
Rogers, H.H., Torbert, H.A.
Effects of atmospheric CO2
enrichment on crop nutrient
dynamics under no-till
conditions. Journal of Plant
Nutrition 31, 758-773 (2008).
10 Open Top Chambers Weigel, H., Manderscheid, R.,
Jager, H.-J. & Mejer, G.
Effects of season-long CO2
enrichment on cereals. I.
Growth performance and yield.
Agriculture, Ecosystems and
Environment 48, 231-240 (1994).
Manderscheid, R., Bender, J.,
Jager, H.-J. & Weigel, H.J.
Effects of season long CO2
enrichment on cereals. II.
Nutrient concentrations and
grain quality. Agriculture,
Ecosystems & Environment 54,
175-185 (1995).
11 FACE Yang, L., Wang, Y., Dong, G.,
Gu, H., Huang, J., Zhu, J.,
Yang, H., Liu, G., Han, Y. The
impact of free-air CO2
enrichment (FACE) and nitrogen
supply on grain quality of
rice. Field Crops Research 102,
128-140 (2007).
Meta-Analyses Loladze, I. Rising atmospheric
CO2 and human nutrition: toward
globally imbalanced plant
stoichiometry? Trends in
Ecology and Evolution 17 (10),
457-461 (2002). [Uses data from
studies 1, 2, 5, and 10 as well
as numerous other studies on
non-edible tissues and plants
other than food crops].
McGrath, J.M. and Lobell, D.B.
Reduction of transpiration and
altered nutrient allocation
contribute to nutrient decline
of crops grown in elevated CO2
concentrations. lant, Cell, &
Environment 36, 697-705 (2013).
[Uses data from studies 1, 5,
and 10 as well as numerous
other studies on non-edible
tissues and plants other than
food crops].
Duval, B.D., Blankinship, J. C.,
Dijkstra, P., Hungate, B. A.
CO2 effects on plant nutrient
concentration depend on plant
functional group and available
nitrogen: a meta-analysis.
Plant Ecology 213, 505-521
(2012). [Uses data from studies
1, 2, 3, 5, 6, and 9 as well as
numerous other studies on non-
edible tissues and plants other
than food crops].
------------------------------------------------------------------------
Article 4
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
[https://www.nature.com/articles/s41467-020-20678-z]
Nature
Communications
Over half of western United States' most abundant tree species in
decline
Hunter Stanke,1, 2, * Andrew O. Finley,1, 3 Grant
M. Domke,\4\ Aaron S. Weed \5\ & David W. MacFarlane \1\
---------------------------------------------------------------------------
\1\ Department of Forestry, Michigan State University, East
Lansing, MI, USA.
\2\ School of Environmental and Forest Sciences, University of
Washington, Seattle, WA, USA.
\3\ Department of Geography, Environment, and Spatial Sciences,
Michigan State University, East Lansing, MI, USA.
\4\ Forest Service, Northern Research Station, U.S. Department of
Agriculture, St. Paul, MN, USA.
\5\ Northeast Temperate Inventory and Monitoring Network, U.S.
National Park Service, Woodstock, VT, USA.
* email: [email protected].
---------------------------------------------------------------------------
Abstract
Changing forest disturbance regimes and climate are driving
accelerated tree mortality across temperate forests. However, it
remains unknown if elevated mortality has induced decline of tree
populations and the ecological, economic, and social benefits they
provide. Here, we develop a standardized forest demographic index and
use it to quantify trends in tree population dynamics over the last 2
decades in the western United States. The rate and pattern of change we
observe across species and tree size-distributions is alarming and
often undesirable. We observe significant population decline in a
majority of species examined, show decline was particularly severe,
albeit size-dependent, among subalpine tree species, and provide
evidence of widespread shifts in the size-structure of montane forests.
Our findings offer a stark warning of changing forest composition and
structure across the western U.S., and suggest that sustained
anthropogenic and natural stress will likely result in broad-scale
transformation of temperate forests globally.
Introduction
Persistent shifts in forest composition, structure, and function
depend largely on the demographic response of trees to changing
environmental drivers and disturbance regimes.1, 2 Across
temperate forests--representing 25% of the world's forested land area
\3\--recent reports of increasing tree mortality have been attributed
to complex interactions among climate, native insects and pathogens,
and uncharacteristically severe wildfire.4, 5, 6 Such
pervasive changes in tree population dynamics can have substantial
impacts on the ecosystem services provided by temperate forests,
including carbon storage and sequestration,\7\ climate regulation,\8\
and provisioning of drinking water.\9\ Sustained anthropogenic and
natural stress is thus expected to result in broad-scale transformation
of temperate forests and the services they provide.10, 11 As
such, a key challenge for ecological research is to quantify the
patterns and underlying drivers of changing tree populations to better
inform forest management and help ease ecological transitions.\12\
Tree demographic rates (e.g., mortality) are important, widely used
indicators of forest health.\12\ However, tree demographic rates are
confounded by stand development processes (i.e., stand aging)
13, 14 and do not yield a comprehensive depiction of tree
population dynamics when considered individually (i.e., the net result
of growth, recruitment, and mortality processes; tree abundance
shifts).15, 16, 17 Thus, while recent reports of elevated
tree mortality are suggestive of broad-scale changes in the composition
and structure of temperate forests,4, 5, 18 such conclusions
should not be accepted in the absence of information regarding tree
recruitment, growth, and stand development.1, 19 Previous
efforts to quantify trends in tree population dynamics have often
relied on observations from old forests to minimize the influence of
stand development processes.5, 18 Still, patterns of tree
population dynamics observed in old forests are seldom characteristic
of those in younger forests \20\ and are thus unlikely to be
representative of patterns emerging across forest landscapes (or
forested regions) that are composed of a mosaic of stands in various
stages of development.\21\ As such, advancement in detection and
prediction of forest health decline depends largely on the
dissemination of methods that comprehensively describe tree population
dynamics and account for variation in tree demography arising from
stand development processes.14, 19
To this end, we propose the forest stability index (FSI), a direct
measure of temporal change in relative live tree density that is
independent of stand development processes by design. Temporal change
in absolute tree density (e.g., trees per hectare (TPH)) emerges from
the joint demographic response of tree populations to endogenous (e.g.,
inter-tree competition) and exogenous drivers (e.g., wildfire).\22\
That is, change in absolute tree density is the net result of
mortality, growth, and recruitment processes, and is thus a
demographically comprehensive measure of tree population dynamics.
Relative tree density may be defined as the proportion of absolute tree
density observed in a stand relative to the maximum theoretical density
the stand could achieve given its observed tree size-distribution. The
maximum density that a population of trees may achieve is expected to
decline as individuals grow in size, following well-established
allometric scaling laws that drive stand development processes (i.e.,
self-thinning).15, 16, 17, 23, 24 Indices of relative tree
density (i.e., ratio of observed and maximum theoretical tree density)
are thus independent of stand development processes by definition, as
allometric tree size-density relationships are explicitly acknowledged
in their denominator.
The FSI is defined as the change in relative density observed in a
population of trees over time (e.g., via remeasurement of forest
inventory plots). Here stability is achieved when the relative density
of a tree population is constant (e.g., FSI equal to zero, stand
remains at 50% stocking over time), despite underlying changes in
absolute tree density and size distribution. Stability in this sense is
uncommon at the stand-scale, as stands progress toward maximum relative
density in the absence of exogenous stress (positive FSI, e.g., tree
growth exceeds mortality) and relative density is expected to decline
given disturbance (negative FSI, e.g., disturbances act as thinning
agents). At the landscape-scale, however, stability represents a
balance between disturbance and tree growth processes, and deviations
from this dynamic equilibrium may be indicative of pervasive changes in
forest structure, composition, and function.
We use the FSI to identify patterns in relative tree density shifts
of the eight most abundant tree species in the western United States
(U.S.) and determine the importance of major forest disturbances in
driving the population dynamics of each species over the last 2
decades. Many forests in the western U.S. have experienced recent
increases in the extent, severity, and frequency of
wildfire,25, 26 drought,27, 28 and insect-pest
outbreaks,29, 30 owing in part to changing climate and past
forest management (i.e., fire suppression). Likewise, large-scale tree
mortality events 5, 31 and recruitment failures
32, 33 indicate that widespread forest change is already
underway in the region. Such issues are not, however, unique to forests
of the western U.S. Increased disturbance activity has been documented
in other regions of the temperate biome in recent
decades,12, 34, 35 and the broad spatial and climatic domain
encompassed by the western U.S. suggests that patterns of forest change
observed herein may be highly relevant to temperate forests across the
globe.
We draw upon over 24,000 repeated censuses of U.S. Forest Service
Forest Inventory and Analysis (FIA) plots to address the following
questions: (1) What is the current status of populations of the eight
most abundant tree species in the western U.S. (i.e., expanding,
declining), and what do inter-specific differences in the rate of
relative tree density shifts indicate about changes in forest
composition? (2) Is the rate of relative tree density shifts size-
dependent, and if so, what do these relationships indicate about
changes in forest structure? (3) Does the rate of relative tree density
shifts vary across space within species ranges, and what are the
general patterns of change for each species? (4) How do major forest
disturbances influence the populations of these dominant species, and
what do these relationships suggest about species sensitivity to future
changes in forest disturbance regimes?
Here, we show a majority of the most abundant tree species in the
western U.S. experienced significant population decline over the last 2
decades. Further, we show the magnitude of change in tree populations
diverges strongly across species, species-size distributions, and
species ranges, and the patterns of such change are generally
inconsistent with broad-scale reversion of forests toward historical
conditions. Altogether, we provide empirical evidence of widespread,
yet spatially varying, changes in forest composition and structure over
the last 2 decades in the western U.S.
Results
We identified the eight most abundant tree species in the western
U.S. by their estimated total number of live stems (i.e., diameter
%2.54 cm at 1.37 m above ground) across the region (Fig. 1). Top
species represented six distinct genera and three families (Table 1).
We categorized species by general ecosystem associations, including two
woodland species (i.e., characteristic of mid-high-elevation desert/
steppe), three subalpine species (i.e., commonly occurring in cool,
moist high-elevation forests), and three montane species (i.e.,
characteristic of mid-elevation forests climatically bounded by
woodland (hotter, drier) and subalpine ecosystems (cooler, wetter)).
Together these top eight species accounted for 61.6% of all live trees
across the study region (62.3% of total live basal area).
Fig. 1: Study area colored by ecoregion divisions
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Ecoregion divisions are differentiated by broad-scale
patterns of precipitation and temperature. Our study area spans
both the humid and dry domains of the western U.S. We exclude
the state of Wyoming due a lack of data.
Table 1
------------------------------------------------------------------------
Scientific Ecosystem No.
Common name name association Prevalence plots
------------------------------------------------------------------------
Douglas-fir Pseudotsuga Montane 0.15 12,284
menziesii
Mirb.
Lodgepole Pinus contorta Subalpine 0.11 4556
pine Doug.
Subalpine Abies Subalpine 0.09 3174
fir lasiocarpa
Hook.
Ponderosa Pinus Montane 0.06 7309
pine ponderosa
Doug.
Common Pinus edulis Woodland 0.05 3076
pinyon Engelm.
Quaking Populus Montane 0.05 1723
aspen tremuloides
Michx.
Engelmann Picea Subalpine 0.05 3079
spruce Engelmannii
Parry
Utah Juniperus Woodland 0.04 3446
juniper osteosperma
Torr.
------------------------------------------------------------------------
Scientific and common names of the eight most abundant tree species
across the western U.S., listed in order of decreasing prevalence
(i.e., the proportion of total number of stems represented by each
species across the region).
Commonly accepted ecosystem associations are reported for each species
along with their respective sample size in the FIA plot network
(remeasured plots only).
The FSI is defined as the average annual change in the relative
density of a population of live trees, or the ratio of observed tree
density to maximum potential tree density given site conditions and
observed tree size-distributions. Hence, significant positive values of
the FSI indicate increased relative density (i.e., population
expansion), significant negative values indicate decreased relative
density (i.e., population decline), and values of the FSI not
significantly different from zero indicate population stability (i.e.,
no change in relative density). Herein, we treat changes in population
range boundaries and within-range density shifts as functionally
equivalent processes. For example, range expansion (population
occurrence on a site where it was previously absent) is represented by
the FSI as a positive change in relative density (i.e., where previous
relative density is zero). Thus, when summarized across broad spatial
domains the FSI represents a comprehensive measure of the net
performance of a population of trees during the temporal frame of
sampling (i.e., in terms of net changes in relative abundance).
Broad-scale shifts in forest composition and structure
Species-level estimates of the mean FSI across the entire study
region (i.e., range-average estimates) reveal broad-scale patterns of
rapid change in the composition of western U.S. forests (over 91
million hectares of forestland) over the last 2 decades (Fig. 2). Three
of the eight most abundant species in the region (lodgepole pine,
Engelmann spruce, and quaking aspen) exhibited average decreases in
relative density (i.e., population decline) at rates exceeding 1% per
year over the 18 year study period (2001-2018), whereas Douglas-fir
increased in relative density at nearly the same rate. For reference, a
%FSI equal to 1% is equivalent to an 18% change in relative density
over the duration of the study period. Across all species, population
decline occurred more frequently (five of eight of species) and with
greater magnitude (Fig. 2; leftward skew) than population expansion.
Fig. 2: Range-average % forest stability index (FSI) of the eight most
abundant tree species in the western U.S. over the period 2001-
2018
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Population decline (red) occurs when the FSI is negative and
the associated 95% confidence interval does not include zero.
Conversely, population expansion (blue) occurs when the FSI is
positive and the associated confidence interval does not
include zero. Here, the %FSI is a direct measure of average
annual percent change in the relative density of each species
across their ranges in the western U.S. Thus, total % change in
relative density can be estimated by multiplying the %FSI by
the length of the study period (18 years). For reference,
complete loss of a species over the study period would be
indicated by a %FSI value of ^5.56%. Source data are provided
as a Source Data file.
Severe rates of population decline were apparent in all three
subalpine species considered herein, with lodgepole pine and Engelmann
spruce exhibiting the highest rates of decline among all species
(lodgepole pine approaching decline of 2% annually, 36% over the entire
study period). Douglas-fir and ponderosa pine, both montane species,
exhibited the highest rates of range-wide population expansion. In
contrast, quaking aspen populations declined at a rate exceeding the
rate of expansion observed in other montane species. Woodland species
exhibited the highest degree of population stability (range-average
mean FSI values closest to zero) over the last 2 decades, although low
rates (<0.20% annually, 3.6% over the duration of the study period) of
population expansion and decline were observed for Utah juniper and
common pinyon, respectively.
Variation in range-average estimates of the FSI across species-size
distributions are indicative of extensive, complex shifts in the size-
structure of forests of the western U.S. over the period 2001-2018
(Fig. 3). Rapid population decline was evident in nearly all size-
classes of subalpine tree species (except the smallest 10% of subalpine
fir and lodgepole pine). Further, the rate of population decline
appeared to increase with increasing tree size across all subalpine
species (Fig. 3; downward trend in FSI), and this trend was most severe
in lodgepole pine (largest 20% of trees declined at rates exceeding 3%
annually, 54% over the duration of the study period). The opposite
pattern appeared for Douglas-fir and ponderosa pine, where the largest
trees generally outperformed the smallest trees of each species (i.e.,
higher or more positive changes in relative density).
Fig. 3: Range-average % forest stability index (FSI) across size
distributions of the eight most abundant tree species in the
western U.S. over the period 2001-2018
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Population decline (red) occurs when the FSI is negative and
the associated confidence interval does not include zero.
Conversely, population expansion (blue) occurs when the FSI is
positive and the associated confidence interval does not
include zero. Here, the %FSI is a direct measure of average
annual percent change in the relative density of each species
across their ranges in the western U.S., and variation in the
FSI across species-size distributions is indicative of shifts
in forest structure during the study period. Total % change in
relative density can be estimated by multiplying the %FSI by
the length of the study period (18 years), with a maximum
annual decline of ^5.56% (complete loss of the population over
the study period). Source data are provided as a Source Data
file.
Interestingly, population decline was evident among the smallest
size-classes of Douglas-fir (lower 20%) and ponderosa pine (lower 50%),
whereas the largest size-classes of both species exhibited population
expansion. Patterns of change in relative density across the size-
distribution of quaking aspen appeared to follow an approximately
quadratic trend, with population expansion evident in the smallest and
largest 10% of stems and severe population decline (approaching 3%
annually, 54% over the duration of the study period) apparent near the
median (50%) tree size class. The size distribution of woodland species
(i.e., common pinyon and Utah juniper) appeared to be the most stable
of all species examined, indicated by relatively low variation in
relative density shifts across tree size-classes (Fig. 3; nearly flat
trends).
Early indications of shifting species distributions
Summaries of the FSI within ecoregion divisions revealed broad-
scale spatial patterns of change in the relative density of each
species over the last 2 decades in the western U.S. (Fig. 4b).
Population decline was spatially pervasive among all subalpine species
and particularly severe for lodgepole pine in the mountain temperate
steppe division (i.e., central and northern Rocky Mountains). Though
interestingly, lodgepole pine populations increased in relative density
(i.e., population expansion) in the mountain marine (i.e., coastal
Pacific Northwest) and mountain Mediterranean (i.e., Sierra Nevada)
divisions over the study period. Quaking aspen exhibited consistent
rates of population decline across its range within the study region
( 1% annually, 18% over the duration of the study period). Spatial
patterns of relative density shifts of Douglas-fir and ponderosa pine
were similar, with decline evident for both species in the mountain
subtropical steppe division (i.e., southern Rocky Mountains) and
expansion in the northwestern portion of the study region (particularly
strong for Douglas-fir in the marine and mountain marine divisions). In
contrast, we found general patterns of population stability across the
ranges of both woodland species, with the majority of each species'
range characterized by FSI values near zero.
Fig. 4: Spatial variation in the % forest stability index (%FSI) of
eight most abundant species across their ranges in the western
U.S. over the period 2001-2018
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Mean %FSI values are mapped at two spatial scales: ecoregion
subsection a and ecoregion division b. Boundaries of the study
region are outlined in black, and white areas within the study
area indicate absence of a species in the FIA plot network
(i.e., colored regions represent species' ranges). For
reference, ecoregion division boundaries (as seen in Fig. 1)
are outlined as gray dotted lines, and maps of the %FSI within
ecoregion divisions (bottom) have been clipped to the extent of
each species' range (i.e., defined by ecoregion subsections
where the species was detected on an FIA plot). Tree
populations have been observed to expand in areas characterized
by positive FSI estimates (blue), and decline in areas
characterized by negative %FSI estimates (red) during the
inventory period (approximately 2 decades). For reference, %FSI
values ^2% indicate a 36% decline in relative density over the
duration of the study period. Source data are provided as a
Source Data file.
While the general spatial patterns of the FSI observed in
subsection-level summaries (Fig. 4a) mirrored those of division-level
summaries, subsection-level summaries revealed patterns of change in
species relative density at finer spatial scales than division-level
summaries. Qualitatively, the FSI appears to exhibit strong, positive
spatial auto-correlation across ecoregion subsections, and such local-
scale variation is not well represented in division-level summaries.
Specifically, local regions of population expansion and regions of
population decline (i.e., consisting of multiple adjoining ecoregion
subsections with similar FSI values) emerge to varying degrees within
the range of each species. However, spatial patterns of population
performance were not always consistent among overlapping species,
indicating shifts in local-scale forest composition.
Forest disturbances as drivers of relative tree density shifts
Estimated effects of forest disturbances on relative density
highlight disturbances as important drivers of tree population dynamics
in the western U.S., though the magnitude of disturbance effects varied
strongly by tree species and disturbance type (Fig. 5). Here, we
present effects of forest disturbances as percent change in relative
tree density estimated to be caused by each disturbance type at the
population-level (i.e., product of disturbance severity and disturbance
probability). Hence, high magnitude of estimated effects indicates a
disturbance type is an important driver of the population dynamics of a
tree species (e.g., Fig. 5, insect outbreaks in lodgepole pine).
Fig. 5: Posterior distributions of the estimated effects of forest
disturbances on the relative density of live tree populations
for the eight most abundant species in the western U.S. over
the period 2001-2018
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Change in relative tree density resulting from each
disturbance type is estimated as the product of average
disturbance severity and probability (annual), where
disturbance severity is defined as the average difference in
relative density shifts between undisturbed and disturbed
sites. Posterior probability distributions of parameters are
estimated via Markov chain Monte Carlo (5,000 samples).
Posterior medians of each parameter are plotted as black
vertical lines. Asterisks indicate the 95% credible interval of
the mean effect excludes zero, and hence are considered
statistically significant. Source data are provided as a Source
Data file.
Across all species, fire and insect outbreaks generally emerged as
more important drivers (i.e., larger estimated effects) of relative
density shifts than disease (Fig. 5), although the effects of disease
exceeded those of fire and insects for quaking aspen. In most cases,
disturbance was negatively associated with changes in relative density,
however estimated effects of disease were positive in Engelmann spruce
and lodgepole pine over the study period. Disturbance effects appeared
to be most severe (i.e., highest magnitude, exceeding 0.2% annually)
among subalpine species, where insect outbreaks were determined to be
dominant drivers of relative density shifts in Engelmann spruce and
lodgepole pine, and fire was of heightened importance for subalpine
fir. Fire also emerged as the most important disturbance type affecting
the relative density of Douglas-fir and ponderosa pine, both montane
species. The effects of disturbance appeared to be least severe among
Utah juniper and common pinyon, relative to other species (<0.1%
annually).
Discussion
Complex interactions between changing climate, forest disturbance
regimes, and past forest management (e.g., fire suppression) are
driving accelerated change in tree demography in temperate
forests.4, 5, 36 However, a great deal of uncertainty
remains regarding the net result of such demographic change and its
consequences for forest composition and structure across broad spatial
domains1. Herein, we develop the FSI, a standardized demographic index
that weights observed changes in live tree density and tree size
against those expected given well-established allometric size-density
relationships in forests. We then apply the FSI to over 24,000
remeasured forest inventory plots in the western U.S. to quantify
recent trends in tree population dynamics in the region. Our results
indicate a majority of the most abundant tree species in the western
U.S. experienced significant population decline over the period 2001-
2018 (five of eight species, representing 60.7% of all stems of study
species), where population decline is indicated by a net decrease in
relative live tree density (i.e., negative FSI). Furthermore, we found
strong divergence in the magnitude of change in relative tree density
across species (Fig. 2), species-size distributions (Fig. 3), and
species ranges (Fig. 4). Such dramatic variation in relative density
shifts provides empirical evidence of broad-scale, yet spatially
varying, changes in forest composition and structure over the last 2
decades in the western U.S.
Importantly, the current composition and structure of many forests
types in the western U.S. differ drastically from their historic range
of variability, arising as a legacy of widespread fire suppression
(early 20th century to present day) and intensive harvesting (19th to
early 20th century).\37\ Novel forest conditions (e.g., abundance of
high density, closed-canopy forests dominated by fire-intolerant
species) have interacted with changing climate to incite rapid
increases in disturbance activity in the western U.S. and other regions
of the temperate biome.29, 34 At face-value, it is therefore
not inherently surprising to observe a net decrease in the relative
density of many top tree species in the western U.S., as disturbances
act as natural thinning agents in tree populations. However, the
examination of patterns in live tree density shifts across species
ranges and size-distributions offers a sobering line of evidence that
is inconsistent with broad-scale reversion of forests toward historical
conditions. Instead, our results support the following general trends
in western U.S. forests over the last 2 decades: (1) severe, spatially
pervasive decline of subalpine forests coinciding with density shifts
towards smaller tree size-classes; (2) broad-scale expansion of large-
diameter montane conifers and decline of small-diameter conspecifics;
and (3) net population stability of woodland species.
The rate of population decline we observed in subalpine species is
particularly severe (comprising 25.3% of all trees in the western
U.S.). Over the duration of the 18 year study period, the relative
density of lodgepole pine declined 32.2% (R0.05%) across its range in
the western United States, while Engelmann spruce and subalpine fir
declined 21.3% (R0.05%) and 13.2% (R0.04%) across their respective
ranges, respectively (Fig. 2). Decline appears spatially pervasive at
broad scales across the study region (ecoregion divisions), however
local regions of intense population decline and expansion emerge at
finer spatial scales (ecoregion subsections) for all subalpine species
(Fig. 4). Such patterns may indicate the primary drivers of subalpine
tree population dynamics operate at sub-regional scales, likely
responding to local-scale variation in climate, topoedaphic conditions,
and disturbance history.\37\ Previous studies have indicated that
subalpine tree species are among the most vulnerable to future changes
in climate and forest disturbance regimes.38, 39, 40 Our
results indicate this heightened vulnerability is already manifesting
across the western U.S., serving as an early warning of potentially
widespread, rapid decline of subalpine forests in other regions of the
temperate biome.
Interestingly, we show that severity of population decline
increased with tree size for each subalpine species during the study
period (Fig. 3). That is, population decline was most severe among the
largest trees of each species. This result adds to an increasing body
of evidence, suggesting that large, old trees are at high risk of
decline in forests across the globe.\41\ Large, old trees generally
occur at low density but are of high ecological significance,
influencing the rates and patterns of regeneration and succession,
moderating microclimate and water use, and contributing
disproportionately to forest biomass and carbon cycling at a global
scale.\42\ Hence, the rapid decline of large-diameter trees we observe
in subalpine tree species of the western U.S. is of grave concern and
may foreshadow broad-scale transformation in the structure and
ecological function of subalpine forests.
In addition, we found population decline to be pervasive across all
but the smallest size-classes of subalpine species (Fig. 3). Hence, our
results indicate that subalpine forests of the western U.S. have, on
average, become younger and thinner over the last 2 decades. Of all
species examined herein, the size-density distributions of subalpine
fir and Engelmann spruce are arguably the most likely to exist within
their historic range of variability as both species tend to occur in
cool, moist forests characterized by infrequent stand-replacing fires
(i.e., effects of fire suppression are marginal relative to dry
forest).\43\ The pervasive, size-dependent decline we observe in
subalpine fir and Engelmann spruce is thus particularly concerning,
indicating the size-distribution of each species may be beginning to
depart from historically stable conditions. In contrast, decades of
fire suppression and intensive harvesting in the western U.S. have
resulted in an overabundance of mature, homogeneous lodgepole pine
forest that is highly susceptible to native insect outbreaks.\37\ As
such, reversion to historical conditions would require an increase in
heterogeneity in the size-distribution of lodgepole pine at the
landscape-level. Instead, the size-dependent patterns of decline we
observe in lodgepole pine is indicative of increased homogeneity in the
species' size-distribution, where small-diameter stems have become
increasingly common relative to large-diameter stems despite a decline
in relative tree density across nearly all tree size-classes (younger,
thinner, more structurally homogeneous forests).
Our results further indicate that insect outbreaks were >2.5 times
more important than other disturbance types in driving relative density
shifts of lodgepole pine and Engelmann spruce over the study period
(Fig. 5), likely linked to recent outbreaks of mountain pine beetle
(Dendroctonus ponderosae),\44\ and spruce beetle (Dendroctonus
rufipennis),\45\ respectively. As both mountain pine beetle and spruce
beetle have shown preference for large hosts (i.e., large-diameter
trees), heightened insect-pest activity may explain size-dependent
patterns of decline in lodgepole pine and Engelmann spruce. In
contrast, we determined wildfire to be more than three times more
important than other disturbance types in driving relative density
shifts of subalpine fir (Fig. 5), and recent increases in the extent
and frequency of wildfire 25, 46 could potentially explain
size-dependent decline observed in the species. Specifically, increases
in fire probability (and disturbance probability more generally) are
likely to coincide with reduced mean stand age \21\ and subsequent
decline in populations of large trees across a landscape.
Interestingly, we found the relative density of lodgepole pine and
Engelmann spruce increase, on average, in response to disease
outbreaks, opposite their response to other disturbance types. We argue
this result may arise from inter-specific compensatory responses to
host-specific pathogens and/or mortality complexes. That is, one
species may benefit from the targeted mortality of a competing species
within a stand. It is likely that diseases affecting quaking aspen
(e.g., sudden aspen decline \47\) and subalpine fir (e.g., subalpine
fir decline \48\) may result in a positive growth response of competing
lodgepole pine and Engelmann spruce, thereby increasing their relative
density within affected stands.
We observed the highest rates of range-average population expansion
in Douglas-fir (17.1%R0.02 over the study period) and ponderosa pine
(6.9%R0.03 over the study period; Fig. 2), widespread montane conifers
that together represent 21.2% of all trees across the western U.S. It
is important to note the population expansion observed for Douglas-fir
and ponderosa pine may not be desirable in many settings, particularly
in dry forests where both species occur frequently as canopy
dominants49,50. Across the western U.S., decades of fire exclusion have
created overstocked stand conditions that increase the probability of
high-severity disturbance (i.e., wildfire, insect outbreak)
51, 52 and may degrade forest resilience.\37\ In many cases,
management aims to reduce tree density via stand thinning and fuels
reduction. Hence high rates of relative density increases observed in
Douglas-fir and ponderosa pine in the interior Pacific Northwest and
portions of the Rocky Mountain region (Fig. 4), may be of substantial
concern to forest managers. In contrast, patterns of decreased relative
density of ponderosa pine and Douglas-fir observed in the Southern
Rocky Mountains may be indicative of tree populations shifting nearer
historic relative densities (Fig. 4).
Divergence in both sign and magnitude of relative density shifts
across size-distributions of ponderosa pine and Douglas-fir is
indicative of broad-scale shifts in the structure of montane coniferous
forests in the western U.S. Specifically, a peak in population
expansion is evident among the 50-75th percentile of tree size-classes
in both species, and potentially arises as a legacy of widespread
logging during the 19th and early 20th century (i.e., owing to
simultaneous maturation of stands across a broad spatial domain).\51\
Furthermore, population decline in the smallest size classes of
Douglas-fir and ponderosa pine may potentially be linked to heightened
wildfire activity during the study period,\46\ as fire was more than
twice as important than other disturbance types in driving change in
relative density in Douglas-fir, and more than five times as important
in ponderosa pine (Fig. 5). That is, increased wildfire activity may
have contributed to desirable change in the structure of montane
coniferous forests (i.e., reduced relative density of small trees) over
the last 2 decades in the western U.S., underscoring the potential for
fire (both managed fire and wildfire) to foster forest resilience and
contribute to restoration efforts in fire-adapted forests.\53\
We found that large-diameter populations of Douglas-fir and
ponderosa pine outperformed (i.e., exhibited higher positive change in
relative density) small-diameter populations of the same species
between 2001 and 2018 in the western U.S. (Fig. 3), opposite the
pattern observed in subalpine species. In fact, we observed significant
expansion among the largest-diameter populations of both species across
the region. This surprising result contradicts previously described
patterns of global decline of large-diameter trees,\41\ suggesting that
such patterns may vary strongly across species and ecosystem
associations in temperate forests (e.g., subalpine vs. montane
ecosystems). Yet, pervasive increases in the relative density of medium
and large-diameter montane conifers may be highly undesirable in some
settings. Specifically, the structure of many dry, fire prone forest
types of the western U.S. have shifted towards dense, closed-canopy
stand conditions that are highly susceptible to crown fire and
outbreaks of native insect and pathogens.\52\ As Douglas-fir and
ponderosa pine are common canopy dominants in dry forest types, our
results may indicate that such systems have diverged further from their
historic natural range of variability over the last 2 decades.
Elevated rates of population decline were evident for quaking aspen
during the study period, pervasive across the range of the species
(Fig. 4) and across its size-distribution (Fig. 3) in the western U.S.
It is not inherently surprising to observe population decline in
quaking aspen given recent spikes in mortality associated with sudden
aspen decline.47, 54 However, the rate of population decline
observed herein is particularly severe (20.2%R0.04% over the 18 year
study period) and serves as a useful baseline to assess the performance
of other species. Notably, the rates of range-average decline observed
for Engelmann spruce and lodgepole pine exceed that of quaking aspen.
Population decline of quaking aspen has received substantial attention
in the forest ecology literature,54, 55, 56 however decline
of Engelmann spruce has received far less. The disproportionate focus
on quaking aspen decline in the literature (and lack of focus on other
declining species), emphasizes the need for large-scale, comprehensive
assessments of changes in forest composition and structure in the
western U.S. and temperate forests elsewhere.
We found woodland species (i.e., Utah juniper and common pinyon) to
exhibit the highest degree of population stability across their ranges
in the western U.S., relative to other top species. Pinyon-juniper
woodlands of the southwestern U.S., where both Utah juniper and common
pinyon occur as dominant species,\50\ have experienced dramatic
expansions in tree density and equally dramatic tree mortality events
over the past century.57, 58 However, inadequate
understanding of historic disturbance regimes and tree population
dynamics of pinyon-juniper woodlands make it difficult to conclude if
such changes are beyond their natural range of variation.\57\ It is
important to note that our results do not preclude such striking change
at spatial and/or temporal domains not addressed herein. Rather, our
results indicate the net responses of Utah juniper and common pinyon
populations are relatively stable across broad spatial domains
(species' ranges) and a relatively short period of time (18 years).
The development of methods to quantify the joint demographic
response of tree populations to novel environmental and anthropogenic
stressors is among the most important advances required to improve
predictions of future change in forest composition, structure, and
function, and hence inform the management of forest ecosystem
services.14, 19, 59 Herein, we present the FSI as one such
method. The FSI is a standardized index of temporal change in relative
live tree density that can be applied in forests of any community and
or structural type. Specifically, the FSI weights observed changes in
live tree density (e.g., absolute change in tree abundance) and tree
size (e.g., tree basal area) against those expected under allometric
size-density laws.16, 17 Hence, although most common indices
of forest change (e.g., mortality rate) are confounded by transient
dynamics in tree demography arising from metabolic scaling and density-
dependent mortality,15, 16, 20 the FSI is independent of
these transient dynamics by design. As such, the FSI may yield simple,
accurate measures of shifts in the structure and composition of forests
when other common indices of forest change cannot.
The simplicity, flexibility, and highly informative nature of the
FSI make it well suited for application in a wide range of ecological
settings, and we expect the index to be applied in similar studies to
assess broad-scale changes in forest composition and structure in other
forested regions across the globe. The FSI relies on temporally
replicated data (i.e., ideally from a large number of samples) to
derive inference of forest change, however the form of data required by
the index are quite simple. For example, all estimates presented herein
were derived from basic measures of tree density (e.g., TPH), tree size
(e.g., diameter at breast height; DBH), and binary codes indicating the
presence or absence of disturbance at measurement sites. As such, the
FSI is uniquely well suited for applications using data collected in
large-scale National Forest inventories. To this end, we provide a
flexible implementation of the FSI in the publicly available R package,
rFIA60, for application of the index using data collected by the U.S.
Forest Service FIA program.
Increased disturbance activity has been documented across temperate
forests in recent decades,12, 34, 35 and forests of the
western U.S. are no exception.29, 46 As disturbances modify
forest structure and regulate tree population dynamics,\21\ our
observation of recent broad-scale shifts in relative tree density
across the western U.S. is not inherently surprising. However, the rate
and pattern of change we observe across species, species-size
distributions, and species ranges is alarming and in many cases
undesirable. Furthermore, results of our efforts to quantify the
importance of major forest disturbances in driving change in tree
populations provide a unique opportunity to assess the vulnerability of
tree species to sustained shifts in forest disturbance regimes, as
expected under global climate change.2, 12 Importantly, the
temporal frame of this study (18 years) is relatively short given the
long life-spans of many tree species in the western U.S. (i.e.,
individuals may live for multiple hundreds of years). As such, it is
unclear how the patterns of change we observe herein will translate to
long-term trends in forest dynamics in the region, highlighting an
important challenge for future research. Nevertheless, our results
offer an early warning of recent, widespread change in forest
composition and structure across the western U.S., and suggest that
sustained anthropogenic and natural stress are likely to result in
broad-scale change of temperate forests globally.
Methods
Field observations
Since 1999, the FIA program has operated an extensive, nationally
consistent forest inventory designed to monitor changes in forests
across all lands in the U.S.\61\ We used FIA data from ten states in
the continental western U.S. (Washington, Oregon, California, Idaho,
Montana, Utah, Nevada, Colorado, Arizona, and New Mexico) to quantify
shifts in relative live tree density, excluding Wyoming due to a lack
of repeated censuses (Fig. 1). This region spans a wide variety of
climatic regimes and forest types, ranging from temperate rain forests
of the coastal Pacific Northwest to pinyon-juniper woodlands of the
interior southwest.\62\ Although the spatial extent of the FIA plot
network represents a large portion of the current range of all species
examined in this study (Table 1), substantial portions of some species
ranges (e.g., Douglas-fir) extend beyond the study region into Canada
and/or Mexico and therefore were not fully addressed here.
The FIA program measures forest attributes on a network of
permanent ground plots that are systematically distributed at a rate of
1 plot per 2,428 hectares across the U.S.\61\ For trees, 12.7 cm DBH
and larger, attributes (e.g., species, DBH, live/dead) are measured on
a cluster of four 168 m\2\ subplots.\61\ Trees 2.54-12.7 cm DBH are
measured on a microplot (13.5 m\2\) contained within each subplot, and
rare events such as very large trees are measured on an optional
macroplot (1012 m\2\) surrounding each subplot.\61\ In the event a
major disturbance (i.e., >1 acre in size, resulting in mortality or
damage to >25% of trees) has occurred between measurements on a plot,
FIA field crews record the primary disturbance agent (e.g., fire) and
estimated year of the event. In the western U.S., \1/10\ of ground
plots are measured each year, with remeasurements first occurring in
2011. Please see Data Availability for more information on forest
inventory data accessibility.
Forest stability index
Allometric relationships between size and density of live trees
make it difficult to interpret many indices of forest change.\19\ Live
tree density is expected to decline as trees grow in size, owing to
increased individual demand for resources and growing space (i.e.,
competition).16, 23 The expected magnitude of change in tree
density, given some change in average tree size, varies considerably
across forest communities,\63\ site conditions,\64\ and stand age
classes.\23\ Thus, we posit it is useful to contextualize observed
changes in live tree density relative to those expected given shifts in
average tree size within a stand. To this end, we developed the FSI, a
measure of change in relative live tree density that can be applied in
stands of any forest community and/or structural type.
To compute the FSI, we first develop a model of maximum size-
density relationships for tree populations in our study system (Fig.
6). This model describes the theoretical maximum live tree density
(Nmax; in terms of tree number per unit area) attainable in
stands as a function of their average tree size (S) and will be used as
a reference curve to determine the proportionate live tree density of
observed stands (i.e., observed density with respect to theoretical
maximum density). We use average tree basal area as an index of tree
size (one, however, could also use biomass, volume, or other indices of
tree size). For stand-type i, the general form of the maximum tree
size-density relationship is given by
where a is a scaling factor that describes the maximum tree density
at S=1 and r is a negative exponent controlling the decay in maximum
tree density with increasing average tree size. Such allometric size-
density relationships (i.e., power functions) are widely accepted as
quantitative law describing the behavior of even-aged plant populations
under self-thinning conditions,16, 17 and have been used
extensively to describe relative stand density in
forests.23, 24 As detailed below, we allow both a and r to
vary with stand-type i, as maximum size-density relationships have been
shown to vary across forest communities and ecological settings.63, 65
Allowing a and r to vary by forest community type, for example, allows
us to acknowledge that the maximum tree density attainable in a
lodgepole pine stand is likely to differ from that of a pinyon-juniper
stand with the same average tree size.
Fig. 6: Maximum size-density relationship for an example stand-type
Individual points represent observed stand-level indices of
tree density (N) and average tree size (S). Maximum tree
density (Nmax) is modeled as a power function of
average tree size within a stand. Here, we use quantile
regression to estimate Nmax as the 99th percentile
of N conditional on S. The resulting maximum size-density curve
can then be used to compute the relative density of observed
stands (RD), where relative density is defined as ratio of
observed tree density (N) to maximum theoretical density
(Nmax), given S. Source data are provided as a
Source Data file.
We next define an index of the relative density of a population of
trees j (e.g., species, Pinus edulis) within a stand of type i (e.g.,
forest community type, pinyon/juniper woodland)
where N is the density represented by tree h (in terms of tree number
per unit area), and S is an index of individual-tree size (e.g., basal
area, as used here). The denominator of Equation (2) represents the
maximum tree density attainable in a stand of type i with average tree
size equal to the size of tree h. We therefore express the relative
density of a population j within stand-type i as a sum of the relative
densities represented by individual trees within the stand. RD can be
interpreted as the proportionate density, or stocking, of a population
of trees within stand, where values range from 0 (population j is not
present within a stand) to 1 (population j constitutes 100% of a stand
and the stand is at maximum theoretical density given its size
distribution). As we do in this study, one may apply any range of
estimators to summarize the expected relative density of a population
of trees j across a range of different stand-types (e.g., estimate the
mean and variance of RDj across a broad region containing
many different stand-types).
It is important to note that Equation (2) is approximately equal to
a simpler
method using aggregate indices (i.e., when tree size-
distributions are nor-
mally distributed (even age-structures). However, the use of aggregate
indices introduces class aggregation bias that results in
overestimation of relative density in stands with non-normal size
distributions (i.e., uneven age-structures), consistent with other
indices of relative tree density.\66\ In contrast, summing tree-level
relative densities eliminates such bias and allows RD to accurately
compare density conditions across stands in very different structural
settings (e.g., even-aged plantation vs. irregularly structured old
forest). Furthermore, the partitioning of relative density into tree-
level densities allows RD to be accurately summarized within tree size-
classes.\66\ That is, it is possible to explicitly estimate the
contribution of tree size-classes to overall stand density using RD.
For a given population j within stand-type i, we define the FSI as
the average annual change in relative tree density observed between
successive measurements of a stand
where Dt is the number of years between successive measurement times
t1 and t2 and DRD is the change in RD over Dt
(i.e., RDt2-RDt1). The FSI may also be expressed
in units of percent change (%FSI), where average annual change in
relative tree density is standardized by previous relative density
Here, stability is defined by zero net change in relative tree
density over time (i.e., FSI equal to zero), but does not imply zero
change in absolute tree density or tree size distributions. For
example, a population exhibiting a decrease in absolute tree density
(e.g., trees per unit area) may be considered stable if such decline is
offset by a compensatory increase in average tree size. However,
populations exhibiting expansion (i.e.,
RDt12) or decline (i.e.,
RDt1>RDt2) in relative tree density will be
characterized by positive and negative FSI values, respectively.
Statistical analysis
We computed the FSI for all remeasured FIA plots in the western
U.S. (N = 24,229). We included plots on both public and private lands
and considered all live stems (DBH %2.54 cm) in our analysis. As forest
management can effect regional shifts in tree density, we excluded
plots with evidence of recent (i.e., within 5 years of initial
measurement) silvicultural treatment (e.g., harvesting, artificial
regeneration, site preparation). All plot measurements occurred from
2001 to 2018, with an average remeasurement interval of 9.78 years
(R0.005 years). For brevity, we restricted our analysis to consider the
eight most abundant tree species in the western U.S. We identified the
most abundant tree species using the rFIA R package,\60\ defining
abundance in terms of estimated total number of trees (DBH %2.54 cm) in
the year 2018. We excluded species that exhibit non-tree growth habits
(i.e., shrub, subshrub) across portions of the study region. All
statistical analysis was conducted in Program R (4.0.0).\67\
We developed a Bayesian quantile regression model to estimate
maximum size-density relationships for stand-types observed within our
study area. Here, we use TPH as an index of absolute tree density,
average tree basal area (BA; equivalent to tree basal area per hectare
divided by TPH) as an index of average tree size, and forest community
type to describe stand-types. We produced stand-level estimates of TPH
and BA from the most recent measurements of FIA plots that (1) lack
evidence of recent (within remeasurement period or preceding 5 years)
disturbance and/or silvicultural treatment and (2) exhibit
approximately normal tree diameter distributions (i.e., even-aged).
Here we define an approximately normal tree diameter distribution as
exhibiting Pearson's moment coefficient of skewness between ^1 and 1.
We transform the nonlinear size-density relationship to a linear
function by taking the natural logarithm of TPH and BA, and use a
linear quantile mixed-effects model to estimate the 99th percentile of
TPH conditional on BA (i.e., in log-log space) for all observed forest
community types. We allowed both the model intercept and coefficient to
vary across observed forest community types (i.e., random slope/
intercept model), thereby acknowledging variation in the scaling factor
(a) and exponent (r) of the maximum tree size-density relationship
across stand-types. We place informative normal priors on the model
intercept (m=7, s=1) and coefficient (m=0.8025, s=0.1) following the
results of decades of previous research in maximum tree size-density
relationships.16, 23, 63, 65
The FIA program uses post-stratification to improve precision and
reduce non-response bias in estimates of forest variables,\68\ and we
used these standard post-stratified estimators to estimate the mean and
variance of the FSI for each species across their respective ranges
within the study area (see Code Availability for all relevant code).
Further, the FIA program uses an annual panel system to estimate
current inventories and change, where inventory cycles consist of
multiple panels, and individual panels are comprised of mutually
exclusive subsets of ground plots measured in the same year within a
region. Precision of point and change estimates can often be improved
by combining annual panels within an inventory cycle (i.e., by
augmenting current data with data collected previously). We used the
simple moving average estimator implemented in the rFIA R package \60\
to compute estimates from a series of eight annual panels (i.e., sets
of plots remeasured in the same year) ranging from 2011 to 2018. The
simple moving average estimator combines information from annual panels
with equal weight (i.e., irrespective of time since remeasurement),
thereby allowing us to characterize long-term patterns in relative
density shifts. We determine populations to be stable if the 95%
confidence intervals for range-averaged FSI included zero.
Alternatively, if confidence intervals of range-averaged FSI do not
include zero, we determine the population to be expanding when the
estimate is positive and declining when the estimate is negative.
To identify changes in species-size distributions, we used the
simple moving average estimator to estimate the mean and variance of
the FSI by species and size class across the range of each species
within our study area. We assign individual trees to size-classes
representing 10% quantiles of observed diameter distributions (i.e.,
diameter at 1.37 m above ground) of each species growing on one of
seven site productivity classes (i.e., inherent capacity of a site to
grow crops of industrial wood). That is, we allow size class
definitions to vary among species and along a gradient of site
productivity, thereby acknowledging intra-specific variation in
diameter distributions arising from differences in growing conditions.
The use of quantiles effectively standardizes absolute size
distributions, simplifying both intra-specific and inter-specific
comparison of trends in relative density shifts along species-size
distributions.
We assessed geographic variation in species relative density shifts
at two scales: ecoregion divisions and subsections.\69\ Ecoregion
divisions (shown for our study area in Fig. 1) are large geographic
units that represent broad-scale patterns in precipitation and
temperature across continents. Ecoregion subsections are subclasses of
ecoregion divisions, differentiated by variation in climate,
vegetation, terrain, and soils at much finer spatial scales than those
represented by divisions. We again used the simple moving average
estimator to estimate the mean and variance of the FSI by species
within each areal unit (i.e., drawing from FIA plots within each areal
unit to estimate mean and variance of the FSI). As a direct measure of
changes in relative tree density, spatial variation in the FSI is
indicative of spatial shifts in species distributions during the
remeasurement interval (i.e., range expansion/contraction and/or
within-range relative density shifts). That is, the distribution of
populations shift toward regions increasing in relative density and
away from regions decreasing in relative density during the temporal
frame of sampling. We map estimates of the FSI for each areal unit to
assess spatial patterns of changes in relative density and identify
regions where widespread geographic shifts in species distributions may
be underway.
We sought to quantify the average effect of forest disturbance
processes on changes in the relative density of top tree species in the
western U.S. over the interval 2001-2018. To this end, we developed a
hierarchical Bayesian model to determine the average severity and
annual probability of disturbances (i.e., wildfire, insect outbreak,
and disease) on sites where each species occurs. Average severity was
modeled as
where yjk is the FSI of species j on plot k, aj
is a species-specific intercept, bjl is a species-specific
coefficient corresponding to the binary variable xlk that
takes the value of 1 if disturbance l occurred within plot k
measurement interval and 0 otherwise. The intercept and regression
coefficients each received an uninformative normal prior distribution.
The species-specific residual standard deviation wj received
a uninformative uniform prior distribution.\70\
On average, disturbance will occur at the midpoint of plot
remeasurement periods, assuming temporal stationarity in disturbance
probability over the study period. As plots in this study are
remeasured on 10 year intervals, we assume that tree populations have,
on average, 5 years to respond to any disturbance event. Hence, our
definition of disturbance severity, bjl's, cannot be
interpreted as the immediate change in relative tree density resulting
from disturbance. Rather, disturbance severity (as defined here)
includes the immediate effects of disturbance, as well as 5 years of
change in relative tree density prior to and following disturbance
(where disturbance is assumed to be functionally instantaneous).
Annual probability of disturbance l on plot k was modeled as
where Dtk is the number of years between successive
measurements of plot k, viewed here as the number of binomial
``trials,'' and cjl is the species-specific probability for
disturbance which was assigned a beta(1,1) prior distribution. Hence,
annual probability of disturbance is assumed to vary by species j and
by disturbance type l.
We estimate the mean effect of forest disturbance processes on
changes in species-specific relative tree density by multiplying the
posterior distributions of bjl and cjl. That is,
we multiply species-specific disturbance severity by disturbance
probability to yield an estimate of the mean change in relative density
caused by disturbance over the study period. We then standardize these
values across species by dividing by the average relative density of
each species at the beginning of the study period. Thus, standardized
values can be interpreted as the annual proportionate change in the
relative tree density of each species resulting from disturbance over
the period 2001-2018.
Reporting summary
Further information on research design is available in the Nature
Research Reporting Summary (https://www.nature.com/articles/s41467-020-
20678-z#MOESM2) linked to this article.
Data availability
All forest inventory data used herein are publicly available in
comma-delimited text format via the USDA Forest Service FIA data
repository (https://apps.fs.usda.gov/fia/datamart/CSV/
datamart_csv.html). Source data are provided with this paper.
Code availability
We have implemented computational routines for the FSI in the
publicly available R package, rFIA.\60\ In addition, all custom code
used herein is publicly available in the following permanent GitHub
repository: https://github.com/hunter-stanke/Code-repository---NCOMMS-
20-20430.
Received: 20 May 2020; Accepted: 1 December 2020; Published online:
19 January 2021.
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Acknowledgements
This work was supported by: National Science Foundation grants DMS-
1916395, EF-1253225, EF-1241874; U.S. Department of Agriculture, Forest
Service, Region 9, Forest Health Protection, Northern Research Station;
U.S. National Park Service; and Michigan State University
AgBioResearch. The findings and conclusions in thispublication are
those of the author(s) and should not be construed to represent any
official U.S. Department of Agriculture or U.S. Government
determination or policy.
Author information
Affiliations
Department of Forestry, Michigan State University, East Lansing,
MI, USA
Hunter Stanke, Andrew O. Finley & David W. MacFarlane
School of Environmental and Forest Sciences, University of
Washington, Seattle, WA, USA
Hunter Stanke
Department of Geography, Environment, and Spatial Sciences,
Michigan State University, East Lansing, MI, USA
Andrew O. Finley
Forest Service, Northern Research Station, U.S. Department of
Agriculture, St Paul, MN, USA
Grant M. Domke
Northeast Temperate Inventory and Monitoring Network, U.S. National
Park Service, Woodstock, VT, USA
Aaron S. Weed
Contributions
H.S., A.O.F., G.M.D., A.S.W., and D.W.M. designed research; H.S.
performed research; H.S. analyzed data; H.S., A.O.F., G.M.D., A.S.W.,
and D.W.M. wrote and reviewed the manuscript.
Corresponding author
Correspondence to Hunter Stanke.
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
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The Author(s) 2021.
Article 5
[https://advances.sciencemag.org/content/4/5/eaaq1012]
Science Advances
Research Article
Carbon dioxide (CO2) levels this century will alter the
protein, micronutrients, andvitamin content of rice grains with
potential health consequences for the poorest rice-dependent
countries
Chunwu Zhu,\1\ Kazuhiko Kobayashi,\2\ Irakli Loladze,\3\ Jianguo
Zhu,\1\ Qian Jiang,\1\ Xi Xu,\1\ Gang Liu,\1\ Saman Seneweera,\4\
Kristie L. Ebi,\5\ Adam Drewnowski,\6\ Naomi K. Fukagawa,\7\ Lewis H.
Ziska \8\ *
---------------------------------------------------------------------------
\1\ State Key Laboratory of Soil and Sustainable Agriculture,
Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008,
P.R. China.
\2\ University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657,
Japan.
\3\ Bryan College of Health Sciences, Bryan Medical Center,
Lincoln, NE 68506, USA.
\4\ Centre for Crop Health, University of Southern Queensland,
Toowoomba, Queensland 4350, Australia.
\5\ Center for Health and the Global Environment (CHanGE),
University of Washington, Seattle, WA 98198, USA.
\6\ Center for Public Health Nutrition, University of Washington,
Seattle, WA 98195, USA.
\7\ U.S. Department of Agriculture-Agricultural Research Service
(USDA-ARS), Beltsville Human Nutrition Center, Beltsville, MD 20705,
USA.
\8\ USDA-ARS, Adaptive Cropping Systems Laboratory, Beltsville, MD
20705, USA.
* Corresponding author. Email: [email protected].
---------------------------------------------------------------------------
Abstract
Declines of protein and minerals essential for humans, including
iron and zinc, have been reported for crops in response to rising
atmospheric carbon dioxide concentration, [CO2]. For the
current century, estimates of the potential human health impact of
these declines range from 138 million to 1.4 billion, depending on the
nutrient. However, changes in plant-based vitamin content in response
to [CO2] have not been elucidated. Inclusion of vitamin
information would substantially improve estimates of health risks.
Among crop species, rice is the primary food source for more than two
billion people. We used multiyear, multilocation in situ FACE (free-air
CO2 enrichment) experiments for 18 genetically diverse rice
lines, including Japonica, Indica, and hybrids currently grown
throughout Asia. We report for the first time the integrated
nutritional impact of those changes (protein, micronutrients, and
vitamins) for the ten countries that consume the most rice as part of
their daily caloric supply. Whereas our results confirm the declines in
protein, iron, and zinc, we also find consistent declines in vitamins
B1, B2, B5, and B9 and, conversely, an increase in vitamin E. A strong
correlation between the impacts of elevated [CO2] on vitamin
content based on the molecular fraction of nitrogen within the vitamin
was observed. Finally, potential health risks associated with
anticipated CO2-induced deficits of protein, minerals, and
vitamins in rice were correlated to the lowest overall gross domestic
product per capita for the highest rice-consuming countries, suggesting
potential consequences for a global population of approximately 600
million.
Introduction
One of the consequential impacts of rising carbon dioxide
concentration ([CO2]) and climate change is expected to be
on food security.\1\ This expected impact is due, in part, to the
vulnerability of the global population to food supply: Depending on
definition, up to one billion people are deemed food insecure.\2\ For
example, harvests of staple cereal crops, such as rice and maize, could
decline by 20 to 40% as a function of increased surface temperatures in
tropical and subtropical regions by 2100 without considering the
impacts of extreme weather and climate events.\3\ Overall, there has
been a directed effort to understand the consequences of
[CO2] and climate on agricultural production.4, 5
However, the connection between food security and well-being
extends beyond production per se; for example, dietary quality has a
substantial influence on human health.\6\ Globally, insufficient
micronutrients, protein, vitamins, etc. can contribute to nutritional
deficiencies among two billion people in developing and developed
countries.\7\ These deficiencies can directly (cognitive development,
metabolism, and immune system) and indirectly (obesity, type 2 diabetes
mellitus) affect human health on a panoptic scale.\8\
The elemental chemical composition of a plant (that is, ionome)
reflects a balance between carbon, obtained through atmospheric
[CO2], and the remaining nutrients, obtained through the
soil. As evidenced by over a hundred individual studies and several
meta-analyses, projected increases in atmospheric [CO2] can
result in an ionomic imbalance for most plant species whereby carbon
increases disproportionally to soil-based nutrients.9-11
This imbalance, in turn, may have significant consequences for human
nutrition 12, 13 including protein and micronutrients.
However, at present, no information is available regarding a key
constituent of nutrition, vitamin content; as a result, no integrated
assessment (protein, micronutrients, and vitamins) is available.
The consequences of CO2-induced qualitative changes may
be exacerbated where food diversity is limited, that is, where
populations rely heavily on a single plant-based food source. In this
regard, rice supplies approximately 25% of all global calories, with
the percentage of rice consumed varying by socioeconomic status,
particularly in Asia.\14\ Rice is considered among the most important
caloric and nutritional sources particularly for low- and lower-middle-
income Asian countries.\15\
Therefore, for those populations that are highly rice-dependent,
any CO2-induced change in the integrated nutritional value
of rice grains could disproportionally affect health. We use a
multiyear, multilocation, multivarietal evaluation of widely grown,
genetically diverse rice lines at ambient and anticipated end-of-
century [CO2] to (i) quantify varietal response to changes
in dietary components, including protein, iron, calcium, zinc, vitamin
E, and the vitamin B complex, and (ii) socioeconomically calculate any
CO2-induced deficits in these nutritional parameters for the
ten most rice-centric countries globally, as a function of gross
domestic product (GDP) per capita.
Although end-of-century [CO2] projections vary, it is
very likely that actual atmospheric [CO2] will reach 570
mmol mol-1 before the end of this century.\16\ Global
[CO2] is expected to reach these levels even as additional
steps are taken to decrease emissions, due, in part, to the projected
energy usage, the longevity of the CO2 molecule in the
atmosphere, and the temporal delay in reducing [CO2]
emissions before mid-century.\17\ Overall, the experimental
concentrations used here for the elevated [CO2] treatment
(568 to 590 mmol mol-1) reflect the reality that those born
today will be eating rice grown at [CO2] of 550 mmol
mol-1 (or higher) within their lifetimes.
Results
When grown under field conditions at these anticipated
[CO2] a significant reduction (an average of ^10.3%) in
protein relative to current [CO2] was observed for all rice
cultivars (Fig. 1). Similarly, significant reductions in iron (Fe) and
zinc (Zn) were also observed (^8.0 and ^5.1%, respectively) among all
rice cultivars tested (Fig. 2). On the basis of [CO2]
assessment per se, there were no significant site difference effects on
rice grain quality between Japan and China (P = 0.26, 0.17, and 0.10
for protein, iron, and zinc, respectively).
Fig. 1
Average reduction in grain protein at elevated relative to
ambient [CO2] for 18 cultivated rice lines of
contrasting genetic backgrounds grown in China and Japan using
FACE technology.
A country by [CO2] effect on protein reduction was
not significant (P = 0.26). Bars are RSE. *P<0.05 and **P<0.01
(see Methods for additional details).
Fig. 2
Average reduction in grain micronutrients, iron (Fe), and
zinc (Zn) concentration at elevated relative to ambient
[CO2] for 18 cultivated rice lines of contrasting
genetic backgrounds grown in China and Japan using FACE
technology.
A country by [CO2] effect was not significant for
either micronutrient [P = 0.17 and 0.10 for iron (Fe) and zinc
(Zn), respectively] so data from both locations are shown. Bars
are RSE. *P<0.05 and **P<0.01 for a given cultivar.
CO2; **P<0.01 is based on all cultivars (see Methods
for additional details).
The rice lines chosen reflect a wide genotypic and phenological
range, suggesting that the declines in nutrient parameters observed
here are representative of rice in toto. However, a larger sample size
would be of benefit both to confirm these findings and, if possible, to
determine whether any lines may be preferred for improving protein or
micronutrient availability as [CO2] increases.
Regarding the B vitamin complex, significant reductions in vitamins
B1 (thiamine), B2 (riboflavin), B5 (pantothenic acid), and B9 (folate)
were observed in response to projected CO2 levels with
average declines among cultivars of ^17.1, ^16.6, ^12.7, and ^30.3%,
respectively (Fig. 3). As observed for protein and minerals, no
increase in these parameters was detected for any of the 18 rice lines
evaluated; in addition, no significant [CO2] by cultivar
interactions were noted (Fig. 3). In contrast, increases were observed
on average for vitamin E (a-tocopherol) (fig. S1).
Fig. 3
CO2-induced reductions in vitamins B1 (thiamine),
B2 (riboflavin), B5 (pantothenic acid), and B9 (folate) by
cultivar.
No significant effect was observed for vitamin B6
(pyridoxine), and results are not shown. Analysis was conducted
only for the China FACE location. Bars are RSE. *P<0.05 and
**P<0.01 for a given cultivar. CO2; **P<0.01 is
based on all cultivars (see Methods for additional details).
Although these data indicate that [CO2] affects nutrient
composition, the impact of these qualitative changes on health will
vary as a function of rice consumed relative to the total caloric
intake. Previous calculations of the impact of rising CO2 on
human nutrition relied on Food and Agriculture Organization (FAO) food
balance sheets combined with Monte Carlo simulations run on the range
of projected declines of zinc, protein, and iron.12, 13
Here, we also rely on FAO food balance sheets but use an economic
approach whereby average qualitative changes observed with
[CO2] as a function of rice consumption for the top ten
rice-consuming countries as of 2013 are compared with GDP per capita of
that country. In this context, any protein and mineral deficits (Fe +
Zn), associated with higher CO2 values, are observed to be
greater for those countries with the lowest overall GDP per capita (for
example, Bangladesh and Cambodia) (Fig. 4). The reductions in vitamin B
(B1, B2, B5, and B9) availability were greatest for these same
countries (Fig. 4). Similarly, the increase in vitamin E with higher
CO2 levels and the subsequent consumption is proportionally
greater for those poorer countries that ingest greater quantities of
rice (Fig. 4).
Fig. 4
Projected [CO2]-induced deficits in protein and
minerals (Fe and Zn) and cumulative changes in vitamin B and
cumulative changes in vitamin E derived from rice as a function
of GDP per capita.
Data are based on 2011/2013 FAO food balance sheets for rice
consumption and 2011/2013 World Bank estimates of GDP per
capita per country.
There is growing evidence demonstrating a clear link between crop
growth at projected increases in [CO2] and changes in
nutritional quality including, but not limited to, protein, secondary
compounds, and minerals (for example, Zn).9-11, 18, 19 The
basis for the CO2-induced changes in crop quality is still
being elucidated, in part, because increasing [CO2]
influences several biophysical processes.\20\ However, for near-term
projections of [CO2], the qualitative decline can be
reasonably (given the accuracy of the current data) approximated as
linear (for example, protein).\21\
The nutritional data reported here for elevated [CO2]
confirm that deficits in protein, zinc, and iron may occur even among
genetically diverse rice lines grown in different
countries.11, 22 In addition, the current data indicate, for
the first time, a pattern in the changes in vitamin content, that is,
the extent of observed variation between vitamin B (B1, B2, B5, B6, and
B9) and vitamin E (a-tocopherol).
Variation among [CO2]-induced changes in secondary
compounds, such as vitamins, may relate to the well-established decline
of nitrogen in plants exposed to elevated [CO2] [for
example, see the study of Taub, et al.\9\]. The effect of increasing
levels of [CO2] on vitamin levels could therefore be
inversely correlated with the molecular fraction of nitrogen within the
vitamin. This was observed for rice in the current study (r\2\ = 0.82)
(Fig. 5), consistent with the carbon-nutrient balance hypothesis; \23\
at least in the context of rapid increases in atmospheric
[CO2] and carbon availability [but see the study of
Hamilton, et al.\24\], that is, the levels of nitrogen containing
vitamins decreased (B vitamin group), whereas the level of carbon-based
compounds (vitamin E) increased. Additional information regarding the
effects of [CO2] on nutritional quality is obviously
desired; however, this relationship could provide initial guidance as
to the aspects of rice grain chemistry affected by increasing
atmospheric [CO2].
Fig. 5
Average change in vitamin concentration (as percentage) in
response to anticipated, relative to current, [CO2]
RSE as a function of the ratio of the molecular weight of
nitrogen (N) to the molecular weight of the vitamin.
There was a highly significant correlation between the amount
of N present in the vitamin and the overall decrease or
increase in response to higher [CO2].
Discussion
As of 2013, approximately 600 million individuals, primarily in
Southeast Asia [the countries of Bangladesh, Cambodia, Indonesia, Lao
People's Democratic Republic (PDR), Madagascar, Myanmar, and Vietnam],
consume %50% of their per capita dietary energy and/or protein directly
from rice.25, 26 The data shown here provide the first integrated
assessment of [CO2]-induced changes in nutritional quality
(protein, minerals, and vitamins) for many of the most widely grown
rice lines; as such, they indicate that, for key dietary parameters,
the [CO2] likely to occur this century will add to
nutritional deficits for a large segment of the global population.
In assessing the outcome of the [CO2]-induced dietary
changes for rice in the current study, it is evident (Fig. 4) that the
bulk of these changes, and the greatest degree of risk, will occur
among the highest rice-consuming countries with the lowest GDP.
However, as income increases, consumers prefer more diverse caloric
sources, with a greater emphasis on protein from fish, dairy, and meat
as per western foods.\27\ Therefore, future economic development could
potentially limit future CO2-induced changes in rice
nutrition. For example, in Japan, rice accounted for 62% of total food
energy consumption in 1959, but that share fell to 40% by 1976 and, in
recent years, is <20%; \28\ in South Korea, per capita rice consumption
almost halved since 1975.\29\ However, strong, sustained economic
growth cannot be assumed for all rice-consuming countries. For example,
in Bangladesh, 75% of the total caloric supply per capita came from
rice in 1990; 23 years later, in 2013, it was 70% (http://
faostat.fao.org/beta/en/#data/FBS); in Madagascar, the percentage of
rice consumption has increased since 1990.\25\ In addition, other
countries, such as Guinea, Senegal, and Cote d'Ivoire, have become more
reliant on rice as a percentage of their caloric supply (20 to 40% as
of 2011).\30\ Overall, although the top rice-consuming countries are
likely to change in the coming decades, the reliance on rice globally
as a dietary staple will continue.
Specific health outcomes of consuming rice with reduced nutritional
quality are also difficult to forecast. Staple foods, such as rice, are
widely available and affordable for most of the world's population,
particularly the poor. It is understood that undernutrition can put
people at risk in low-income countries for a wide range of other
adverse health outcomes, particularly stunting, diarrheal disease, and
malaria.\31\ For example, Kennedy, et al.,\15\ found that the
percentages of children under 5 years of age who suffer from stunting,
wasting, or are underweight are generally high in countries with very
high per capita rice consumption. Overall, the current data suggest
that, for these countries, any [CO2]-induced change in
nutritional quality would likely exacerbate the overall burden of
disease and could affect early childhood development.
It is difficult, without a great deal of additional socioeconomic
data at the country level (which is often unavailable), to provide
exact estimates of nutritional deficits (protein, minerals, and
vitamins) and associated health consequences likely to incur for rice-
dependent populations. Yet, CO2-induced reductions in these
qualities and associated risks of undernutrition or malnutrition are
likely to transcend the entire food chain, from harvest to consumption,
especially for the poorest people within a country or region.
Is there a way then to reduce--or negate--this risk? Cultivar
selection, either through traditional breeding or genetic modification,
to provide nutritionally superior rice with additional CO2
is an obvious strategy. The current data for a genetically diverse set
of rice lines suggest that, at least for some characteristics (for
example, protein and vitamin B2), many additional lines would need to
be screened; furthermore, at present, it can take many years, even
decades, to identify, cultivate, and distribute new cereal lines that
are adapted to a changing climate.\32\ In addition, other aspects of
climate change, especially temperature, would need to be considered.
For example, previous work indicated that rising temperature per se can
also reduce protein concentration in rice.\33\ Although the extent of
future surface temperatures would vary depending on location,
temperature and [CO2] should also be evaluated concurrently
regarding rice nutritional impacts in future assessments.
In addition, management could include application of mineral
fertilizers or postharvest biofortification. On the consumer side,
education about the role of rising [CO2] on nutrition,
including opportunities to implement favorable nutrition practices and
food fortification, may also provide opportunities to maintain
nutritional integrity. Finally, there is an obvious need for the
research community, including agronomists, physiologists,
nutritionists, and health care providers, to accurately quantify the
exact nature of the [CO2]-induced changes in human
nutritional status and their associated health outcomes.
Whereas much remains to be done, the current study provides the
first evidence that anticipated [CO2] will result in
significant reductions in integrated rice quality, including protein,
minerals, and vitamin B, for a genetically diverse and widely grown set
of rice lines. Occurrence of these nutritional deficits will most
likely affect the poorest countries that are the most rice-dependent.
Overall, these results indicate that the role of rising
[CO2] on reducing rice quality may represent a fundamental,
but underappreciated, human health effect associated with anthropogenic
climate change.
Methods
Free-air CO2 enrichment sites
The multiyear study was conducted at free-air CO2
enrichment (FACE) facilities in two countries: (i) China [at Zhongcun
Village (119420"E, 32355"N), Yangzhou City, Jiangsu Province; as
part of the Yangtze River Delta region, a typical rice growing region
\34\] and (ii) Japan [at Tsukuba (3558N, 13960E), in Ibaraki
Prefecture within farmer's fields \35\]. Eighteen rice lines
representing varietal groups of cultivated rice (Indica and Japonica)
and new hybrid lines were chosen. These lines were, for the most part,
representative and widely grown in the geographical regions where the
FACE facilities were located (Table 1).
Table 1. Characteristics of rice lines used.
------------------------------------------------------------------------
Cultivar Origin Subgroup Comments
------------------------------------------------------------------------
86Y8 China Hybrid Bred for disease-
resistance; high
ripening rate
Bekoaoba Japan Japonica Bred for lodging
resistance, used in
silage
Hokuriku 193 Japan Indica High-yielding, blast-
resistant
Hoshiaoba Japan Japonica Cultivar used for
silage and
bioenergy
IR72 Philippines Indica Semi-dwarf, often
used as check
cultivar
Koshihikari Japan Japonica Widely grown in
Japan
Lemont United States Japonica Semi-dwarf grown in
Mississippi Delta
Milyang 23 Korea Indica High-yielding,
cadmium accumulator
Momiroman Japan Japonica Medium grain, high-
yielding variety
Nipponbare Japan Japonica Genome-sequenced
Liang You 084 China Hybrid Grown extensively in
southeast China
Takanari Japan Indica Widely grown in
Japan
Wuyunjing 21 China Japonica Grown extensively in
East China
Wuyunjing 23 China Japonica Grown extensively in
East China
Yangdao 6 hao China Indica Grown extensively in
East and Central
China
Yliangyou China Hybrid Recently introduced
(2008) hybrid line
Yongyou 2640 China Hybrid Widely planted in
lower Yangtze River
Zhonghua 11 China Japonica Disease-resistant
line used in
breeding
------------------------------------------------------------------------
CO4 and environmental parameters
A complete description of CO2 control for the China and
Japan locations can be found in the studies of Zhu, et al.,\34\ and
Hasegawa, et al.,\35\ respectively. The operation and control systems
for the China FACE facilities were the same as those at the Japan FACE
site. Briefly, each site consisted of identical octagonal rings imposed
on farmer's fields with three rings (China) or four rings (Japan)
receiving pure CO2 supplied from polyethylene tubing
installed horizontally on the periphery of the FACE ring at 30 cm above
the rice canopy (elevated CO2 treatment), with additional
rings (three and four, respectively) that did not receive supplemental
CO2 (ambient CO2 treatment). The concentration of
CO2 was monitored at the center of each ring, and using the
ambient [CO2] as the control, a proportional-integral-
derivative algorithm was used (relative to the ambient control) to
regulate the injection and direction of CO2 in the elevated
ring. Rings were spaced at 90-m intervals to prevent CO2
contamination between plots. Ring diameters varied between locations
(14 and 17 m for the Tsukuba and Zongcun sites, respectively);
[CO2] was controlled to within 80% of the set point for >90%
of the time during the growing season for each location and year. For
the China location, the average daytime [CO2] levels at
canopy height for the elevated treatment were 571, 588, and 590 mmol
mol-1 for 2012, 2013, and 2014, respectively; for the Japan
location, the season-long daytime average CO2 was 584 mmol
mol-1 (2010, Tsukuba); ambient [CO2] varied from
374 to 386 regardless of location.
Rice fields in all locations were flood-irrigated and grown as
``paddy'' rice, as consistent with local practices. For the China
location, the average growing season temperature was 24.4, 24.8, and
22.1 C for 2012, 2013, and 2014, respectively; for Japan, the growing
season temperature was 24.6 C for the Tsukuba location in 2010. The
soil type in the China location was classified as Shajiang-Aquic
Cambiosol with a sandy loam texture. The soil type at Tsukuba, Japan is
Fluvisols, typical of alluvial areas. Fertilizer was applied at rates
to maximize commercial yield, consistent with location; any additional
pesticides were consistent with cultural agronomic practices for the
given region. Sowing and transplanting methods are described
elsewhere.34, 35 At seed maturity, 1 to 2 m\2\ per
CO2 ring, per cultivar, per year, and per location were
harvested for yield assessment.
Nutrient analysis
For the China FACE, a subsample (500 g) of grain was frozen before
analysis. Dehusked (unpolished) brown (raw and uncooked) rice (100 g)
was homogenized to a fine powder using a Mix/Mill Grinder, sifted
through a 100-mesh sieve, and then dried to a constant weight at 70 C.
A 0.5-g sample was added to a graphite tube for digestion, 0.2 ml of
pure deionized (DI) water was added, followed by 8 ml of
HNO3, and digested for 24 hours. An additional 2 ml of
HCLO4 was then added. Digestion temperature was regulated
until clear color was obtained. Finally, DI water was added to increase
any remaining solution to 50 ml. Inductively coupled plasma (ICP)
atomic emission spectrometry (AES) (Optima 8000, PerkinElmer) was used
to determine Ca content, whereas ICP-mass spectrometry (MS) (7700,
Agilent) was used to determine Fe and Zn content. Elemental analyses
for the samples from the Tsukuba FACE location are described by
Dietterich, et al.\36\ Briefly, the air-dried husked (but unpolished)
brown rice grains were air-dried and ground as described previously.
Nitrogen was analyzed with a Leco TruSpec CN analyzer. Fe, Zn, and Ca
were determined with an ICP optical emission spectrophotometer. Note
that brown rice was analyzed because previous publications [for
example, the study of Myers, et al. \11\] had used brown rice as the
standard for CO2 effects on nutrition.
Elemental concentrations of carbon and nitrogen were determined for
an additional 30 mg of harvest sample using an elemental analyzer
(Vario, MAX CN, Element). Nitrogen content and carbon content were
determined as a percentage of the dry weight of the sample. A factor of
5.61 was used for converting nitrogen to protein concentration in rice,
consistent with previous studies.\37\
Vitamin extraction and analysis
Although rice does not supply the complete vitamin B complex, it is
known to provide B1, B2, B5, B6, and B9, as well as vitamin E. These
were extracted from dehusked, unpolished brown rice seed for the nine
rice cultivars at the China FACE location. Brown rice (100 g) was
homogenized to a fine powder using the previously described method;
then, frozen sample was lyophilized using a VFD-1000 freeze dryer
(Bilon). Lyophilization occurred in two cycles; drying at ^20 C for 48
hours, followed by secondary drying at 0 C for 3 hours.
For thiamine, riboflavin, pantothenic acid, and pyridoxine
determination, 0.05 g of ascorbic acid was added to homogenized samples
(0.5 g) as an antioxidant and then followed by 10 ml of extracting
solution (methanol/water/phosphoric acid = 100:400:0.5, v/v/v). After
the suspension was vortexed, it was autoclaved at 100 C for 20 min and
then incubated under ultrasonic conditions for 30 min. The solution was
allowed to cool to room temperature and then centrifuged at 11,945g for
15 min. Blank controls were generated following the same process
without rice samples. The final supernatant was filtered through a
0.22-mm filter before high-performance liquid chromatography (HPLC)-MS
analysis.
Folate determination was per Blancquaert, et al.: \38\ 4 ml of
extraction buffer was added to 0.5 g of homogenized samples, and the
capped tube was placed at 100 C for 10 min. A tri-enzyme treatment
with 80 ml of a-amylase (20 min), 350 ml of protease (1 hour at 37 C),
and 250 ml of conjugase (2 hours at 37 C) was used to degrade the
starch matrix, to release protein-bound folates, and to deconjugate
polyglutamylated folates. To stop protease and conjugase activity,
additional heat treatments were carried out, followed by cooling on
ice. The resulting solution was ultrafiltrated at 11,958g for 15 min.
The final solution was filtered through a 0.22-mm filter before
analysis.
Vitamin E (a-tocopherol) was extracted using an improved method, as
described by Zhang, et al.\39\ One gram of the homogenized fine powder
was saponified under nitrogen in a screw-capped tube with 1 ml of
potassium hydroxide (600 g/liter), 5 ml of ethanol, 1 ml of sodium
chloride (10 g/liter), and 2.5 ml of ethanolic pyrogallol (60 g/liter)
added as antioxidants. Tubes were placed in a 70 C water bath and
mixed at 5-min intervals during saponification. Following alkaline
digestion at 70 C for 30 min, the tubes were cooled in an ice bath,
and 5 ml of sodium chloride (10 g/liter) was added. The suspension was
extracted twice with 8 ml of n-hexane/ethyl acetate (4:1, v/v). The
organic layer was collected and was dried using pure nitrogen (EVA 30A,
Polytech Co.) and then dissolved in n-hexane/methanol (20:80, v/v; 1.
ml). A similar procedure was used to generate a blank control. The
final solution was filtered through a 0.22-mm filter before analysis.
HPLC-tandem MS (Thermo Finnigan TSQ) was used to quantify vitamin
content. Column oven temperature was maintained at 25 C, and the
autosampler was maintained at 4 C. Two separate Phenomenex Kinetex C18
columns (4.6 mm 100 mm 2.6 mm and 4.6 mm 30 mm 5 mm) were used
for vitamins B and E, respectively. Injection volume was 20 ml. For
gradient elution, the mobile phase consisted of eluent A (methyl
alcohol) and eluent B (0.1% formic acid in water), with each eluent
pumped at a flow rate of 0.6 ml min-1. The mobile phase was
linearly adjusted to separate the different vitamins (table S1).
For the MS setting, source conditions were optimized for vitamin B
as follows: ion source, electrospray ionization; spay voltage, 3500 V;
vaporizer temperature, 400 C; capillary temperature, 350 C; sheath
gas pressure, 50; auxillary gas pressure, 10; scan type, selected
reaction monitoring (SRM); collision pressure, 1.0-mtorr Ar. For
vitamin E, the source conditions were optimized as follows: ion source,
atmospheric pressure chemical ionization; discharge current, 10 mA;
vaporizer temperature, 300 C; capillary temperature, 350 C; sheath
and auxiliary gas pressure, 50 and 10, respectively; scan type, SRM;
collision pressure, 1.0-mtorr Ar (table S2). Known standards for
vitamin B1 (thiamine hydrochloride), vitamin B2 (riboflavin), vitamin
B5 (calcium-D-pantothenate), vitamin B6 (pyridoxine hydrochloride),
vitamin B9 (folic acid), and vitamin E (a-tocopherol) were purchased
from Sigma-Aldrich Co. All vitamin analyses were performed in
duplicate. Before sample analysis, the instrument was calibrated using
seven standards (six standards and the blank control).
Estimate of nutritional deficits
The ten most rice-dependent countries were determined on the basis
of the largest consumption of rice as a fraction of total available
calories [Bangladesh, Cambodia, China, Indonesia, Lao PDR, Madagascar,
Myanmar, Philippines, Thailand, and Vietnam (23)]. FAO food balance
sheets (http://faostat.fao.org/beta/en/#data/FBS; food supply quantity,
kilogram per capita per year and food supply, and kilocalorie per
capita per day) from either 2011 (Cambodia and Lao PDR) or 2013 (all
other countries) were used to determine rice consumption along with the
U.S. Department of Agriculture (USDA) National Nutrient Database for
Standard Reference data for raw brown long-grain rice (https://
ndb.nal.usda.gov/ndb/foods/show/305240?manu=&fgcd=&ds=SR) to quantify
any CO2-induced differences in qualitative nutritional
characteristics by individual country.
With respect to nutritional characteristics, we used a holistic
approach to assess changes in a number of qualitative parameters
including protein, minerals (Fe, Ca, and Zn), and vitamins B1
(thiamine), B2 (riboflavin), B5 (pantothenic acid), B6 (pyridoxine), B9
(folic acid), and E (a-tocopherol). Inadequate intake of the vitamins
and minerals assessed were associated with specific physiological
conditions and clinical manifestations.\40\ Data for protein and
minerals were available for all three experimental locations; however,
vitamin analysis was only conducted for the rice lines from the China
location. Because income level is the most important determinant of per
capita rice consumption,\25\ and because of the wide range of per
capita incomes of the countries assessed, any significant
CO2-induced change in a nutritional characteristic was
characterized with respect to GDP per capita (from 2013) for the ten
countries examined (https://data.worldbank.org/indicator/NY.GDP.
PCAP.CD).
Statistics
All field experiments at each location represented a completely
randomized design with either three (China) or four (Japan) replicates.
All measured and calculated parameters were analyzed using a two-way
analysis of variance (ANOVA) with [CO2] and cultivar as
fixed effects (Statview Software). Coefficient of determination (r\2\)
was calculated for protein, mineral (Fe and Zn), and vitamin (B1, B2,
B5, B6, B9, and E) deficits as a function of [CO2] and GDP
per capita. Each value is the mean RSE. **P<0.01; *0.01 5P<0.05; *0.05
5P<0.1; ns, not significant (P50.1). The figures were generated using
Systat Software (SigmaPlot 10.0, Systat Software Inc.). No significant
differences for [CO2] by cultivar interaction were found for
calcium (Ca) or vitamin B6; consequently, these data are not shown
separately. Every cultivar was grown only at a single site, which does
not allow separation of cultivar effects from site effects. However,
when averaged for all cultivars within a single location (Japan or
China), no significant country interaction was observed for
[CO2] impacts on noted reductions in protein, iron, or zinc
(P = 0.26, 0.17, and 0.1 for protein, iron, and zinc, respectively).
Because our purpose was to elucidate the effect of [CO2] on
rice, but not on geographic area, cultivar effects are inclusive for
the figures. Seasonal (yearly) variation was not significant for a
given location and, consequently, was averaged across years for each
FACE site. Original data are available at https://doi.org/10.6084/
m9.figshare.6179069.
Supplementary Materials
Supplementary material for this article is available at http://
advances.sciencemag.org/cgi/content/full/4/5/eaaq1012/DC1.
Table S1. Elution procedures for vitamin B and vitamin E.
Table S2. Compound parameters for vitamins B1, B2, B5, B6, B9 and
E.
Fig. S1. As for Fig. 3, but for vitamin E (a-tocopherol) (see
Methods for additional details).
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Acknowledgments: We thank G. Kordzakhia of the U.S. Food and Drug
Administration for his contributions. Funding: This work was supported
by the National Basic Research Program of China (973 Program,
2014CB954500), Natural Science Foundation of Jiangsu Province in China
(BK20140063), Youth Innovation Promotion Association of Chinese Academy
of Sciences (CAS; member no. 2015248), and the frontier projects for
13th 5 year plan of CAS (Y613890000 to C.Z.). Author contributions:
C.Z., L.H.Z., and K.K. designed the study. I.L., S.S., and K.L.E. did
the literature review. I.L., C.Z., and L.H.Z. did the analysis with
contributions from K.L.E., N.K.F., and A.D. J.Z., Q.J., X.X., and G.L.
contributed data. L.H.Z. wrote the report. All authors interpreted the
results, commented on the draft version of the report, and approved the
submission draft. Competing interests: A.D. has received grants,
honoraria, and consulting fees from numerous food, beverage, and
ingredient companies and other commercial and nonprofit entities with
an interest in diet quality and nutrient content of foods. The
University of Washington receives research funding from public and
private sectors. N.K.F. is the Editor-in-Chief of Nutrition Reviews, an
International Life Sciences Institute publication, and has received
honoraria from Monsanto and the National Dairy Council before
employment by the USDA. The other authors declare that they have no
other competing interests. Data and materials availability: All data
needed to evaluate the conclusions in the paper are present in the
paper and/or the Supplementary Materials. Original data are available
at https://doi.org/10.6084/m9.figshare.6179069.
Submitted 1 October 2017
Accepted 6 April 2018
Published 23 May 2018
10.1126/sciadv.aaq1012
______
Submitted Reports by Hon. David Scott, a Representative in Congress
from Georgia *
---------------------------------------------------------------------------
* Editor's note: the reports listed are retained in Committee file.
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______
Submitted Letters by Hon. David Scott, a Representative in Congress
from Georgia
Letter 1
on behalf of chad hanson, ph.d., chief scientist and director; jennifer
mamola, d.c. forest protection advocate, john muir project
March 12, 2021
Hon. David Scott, Hon. Glenn Thompson,
Chairman, Ranking Minority Member,
House Committee on Agriculture, House Committee on Agriculture,
Washington, D.C.; Washington, D.C.
Re: House Agriculture Hearing on Climate Change and the U.S.
Agriculture & Forestry Sectors
Dear Mr. Chairman, Ranking Member, Members and Staff;
Last month we virtually attended your February 25th Agriculture
Hearing on Climate Change and the U.S. Agriculture and Forestry
Sectors. The majority of the focus was on how best to address issues
within the agriculture sector which should be applauded as now more
than ever we need to truly focus on those communities that feed us.
Unfortunately, the brief mention of forests was often undermined by a
demonization of nature, with a focus on logging under the guise of
``fuel reduction'',which releases more carbon into the atmosphere and
often makes fires burn more intensely.
Unfortunately, at times the focus of the hearing veered away from
solutions that would benefit society, the environment, and help us to
solve the climate crisis. We are writing this letter to hopefully bring
some balance to the testimony, verbal and written, that was presented
and to address the problematic underlying narrative which appears to be
shifting Members' attention away from actions that will actually make a
difference for people and the planet.
1. Vegetation is not driving wildfires: our forests aren't
overstocked
Since the King Fire (see map below) was referenced and
vegetation was blamed, it's probably one of the best
examples of when the winds are blowing hard and the fire
starts a major run, thinning or any other treatment
(including prescribed fire) just doesn't prevent or stop
fire. That fire burned almost exclusively at high severity
in one particular portion of the fire on a huge run during
a single day that was all due to a crazy localized wind
event. That single day accounted for almost all of the high
severity burned area in that fire, due to high wind.
Figure 1
(a) 2018, Coen, et al., Deconstructing the King megafire;
(b) https://climate.nasa.gov/news/2771/local-winds-play-a-key-
role-in-some-megafires/.
Editor's note: entries annotated with are retained in
Committee file.
Meaning, the number one driver of fire behavior and extent is
the climate, specifically high temperatures, extreme wind
speeds and single digit humidity. Climate change is making
these conditions more prevalent, more often. It is also
important to appreciate the fact that we do not currently
have an excess of fire in forests. We have always had fires
in the West and always will, and there is wide agreement
among scientists that we currently have less mixed-
intensity fire in our forests than we did historically,
before fire suppression and, while annual acres burned is
incrementally getting slightly closer to historical levels,
in part due to climate change, fire intensity in forests is
not increasing.\1\ The real issue is that, increasingly,
climate and weather factors drive fires that humans are not
able to suppress. Fires that cannot be suppressed,
especially when they are started by human ignitions or
infrastructure, have the potential to burn into and affect
communities which have sprawled over time into our fire-
adapted ecosystems.
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\1\ (a) DellaSala, D.A., and C.T. Hanson (Editors). 2015. The
ecological importance of mixed-severity fires: nature's phoenix.
Elsevier Inc., Waltham, MA, USA; (b) Keyser, A.; Westerling, A. Climate
drives inter-annual variability in probability of high severity fire
occurrence in the western United States. Environ. Res. Lett. 2017, 12,
65003.
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There are several ways that we know it is climate conditions,
rather than the vegetation, that is driving fire behavior.
First, and most informative are the field-based studies
that have looked at the effect, if any, that decades of
successful fire suppression has had on fire intensity.
Specifically, seven studies have investigated whether areas
that have not experienced fire in a very long time (i.e.,
areas that have had the chance for vegetation to grow
unimpeded for a century or more) burn at higher intensity
than areas which have experienced fire more recently. Three
of the seven studies found unequivocally that areas that
have not burned in a very long time do not burn at higher
intensities than areas that have burned in recent decades,
three of the remaining four studies found that the most
long-unburned forests (the densest forests) burned at lower
intensities than other forests, and the final of the seven
studies speculated that long-unburned forests would burn
slightly more intensely but would still be dominated by
lower-intensity fire effects (and this study, unlike the
other six, involved a theoretical model, and its conclusion
was not based on actual fire data).\2\
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\2\ (a) Miller J.D., Skinner C.N., Safford H.D., Knapp E.E.,
Ramirez C.M. 2012a. Trends and causes of severity, size, and number of
fires in northwestern California, USA. Ecological Applications 22,
184-203; (b) Odion, D.C., E.J. Frost, J.R. Strittholt, H. Jiang, D.A.
DellaSala, and M.A. Moritz. 2004. Patterns of fire severity and forest
conditions in the Klamath Mountains, northwestern California.
Conservation Biology 18: 927-936; (c) Odion, D.C., and C.T. Hanson.
2006. Fire severity in conifer forests of the Sierra Nevada,
California. Ecosystems 9: 1177-1189; (d) Odion, D.C., and C.T. Hanson.
2008. Fire severity in the Sierra Nevada revisited: conclusions robust
to further analysis. Ecosystems 11: 12-15; (e) Odion, D.C., M.A.
Moritz, and D.A. DellaSala. 2010. Alternative community states
maintained by fire in the Klamath Mountains, USA. Journal of Ecology,
doi: 10.1111/j.1365-2745.2009.01597.x; (f) van Wagtendonk, J.W., K.A.
van Wagtendonk, and A.E. Thode. 2012. Factors associated with the
severity of intersecting fires in Yosemite National Park, California,
USA. Fire Ecology 8: 11-32; (g) Steel, et al. 2015. Ecosphere 8:
Article 8.
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Next we have empirical research which has investigated whether
the number of dead trees in a given area drives fire
behavior. The most comprehensive scientific studies
(including one prepared by NASA) found that forests with
more dead trees burn the same as other forests or burn at
lower intensities.\3\ While it may seem counterintuitive,
soon after trees die (whether from drought or beetle
activity), they shed their needles and small branches which
fall to the ground and decay into soil and there is no real
mechanism to carry flames.
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\3\ (a) Hart, S.J., T. Schoennagel, T.T. Veblen, and T.B. Chapman.
2015. Area burned in the western United States is unaffected by recent
mountain pine beetle outbreaks. Proceedings of the National Academy of
Sciences of the USA 112: 4375-4380; (b) Meigs, G.W., H.S.J. Zald, J.L.
Campbell, W.S. Keeton, and R.E. Kennedy. 2016. Do insect outbreaks
reduce the severity of subsequent forest fires? Environmental
Research Letters 11: 045008.
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Importantly, our forests currently have significantly less tree
biomass in them than they did historically, due to decades
of logging. Claims that our forests are ``overstocked'' are
quite simply misleading.\4\
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\4\ (a) McIntyre, P.J., et al. 2015. Twentieth-century shifts in
forest structure in California: Denser forests, smaller trees, and
increased dominance of oaks. Proceedings of the National Academy of
Sciences of the United States of America 112: 1458-1463; (b) Erb, K.H.,
et al. 2018. Unexpectedly large impact of forest management and grazing
on global vegetation biomass. Nature 553: 73-76.
2. Since vegetation is not driving wildfires, vegetation management,
thinning and other forms of logging, and prescribed burning
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are not necessary
Climate and weather are driving wildfire behavior, but to the
extent that density of vegetation has an influence, it is
the opposite of what many assume. Numerous studies have
investigated this issue, measuring forest density directly
and how it relates to fire behavior. These studies, similar
to the ones referenced above, also found that the densest
mature forests generally burn at lower intensities. This is
because denser forests have more trees, which provide more
shade, which keep conditions cooler and more moist. Whereas
forests with fewer trees, often due to logging/mechanical-
thinning, burned at higher intensities. This is because
logging reduces the cooling shade of the forest canopy,
creating hotter, drier conditions, while also removing
trees which have a buffering effect on wind speeds,
eliminating the forests ability to slow fire spread. Far
from being a ``fire'' solution, logging/thinning does not
stop fires, and fires often move more rapidly through these
areas. Further, the most comprehensive scientific study
ever conducted on this question found that forests with the
most logging a.k.a ``forest management'' burn the most
intensely, not the least.\5\
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\5\ (a) Bradley, C.M. C.T. Hanson, and D.A. DellaSala. 2016. Does
increased forest protection correspond to higher fire severity in
frequent-fire forests of the western USA? Ecosphere 7: article
e01492; (b) Zald, H.S.J., and C.J. Dunn. 2018. Severe fire weather and
intensive forest management increase fire severity in a multi-ownership
landscape. Ecological Applications 28: 1068-1080; (c) Meigs, G., D.
Donato, J. Campbell, J. Martin, and B. Law. 2009. Forest fire impacts
on carbon uptake, storage, and emission: The role of burn severity in
the Eastern Cascades, Oregon. Ecosystems 12: 1246-1267; (d) Cruz,
M.G., M.E. Alexander, and J.E. Dam. 2014. Using modeled surface and
crown fire behavior characteristics to evaluate fuel treatment
effectiveness: a caution. Forest Science 60: 1000-1004; (e) DellaSala,
D.A,, C.T. Hanson. 2019. Are wildland fires increasing large patches of
complex early seral forest habitat? Diversity 11: Article 157.
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Prescribed fire does not stop wildland fires either. In fact,
wildland fires can burn again even within as little as 1 or
2 year after a prescribed fire, as we just saw in Australia
(the bushfires burned right through the largest prescribed
burn in the nation's history, which was conducted in 2017).
Historically, forests burned every few decades, not every 2
years.\6\ If we attempt to ``fireproof'' the landscape with
prescribed fire, we would be imposing far more fire than is
natural on ecosystems, impacting biodiversity and damaging
soils and forest productivity all while creating vastly
more smoke than currently occurs with wildland fires--and
it would not stop wildland fires.
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\6\ DellaSala, D.A., and C.T. Hanson (Editors). 2015. The
ecological importance of mixed-severity fires: nature's phoenix.
Elsevier Inc., Waltham, MA, USA.
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Pursuing a ``forest management'' approach to fire fundamentally
ignores and denies that climate is driving fire behavior.
These activities will not solve our community protection
problem, or assist with climate adaptation and will
exacerbate rather than mitigate the climate and extinction
crises we currently face. Not to mention the colossal
amounts of money that is burned in the backcountry. A
witness even stated they'd love to see more money spent,
yet all that would do is emit even more carbon into the
atmosphere while communities continue to be ill-prepared
for the inevitable fire season.
3. To protect communities, we must focus on communities
Fires are ultimately weather driven events, similar to
tornadoes and hurricanes. Accepting this will enable us to
do what is necessary to focus our efforts on community
protection, resilience, disaster preparedness and
mitigation. Outside of putting resources into stopping
human ignitions via more patrols during high fire weather
and educating the public about fire-safe activities, once a
fire starts under extreme weather conditions it is going to
burn.
According to the scientific research the only effective way to
protect homes from wildland fire is to focus on making the
homes themselves more fire-safe, and to conduct annual
defensible space pruning within 100 of homes. Beyond 100
from houses, there is no additional benefit to home
protection from vegetation management.\7\ Congressional
resources should be put into such efforts, similar to a
bill from the 116th Congress that took a first step in this
direction S. 2882/ H.R. 5091 Wildfire Defense Act.
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\7\ Syphard, A.D., T.J. Brennan, and J.E. Keeley. 2014. The role of
defensible space for residential structure protection during
wildfires. Intl. J. Wildland Fire 23: 1165-1175.
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Because we cannot suppress weather driven fires, we cannot stop
the smoke that they create. What we can and must do is
promote measures that will keep people safer and help
communities adapt: by devoting resources to help create
better fire and smoke warning and evacuation systems;
develop programs which help homeowners in need with air
filters for smoke, and access to appropriate respiratory
masks (as mentioned at the hearing); create smoke relief
centers for sensitive groups; have options for emergency
housing; daycare; rideshares to work and always ensure that
these services are available to everyone, regardless of
income.
Unfortunately, employing forest management, by way of logging
and removal of vegetation from our forests, as a ``fire
fix'' diverts scarce resources away from measures that
would actually make people safer, and it gives communities
a dangerous and false sense of security because such
actions will not stop fires or alter weather driven fire
behavior. We saw a tragic example of this in the Camp fire
of 2018, which burned so rapidly through several thousand
acres of heavily managed forestland (which had been post-
fire clearcut and/or thinned) during the first 6 hours of
the fire that people within the towns of Paradise and
Concow had very little time to evacuate, with tragic
results. So called fuels reduction and post-fire
``restoration'' did not save these towns from this weather
driven fire, it made the tragedy worse.\8\
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\8\ https://johnmuirproject.org/2019/01/logging-didnt-stop-the-
camp-fire/.
4. Forests, as they exist right now, are a climate solution not a
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climate problem
Our forests are currently substantial carbon sinks, absorbing
more carbon than they emit, but they could absorb much more
carbon than they currently do, if they were protected from
logging. Logging is the real source of carbon emissions
from forests. In U.S. forests, for example, logging (of all
types, thinning/post-fire/clearcutting/group-selection,
etc.) emits ten times more carbon than is emitted from
wildland fire and tree mortality from drought and native
bark beetles combined. Dead trees and downed logs decay
extremely slowly (decades to a century or more), and
eventually return their nutrients to the soil, which helps
maintain the productivity and carbon sequestration capacity
of the forest.\9\
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\9\ (a) Harris, N.L., et al. 2016. Attribution of net carbon change
by disturbance type across forest lands of the conterminous United
States. Carbon Balance Management 11: Article 24; (b) Meigs, G., et
al. 2009. Forest fire impacts on carbon uptake, storage, and emission:
The role of burn severity in the Eastern Cascades, Oregon. Ecosystems
12: 1246-1267; (c) Meigs, G.W., H.S.J. Zald, J.L. Campbell, W.S.
Keeton, and R.E. Kennedy. 2016. Do insect outbreaks reduce the severity
of subsequent forest fires? Environmental Research Letters 11:
045008.
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Wildland fires, including large mixed-severity fires, only
consume about 1% to 2% of the biomass of trees in the
forest, and therefore only release this small portion of
the carbon stored in trees into the atmosphere. We know
this from field-based studies of actual fires in actual
forests. The problem is that Federal and state agencies use
theoretical models to estimate carbon emissions from forest
fires and dead trees, but the models wildly exaggerate
carbon emissions from decay and fire. For example, in the
257,000 acre Rim fire of 2013, field-based data determined
that only \1/10\ of 1% of the carbon in trees was actually
consumed in typical fire conditions, whereas the
theoretical models falsely assume levels of consumption
that are often dozens, or hundreds, of times higher than
this.\10\
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\10\ Stenzel, J.E., et al. 2019. Fixing a snag in carbon emissions
estimates from wildfires. Global Change Biology 25: 3985-3994.
5. The proposals supported by the witnesses will harm our
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environment, biodiversity and the climate
There was discussion and written testimony at this hearing of
logging as an answer to the ``fire'' problem. But we
actually don't have a fire problem in our forest
ecosystems. We have substantially less mixed-intensity fire
now than we had historically, before fire suppression. In
addition, wildland fires, especially the large fires that
burn at mixed-intensity, transform forest ecosystems but do
not destroy them. In fact these fires create natural
heterogeneity across vast areas, rejuvenating wildlife
habitat to such a degree that the biodiversity in mature
forests that experience high-intensity fire is similar to
levels of biodiversity found in unlogged old-growth
forests, and the same is true for areas which have
experienced drought and beetle related tree mortality.\11\
In addition, forests are naturally regenerating even in the
largest high-intensity fire patches.
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\11\ DellaSala, D.A., and C.T. Hanson (Editors). 2015. The
ecological importance of mixed-severity fires: nature's phoenix.
Elsevier Inc., Waltham, MA, USA.
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While we do not have a fire in our forests problem, we most
certainly do have a problem with fire affecting our
communities and a climate change problem. We therefore need
solutions to protect and adapt communities and to combat
climate change. Logging, whether you call it thinning,
vegetation management, forest management or biomass
removal, will remedy neither of these problems and actually
makes things worse. It is simply another part of the carbon
economy. Since no witness at the hearing addressed the
carbon cost of logging we thought we would share some
statistics here. Due to its industrial nature,
approximately 81% of the carbon in trees that are logged
quickly ends up in the atmosphere, with only 19% ending up
being stored in wood products. Logging also removes
nutrients from forests and compacts soils, reducing the
overall productivity and function of the forest ecosystem
as well as its carbon sequestration and storage
capacity.\13\ Notably, numerous studies find that logging
conducted under the guise of ``thinning'', ``fuels
reduction'' and fire management actually causes a large net
loss of forest carbon storage and a substantial net
increase in carbon emissions relative to wildland fire
alone.\14\
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Editor's note: the letter submitted by the John Muir project does
not have a footnote reference for footnote no. 12. It has been
reproduced, as submitted, herein. Below is footnote 12 that was
included at the end of the letter.
\12\ Hudiburg, T.W., Beverly E. Law, William R. Moomaw, Mark E.
Harmon, and Jeffrey E. Stenzel. 2019. Meeting GHG reduction targets
requires accounting for all forest sector emissions. Environmental
Research Letters 14: Article 095005.
\13\ (a) Walmsley, J.D., et al. 2009. Whole tree harvesting can
reduce second rotation forest productivity. Forest Ecology and
Management 257: 1104-1111; (b) Elliot, W.J., et al. 1996. The effects
of forest management on erosion and soil productivity. Symposium on
Soil Quality and Erosion Interaction. July 7, 1996, Keystone, CO.
\14\ (a) Campbell, J.L., M.E. Harmon, and S.R. Mitchell. 2012. Can
fuel-reduction treatments really increase forest carbon storage in the
western U.S. by reducing future fire emissions? Frontiers in Ecology
and Environment 10: 83-90; (b) Hudiburg, T.W., et al. 2013. Interactive
effects of environmental change and management strategies on regional
forest carbon emissions. Environmental Science and Technology 47:
13132-13140.
We hope that you have found the above information helpful and we
urge you to consider the foregoing, and to reject false climate
solutions that would make climate change worse and increase risks to
vulnerable communities. We need to increase protection of our forests
from logging, and focus resources on directly protecting and helping
vulnerable communities. The recommendations made by numerous speakers
at the hearing, and the comments made by some Members, would take us in
the wrong direction. We would be happy to answer questions or provide
additional information, so please feel free to contact us if you would
like to have a dialogue on these issues.
Sincerely,
Chad Hanson, Ph.D., Jennifer Mamola,
Chief Scientist and Director, D.C. Forest Protection Advocate,
John Muir Project; John Muir Project.
Letter 2
on behalf of john linder, president, national corn growers association
March 5, 2021
Hon. David Scott,
Chairman,
House Committee on Agriculture,
Washington, D.C.;
Hon. Glenn Thompson,
Ranking Minority Member,
House Committee on Agriculture,
Washington, D.C.
Dear Chairman Scott and Ranking Member Thompson:
On behalf of the National Corn Growers Association (NCGA), we
appreciate the opportunity to submit this statement outlining corn
grower priorities on policies related to climate change. We request
this statement be included in the record for the February 25, 2021
hearing of the House Agriculture Committee, ``Climate Change and the
U.S. Agriculture and Forestry Sectors.''
Founded in 1957, NCGA represents nearly 40,000 dues-paying corn
farmers nationwide and the interests of more than 300,000 growers who
contribute through corn checkoff programs in their states. NCGA and its
48 affiliated state organizations work together to create and increase
opportunities for corn growers. Corn provides a nutritious and
sustainable feed for the global livestock sector, supplies the world
with renewable fuel and replaces petroleum and other non-renewable
ingredients in a variety of industrial and consumer products.
NCGA supports the agriculture sector's opportunity to contribute to
carbon reduction based on carbon offsets and carbon sequestration
through crop production, as well as through further decarbonization of
transportation fuels through increased use of renewable fuels. Further,
NCGA supports market-based, voluntary opportunities for farmers to
provide carbon reduction benefits.
A changing climate poses a unique threat to agriculture because
weather has a direct impact on farm production and profitability. With
weather likely to become even more unpredictable, a reliable and
consistent food supply for a growing population is more important than
ever before. Building upon the strong foundation of voluntary
stewardship investments andsustainable farming practices, climate
policy should support research and innovation needed todevelop new
technologies that will help farmers respond to climate change and
continuereducing greenhouse gas emissions.
Soil Carbon Sequestration Potential
Corn as a crop can serve as a carbon sink. As a photo-synthetically
superior C4 plant, corn has an extraordinary ability to
sequester carbon and move fertilizer nutrients back to the surface for
plant growth rather than into ground water. Corn's extensive, deep root
system makes it one of the few plants with this important capability to
make crop production more sustainable.
High-yield corn--combined with the steady adoption of best
practices such as reductions in tillage intensity--is sequestering
carbon from the atmosphere into the soil. This sequestration is
increasing soil carbon levels and reducing atmospheric carbon.
According to the Journal of Soil and Water Conservation, the potential
to sequester atmospheric carbon in soil is greatest on lands currently
used for annual crops where there is potential to sequester carbon in
the soil at an annual growth rate of 0.4 percent each year. The results
of tracking soil organic carbon advancements on select USDA-specified
agricultural land areas is estimated to have sequestered an estimated
309 metric tons of CO2-equivalent in less than a decade.
Research increasingly demonstrates the ability to account for the
direct effects corn production has on soil carbon stocks, whether as
part of climate change policy, carbon markets that support agriculture
or in ethanol lifecycle assessment (LCA) accounting such as the
Department of Energy's Argonne National Lab Greenhouse gases, Regulated
Emissions, and Energy use in Transportation (GREET) model.
NCGA's Soil Health Partnership and Climate
Soil health practices and management systems hold the potential to
mitigate climate change but further research is needed to fully
understand the benefits of soil health practices. There is a major gap
in understanding how soil health practices impact soil health, water
quality, air quality and greenhouse gas (GHG) emissions.
NCGA is working to bridge this gap through its flagship
sustainability program, the Soil Health Partnership (SHP). SHP's
mission is to utilize science and data to partner with farmers who are
adopting agricultural conservation practices that improve economic and
environmental sustainability. The partnership has more than 220 working
farms enrolled in 15 states. It is the only farmer-led effort that
focuses on supporting farmers as they experiment with new conservation
practices like cover crops, reduced or no tillage and nutrient
management with the benefit of support from SHP expert partners. SHP
works with farmers to achieve the goal of broader adoption of
conservation practices and understanding how varying practices affect
the environment.
SHP is focused on soil health improvements as the key
transformation that facilitates many subsequent improvements ranging
from increased productivity, increased resilience to weather changes,
improved water quality, reduced soil erosion and increased carbon
sequestration. The soil health indicators measured are both
quantitative and qualitative to gauge the intermediate and long-term
impacts of these changes.
Farmers enroll to run research trials on their active farms, with
data collected on 165 variables over 5 years. As a result, SHP has one
of the most unique data sets in the country that combines information
from diverse farms across 15 states, multiple years, and many soil
types to allow for an analysis of trends. SHP will soon be able to
analyze the impact of various conservation practices on the
environment, coupled with an understanding of the management decisions
made to put those practices in place and how they impact farmers
economically.
Farmers are making major impacts on the environment in ways that
have been historically underestimated. SHP's initial analyses show
increases in soil organic matter of about \1/4\ of 1 percent over the
first 2-3 years in the program, which suggests improved soil water
holding capacity and possibly carbon storage over time. Currently,
there is not sufficient longitudinal, diverse data to fully understand
the long-term impacts of various conservation practices on climate
outcomes, e.g., GHG emissions, but through SHP's continued work, we
will be able to understand the impact and better target our resources
and energy to benefit farmers and the environment.
In addition to measuring changes in soil organic matter over time,
SHP is also part of a multiyear, multi-partner Conservation Innovation
Grant through USDA NRCS to create a carbon accounting and insetting
framework that would enable companies along the supply chain to
encourage farmers to adopt conservation practices such as reduced
tillage and cover crops to sequester carbon in the soil. The framework
employs the DeNitrification-DeComposition (DNDC) model to model GHG
impacts from on-farm practice changes and uses the Operational Tillage
Informational System (OpTIS) as a low-cost, low-touch verification tool
for the framework.
Biotechnology, Crop Protection Tools and Climate Change
Prior to the introduction of transgenic seeds tolerant to broad-
spectrum pesticides, farmers were forced to rely on tillage to manage
weeds in their fields. When the first transgenic, or GMO, crops became
commercially available, farmers were no longer forced to rely solely on
tillage for weed control.
Transgenic seeds that contain a tolerance to certain pesticides
could be used without the need for tillage because those crop
protection products could be applied over the top of the seeds without
damaging them. With this new option in place, farmers replace intense
tillage previously required for control with conservation tillage
practices. Conservation tillage, defined as tillage systems leaving at
least 30 percent of the soil surface covered by crop residue at crop
planting, has now been widely adopted by farmers around the country.
The use of these practices substantially reduces soil erosion. GMOs
also reduce the amount of pesticides that need to be sprayed. Over the
last 20 years, this technology has reduced pesticide applications by
8.2 percent and helped increase crop yields by 22 percent.
Maintaining access to innovative and effective products, including
transgenic seeds and pesticides, is important for enabling agriculture
to be part of the solution for global climate challenges. First,
farmers using conservation tillage practices make fewer trips over
their field over the course of a growing season, thus reducing energy
consumption. Second, plants are known consumers of carbon dioxide,
pulling it out of the atmosphere and storing it in the soil through
their roots. Tillage breaks up the soil carbon which is then released
back into the atmosphere. If farmers must revert to using heavy tillage
to control weeds, agriculture will likely decrease its ability to
capture and store carbon in the soil and, therefore, decrease its
ability to positively address climate change.
Decarbonization From Renewable Fuels
NCGA supports the Renewable Fuel Standard (RFS), the only Federal
statutory GHG reduction requirement. The RFS provides low carbon
biofuels access into the closed transportation fuel market. Recent EPA
administration of the RFS, with extensive waivers for refineries for
biofuels blending, reduces renewable fuel demand and the emissions
reductions provided by biofuels. NCGA supports upholding the integrity
of the RFS to further reduce emissions in the transportation sector.
The RFS has exceeded projections and resulted in cumulative carbon
reduction savings of 980 million metric tons since 2007, due to greater
than expected savings from conventional ethanol and despite lower than
expected production of next generation fuels.
The transportation sector accounts for nearly a third of the
nation's GHG emissions. Near-term achievable emissions reductions from
this sector should be prioritized by increasing use of renewable fuels.
Federal LCA models show that conventional ethanol's carbon footprint is
shrinking, allowing renewable fuel use to contribute to greater
decarbonization of transportation fuel.
The RFS requires renewable fuels to meet lifecycle GHG emission
reduction thresholds. Models used to predict RFS impacts in 2010
projected that use of conventional ethanol would reduce GHG emissions
by 21 percent compared to gasoline by 2022. However, updated analysis,
based on actual corn and ethanol production, shows much greater GHG
reductions than projected. As a result, corn-based ethanol is
delivering far more GHG reductions today than anticipated in the RFS.
Ethanol's carbon footprint is shrinking due to advances in both
corn and ethanol production. A 2018 USDA study shows that ethanol
results in 39 to 43 percent fewer GHG emissions than gasoline. Building
on this progress, additional improvements on farms and in ethanol
production supported by expanding markets for low carbon fuels could
result in ethanol with up to 70 percent fewer GHG emissions than
gasoline, according to USDA's analysis.
The GREET model measures lifecycle emissions of transportation
fuels and is considered the ``gold standard'' in lifecycle analysis.
Updated annually, GREET shows steady improvement in corn ethanol's
lifecycle GHG profile, with corn-based ethanol's carbon intensity (CI)
currently about 41 percent below that of baseline gasoline, following
steady improvement since 2010, when GREET showed ethanol's CI about 19
percent below that of gasoline.
Furthermore, according to California Air Resources Board (CARB)
data, the CI of ethanol under the state's Low Carbon Fuel Standard
(LCFS) is more than 30 percent lower today than it was in 2011 and at
least 40 percent lower than the CI of gasoline. These significant
improvements in ethanol's carbon intensity are the result of
advancements and wider adoption of more efficient farming practices,
improved efficiency in ethanol production and increased crop
productivity that efficiently uses existing crop land and is not
producing land cover change. For example, Argonne's recent updates to
the GREET model incorporate the growing adoption of reduced tillage and
no-tillage practices into the LCA for ethanol.
NCGA strongly supports using Argonne's GREET model as the basis for
updated and accurate measurement of the decarbonization conventional
ethanol provides in the transportation sector. With the benefit of
real-world data on crop and ethanol production through the expansion of
renewable fuels production since 2005, LCA should be based on
experience, not estimates or projections. These updates to the LCA show
that corn-based ethanol is far exceeding the GHG emissions reductions
required and expected under the RFS.
Although electric vehicles have gained market penetration, liquid
fuel powered vehicles will remain the dominant vehicle type for the
foreseeable future. According to U.S. Energy Information
Administration's 2020 Energy Outlook, gasoline and flex-fuel vehicles
will make up 81 percent of vehicle sales in 2050. With continued use of
liquid fuel vehicles, continued decarbonization can be accomplished
through greater use of biofuels such as ethanol. NCGA views biofuels
such as ethanol as a key part of the solution for further decarbonizing
the transportation sector.
Low Carbon Octane Standard for Fuel Efficiency and Decarbonization
Matching new engine technologies with improved transportation fuels
would make vehicles more fuel efficient and reduce emissions further.
Establishing a Low Carbon Octane Standard (LCOS) for light duty vehicle
fuel would reduce GHG emissions, improve fuel efficiency, improve air
quality and further diversify the fuel supply--all while maintaining
fuel and vehicle affordability and choice for drivers.
In the 116th Congress, Representative Cheri Bustos, an Agriculture
Committee Member, introduced the Next Generation Fuels Act, legislation
to establish a low carbon, high octane standard for fuel. This
legislation would establish a minimum fuel octane standard of 98
Research Octane Number, or RON, for motor gasoline paired with a
requirement that sources of additional octane result in at least 30
percent fewer GHG emissions than baseline gasoline and removal of
barriers to higher ethanol blends.
This low carbon, high octane fuel allows automakers to use advanced
engine design features that increase engine performance and
significantly improve fuel efficiency. These engine design features,
such as higher compression ratios, are limited by current fuels because
low octane fuels cannot mitigate engine knock. High octane fuel limits
knock, enabling automakers to design more fuel efficient vehicles,
leading to lower GHG emissions. Current fuel standards limit the use of
these advanced engine technologies and leave automakers with fewer
options to meet higher fuel economy standards.
Demonstrated through significant research, high octane fuel such as
98 RON supports fuel efficiency gains of five percent or more, and
increased fuel efficiency reduces greenhouse gas emissions. By
requiring that a fuel used to enhance octane also reduces GHG emissions
compared with unblended gasoline, a LCOS further decarbonizes liquid
fuels as vehicle technologies advance.
According to Department of Energy's analysis, because of ethanol's
high octane rating, a low carbon, high octane mid-level ethanol blend
would provide significant GHG reduction benefits through both increased
vehicle efficiency and by offsetting petroleum with lower emissions
renewable fuel. Priced lower than unblended gasoline, ethanol is the
most cost-effective octane source, providing the greatest efficiency
gains at the lowest cost to drivers. A 98 RON E25 blend, for example,
would provide a further GHG reduction from additional ethanol
offsetting petroleum on top of the GHG reduction from the fuel
efficiency gains. We look forward to working on the Next Generation
Fuels Act in the 117th Congress, demonstrating how agriculture can
contribute to addressing climate change through the use of more low
carbon renewable fuels, and carbon sequestration through sustainable
farming practices.
NCGA stands ready to assist this Committee as it carves a path
forward on this important policy issue. Thank you again for the
opportunity to provide this statement for the record.
Sincerely,
John Linder,
President,
National Corn Growers Association.
Letter 3
on behalf of julia olson, executive director, our children's trust
February 23, 2021
Chair Spanberger and Ranking Member LaMalfa, Full Committee on
Agriculture
Re: Materials for February 25, 2021 Hearing on Climate Change and
the U.S. Agriculture and Forestry Sectors
Dear Chair Spanberger and Ranking Member LaMalfa,
On behalf of Our Children's Trust (``OCT''), a nonprofit
organization dedicated to securing the legal right to a stable climate
system for youth and future generations, please find enclosed herewith
materials for your consideration relevant to the House Committee on
Agriculture's February 25, 2021 hearing, ``Climate Change and the U.S.
Agriculture and Forestry Sectors.'' This submission will inspire you
with the stories of courageous children and provide resources critical
to developing science-based, technically and economically feasible
solutions to the climate crisis.
Through youth-led constitutional legal actions, including Juliana
v. United States (``Juliana'')--the landmark Federal constitutional
climate case filed by twenty-one youth plaintiffs, including eleven
Black, Brown and Indigenous youth--OCT supports youth seeking to hold
their governments accountable for policies and actions that have
caused, and continue to cause, the climate crisis. Through these
actions, youth seek science-based remedies to reduce greenhouse gas
emissions at rates necessary to protect their fundamental human rights.
It is OCT's understanding that the materials submitted for the
February 25th hearing will inform the Committee's outlook on climate
impacts and future climate policy and legislation on sustainable
practices in the agriculture and forestry sectors as it works in tandem
with President Biden's bold actions to combat the climate crisis. Given
our mission, OCT has a substantial interest in ensuring that any such
legislation is consistent with what the best available science dictates
is necessary to stabilize the climate system and protect the
fundamental rights of youth and future generations.
We invite you to consult the materials enclosed herewith, which
demonstrate that climate change is already harming the fundamental
rights of young people in the United States and legislation which
ensures emissions reductions and sequestration of excess CO2
is necessary for the protection of the fundamental rights of American
children. Please note in Exhibit D below, the prescription to stabilize
the atmosphere is a return to atmospheric CO2 levels to 350
ppm by 2100, limiting global warming to less than 1 Celsius by 2100.
This requires that net negative CO2 emissions be achieved
before mid-century.
Specifically, enclosed as Exhibit A is a summary of the Juliana
case, including plaintiffs' profiles. Enclosed as Exhibit B you will
find impact statements of youth from the Federal case supported by OCT,
Juliana v. United States, which demonstrates some of the profound ways
that climate change is already affecting the fundamental rights of
young people, including youth of color and indigenous youth in
frontline and vulnerable communities. Jacob Lebel and Alex Loznak's
family farms in Oregon have been impacted by increased heat waves and
drought conditions, wildfire, and pest infestations. Due to drought,
water scarcity and failed attempts at dryland farming, Jamie Butler's
family moved away from their traditional lands and home on the Navajo
Nation Reservation in Arizona.
Enclosed as Exhibit C is the expert report of Dr. G. Philip
Robertson, University Distinguished Professor of Ecosystem Ecology in
the Department of Plant, Soil and Microbial Sciences at Michigan State
University and Scientific Director for the Department of Energy's Great
Lakes Bioenergy Research Center at the University of Wisconsin and
Michigan State University. This expert report estimates the potential
for increased carbon sequestration from U.S. forest, range, and
agricultural land management. Dr. Robertson concludes:
Over the period 2020 to 2100, changes to land management
practices in the U.S. could mitigate . . . over 30% of the
negative and avoided emissions needed, after phasedown of
fossil fuel emissions, to return Earth's atmosphere to a more
stable state.
Avoiding tillage with no-till technology is one well-
recognized practice to rebuild soil carbon . . . Adding winter
cover crops to avoid bare soil for most of the year can
increase soil carbon, as can diversifying crop rotations . . .
and applying compost or manure. Growing perennial grasses or
trees on degraded or low value agricultural soils can also
result in significant carbon gains.
On pastures and rangeland, soil carbon storage can be
improved by increasing plant productivity via improved plant
species and by avoiding overgrazing via careful attention to
the number of livestock per acre. About 43% of all pasture and
rangeland in the U.S. is managed by Federal agencies.
Forests can also be managed to enhance carbon sequestration
in trees and soil. Faster growing species accumulate more
carbon over their lifetimes and therefore planting more of
these species will store more carbon in wood, as will growing
trees in longer rotations (the number of years between
harvests) . . . About 42% of all forestland in the conterminous
U.S. is managed by Federal agencies.
Enclosed as Exhibit D you will find a document entitled
``Government Climate and Energy Actions, Plans, and Policies Must Be
Based on a Maximum Target of 350 ppm Atmospheric CO2 and 1
C by 2100 to Protect Young People and Future Generations.'' This
document details the scientific basis underlying, and prescription for,
stabilization of the climate system as necessary to protect the
fundamental human rights of youth and future generations relative to
the climate crisis and explains that allowing warming of up to 1.5 C
is not safe.
Enclosed as Exhibit E include reports published by the energy
experts at Evolved Energy Research. Exhibit E.1 is an executive summary
entitled ``350 PPM Pathways for the United States,'' which demonstrates
multiple technologically and economically feasible pathways for
transitioning to a 100 percent clean energy economy consistent with the
science-based prescription for stabilizing the atmosphere and securing
the fundamental rights of youth and future generations. The report
demonstrates multiple technically and economically feasible pathways
for transitioning to a 100 percent clean energy economy consistent with
the science-based prescription for stabilizing the climate system and
securing the fundamental rights of youth and future generations. The
pathways reduce greenhouse gas emissions in the United States at a rate
consistent with returning global concentrations of CO2 in
the atmosphere to 350 ppm by 2100, limiting global warming to less than
1.0 C by 2100. This requires that net negative CO2
emissions be achieved before mid-century. The report provides important
policy guidance to achieve this steep and necessary level of emissions
reductions in the United States. Enclosed as Exhibit E.2 is an
executive summary entitled ``350 PPM Pathways for Florida'' that
mirrors the national study's target. Updated national data is included
in the full report as the U.S. model was upgraded to reflect the newer
and even lower costs for renewable technologies. The U.S. data from the
Technical Supplement (page 71) is also included under this Exhibit.
Legislation which ensures emissions reductions and sequestration of
excess CO2 consistent with what the best available science
dictates is necessary for the protection of the fundamental rights of
young people and future generations. The information in these Exhibits
are additionally relevant to a forthcoming reintroduction of a House
concurrent resolution on Children's Fundamental Rights and Climate
Recovery \1\ supporting the Juliana youth plaintiffs. It recognizes the
disproportionate effects of the climate crisis on children and their
fundamental rights which demands renewed U.S. leadership and
development of a national, science-based climate recovery plan. This
resolution, sponsored by Representative Schakowsky and originally
introduced in September 2020, had the support of 61 cosponsors from
both chambers.
---------------------------------------------------------------------------
\1\ https://www.congress.gov/bill/116th-congress/house-concurrent-
resolution/119?r=1&s=6.
---------------------------------------------------------------------------
Should you have any questions regarding the enclosed materials,
please feel free tocontact Liz Lee, OCT's government affairs staff
attorney at [Redacted].
Sincerely,
Julia Olson,
Executive Director,
Our Children's Trust.
Exhibit A: Juliana v. United States Summary and Plaintiffs' Profiles
Juliana v. United States
Young Americans Fight for Their Constitutional Rights and Climate
Recovery
Background
Represented by attorneys at Our Children's Trust,\1\ 21 young
Americans filed their constitutional climate lawsuit, Juliana v. United
States, against the Executive Branch of the U.S. Government in 2015.
They assert that the government's affirmative actions causing climate
change have violated their constitutional rights to life, liberty,
property, and equal protection of the laws, and impaired essential
public trust resources. They seek a court-ordered, science-based
climate recovery plan, to put the U.S. on track to bring atmospheric
carbon dioxide levels back to 350 parts per million (ppm) by 2100,
which would limit long-term warming to less than 1 C, which scientists
say is the safe target to stabilize the planet's climate system.
---------------------------------------------------------------------------
\1\ https://www.ourchildrenstrust.org/.
---------------------------------------------------------------------------
In May 2019, a team of renowned energy experts, Jim Williams, Ben
Haley, and Ryan Jones, published a report \2\ that demonstrates the
technical and economic viability of the U.S. to meet this standard by
2100. An October 2020 report \3\ on specific pathways for Florida to
meet this standard also provides updated U.S. data.
---------------------------------------------------------------------------
\2\ https://www.ourchildrenstrust.org/350-ppm-pathways.
\3\ https://www.ourchildrenstrust.org/350-ppm-pathways-florida.
---------------------------------------------------------------------------
History
The U.S. District Court has repeatedly found that the youth
plaintiffs have legitimate claims for trial. In a groundbreaking
decision in November 2016, the court found that the U.S. Constitution
secures the fundamental right to a climate system capable of sustaining
life; that plaintiffs' injuries give them standing to bring their
claims; and that the Court has authority to remedy the youth's
injuries.
Since that historic ruling, the defendants have relentlessly
attempted to prevent Juliana v. U.S. from going to trial. Three times
in 2018, the Ninth Circuit Court of Appeals ruled resoundingly against
government attempts to stop the case. The U.S. Supreme Court has also
ruled in favor of the youth, twice refusing to halt the case.
On January 17, 2020, a divided panel of the Ninth Circuit Court of
Appeals found for the plaintiffs in nearly every respect, but
ultimately ruled that the courts cannot stop the Executive Branch of
government from harming children with its policies that cause climate
change. The plaintiffs filed a petition for rehearing on March 2, 2020,
supported by ten amicus curiae briefs, including 24 Members of Congress
and constitutional law experts.
Looking Forward
On February 10, 2021, while a judge requested a vote, the Ninth
Circuit denied the plaintiffs' request to rehear their lawsuit without
explanation. Plaintiffs are now planning to seek review in the U.S.
Supreme Court. The plaintiffs are also requesting that the Biden-Harris
Administration and the Department of Justice meet with the plaintiffs
to discuss settling their claims, and thereby protect their rights and
the rights of children to come.
Support These Brave Plaintiffs
The youth plaintiffs deserve to have their constitutional claims
heard, and need your support now. Please publicly support their right
to have their constitutional claims upheld in a court of law. Support
the Congressional resolution recognizing children's fundamental rights
and the need for a national, science-based climate recovery plan at
ourchildrenstrust.org/congressionalresolution. The resolution,
originally introduced on September 23, 2020, was supported by 63
Members of Congress. Also, join future amicus curiae briefs in support
of their constitutional rights and the judiciary exercising its Article
III powers in their case. Show our nation's children you care about
their future, and the future of all generations to come.
Juliana v. United States: Meet the Plaintiffs
Meet all 21 Juliana plaintiffs at ourchildrenstrust.org/
federal-plaintiffs
Learn more about their stories in this 60 Minutes \4\ segment
(bit.ly/60minsjuliana) and their visit to Congress in this
video \5\ (bit.ly/yearsprojectjuliana) from The YEARS Project
---------------------------------------------------------------------------
\4\ https://www.youtube.com/watch?v=C1g2K4DRxLo&feature=emb_title.
\5\ https://www.youtube.com/watch?feature=youtu.be&v=sd5K1ms1tOc.
For over 5 years, these young plaintiffs, all of whom have been
personally impacted by climate change, have been leading the game-
changing litigation campaign to secure the legal right to a stable
climate for young people, based on the best available science. In 2015,
they filed their constitutional climate lawsuit against the U.S.
government in the U.S. District Court for Oregon.
Kelsey Juliana, 24, Eugene, OR
Fighting climate change since she was
10, Kelsey has been increasingly
exposed to hazardous wildfire smoke in
her hometown. As a teenager, she
participated in the Great March for
Climate Action, marching 1,600 miles
from Nebraska to D.C. Time Magazine
recognized Kelsey as a Rising Star in
its list of the Next 100 Most
Influential People in the World.
Vic Barrett, 21, White Plains, NY
A Garifuna American, Vic has spoken
about environmental justice issues and
how his climate anxiety is increased
because his identities--first
generation, trans, indigenous, Latinx,
Black, youth--make him uniquely
vulnerable to the climate crisis. In
2019, he testified at a historic joint
hearing of the House Foreign Affairs
and Select Committee on the Climate
Crisis alongside Greta Thunberg.
Jaime Butler, 20, Flagstaff, AZ
Jaime is of the Tangle People Clan,
born of the Bitterwater Clan. She grew
up in Cameron, Arizona on the Navajo
Nation Reservation, but had to move due
to water scarcity and failed attempts
at dryland farming. Jaime knows
firsthand the cultural and spiritual
impacts of climate change as she and
her tribe struggle to participate in
their traditional ceremonies due to
climate-related impacts.
Levi Draheim, 13, Satellite Beach, FL
Levi has lived most of his life on a
barrier island in Florida, barely above
sea level and literally washing away
due to sea level rise and storms made
worse by climate change. In 2019, Levi
addressed a youth stakeholder's meeting
with Members of the Senate Democrats'
Special Committee on the Climate Crisis
at the United Nations Foundation. His
baby sister is a source of motivation
and inspiration.
Xiuhtezcatl Martinez, 20, Boulder, CO
Xiuhtezcatl is a renowned hip-hop
artist and activist. He is also the
former Youth Director and now Co-Chair
of the executive board for Earth
Guardians. He has experienced extreme
weather events that have been
exacerbated due to climate change, such
as catastrophic flooding. Raised in the
Aztec tradition, Xiuhtezcatl has spoken
at the United Nations several times,
including in English, Spanish, and his
Native language, Nahuatl.
Exhibit B: Impact statements for plaintiffs_Jacob Lebel, Alex Loznak,
and Jamie Butler
------------------------------------------------------------------------
------------------------------------------------------------------------
Julia A. Olson (OR Bar 062230) Joseph W. Cotchett
[email protected] [email protected]
Wild Earth Advocates Philip L. Gregory (pro hac vice)
1216 Lincoln Street [email protected]
Eugene, OR 97401 Paul N. McCloskey
Tel: (415) 786-4825 [email protected]
Cotchett, Pitre & McCarthy, LLP
Daniel M. Galpern (OR Bar 061950) San Francisco Airport Office Center
[email protected] 840 Malcolm Road
Law Offices of Daniel M. Galpern Burlingame, CA 94010
1641 Oak Street Tel: (650) 697-6000
Eugene, OR 97401 Fax: (650) 697-0577
Tel: (541) 968-7164
Attorneys for Plaintiffs
United States District Court
District Of Oregon
Eugene Division
Kelsey Cascadia Rose Juliana; Case No.: 6:15-cv-01517-TC
Xiuhtezcatl Tonatiuh M., through
his Guardian Tamara Roske- Declaration of Jacob Lebel In
Martinez; et al., Support of Plaintiffs' Opposition
Plaintiffs, to Defendants' Motion to Dismiss;
v.
The United States of America; Oral Argument: February 17, 2016,
Barack Obama, in his official 2:00 p.m.
capacity as President of the
United States; et al.,
Federal Defendants.
------------------------------------------------------------------------
I, Jacob Lebel, hereby declare as follows:
1. I am an eighteen-year-old resident of Roseburg, Oregon and a
United States citizen. In 2001, I moved with my family from Quebec,
Canada to Roseburg. We came to the West Coast to find a place of
natural beauty and mild weather where we would be able to start a farm
and live a sustainable lifestyle.
2. I am currently a 3.9 GPA student at Umpqua Community College and
Vice-President of the College's Environmental Sustainability Club.
3. My family founded Rose Hill Farms in Roseburg, Oregon. The Farm
extends over 350 acres, providing milk, eggs, meat, vegetables, fruits,
nuts, and products such as wool and timber to me, my family, and
members of the local community. Our animal breeding programs help
preserve endangered and unique heritage livestock breeds. The Farm is
currently transitioning towards meeting all of its energy needs through
solar and hydroelectric power produced onsite.
4. I intend to continue working and living on the Farm as an adult
and I currently take an active role in managing and growing the
business. Thus, the economic future and sustainability of the Farm is
very closely tied to my own future. The Farm provides me with fresh,
healthy food and recreational opportunities and I would like to see my
own children in the future have these same benefits.
5. My connection to the Oregon wilderness and to Rose Hill Farms is
deeply personal. As a child, I was homeschooled and spent most of my
free time playing in the fields and forests around our house. Family
trips included swimming in the South Umpqua and hiking the forests
around Crater Lake, Mount Thielsen, and Toketee Falls. As a teenager, I
wrote poetry and composed songs drawing on the natural beauty that
surrounded me on the Farm.
6. My recreational and aesthetic interests are harmed by
Defendants' actions to continue producing greenhouse gases at a
dangerous rate. I regularly see bird species on the Farm, such as the
American Bald Eagle, the Allen's Hummingbird, the Spotted Owl, and the
Ruffed Grouse. These species are seeing their survival threatened by a
changing climate and their range may no longer extend to Douglas
County. Drought conditions and wildfire activity also severely affect
the plant biodiversity in Oregon, as well as the state's rivers,
watersheds, and snowpack.
7. Defendants' enabling of and lack of action against climate
change have created an unsafe climate for the future of Rose Hill
Farms. In the summer of 2015, Douglas County experienced two major
wildfires: the Cable Crossing and Stouts Creek Fires. Combined, these
fires burnt 28,000 acres. The massive smoke cloud from the Stouts Creek
Fire was clearly visible from my family's Farm. Smoky and hazy skies
became a norm for me during the summer of 2015, affecting my enjoyment
of outside work and hiking on my family's Farm. This was compounded by
record temperatures and heat waves that stressed the garden crops and
livestock and increased my workload, while also making it harder and
more dangerous to work long hours in the heat.
8. Rose Hill Farms contains seven permanent structures and three
greenhouses. These structures include the house where I grew up and
currently live and a cabin hand built out of wood harvested from our
own forests and milled in our workshop. As a young adolescent, I helped
lay planking on the walls and roof and varnish the structure. This
cabin and our entire infrastructure is now at heightened risk from
increased wildfire activity in Douglas County.
9. Approximately four-hundred fruit and nut trees grow on our Farm,
many of them over thirteen years old. I take special pleasure in
walking through the groves of Asian pear and peach trees and picking
ripe figs and pomegranates from our plantations. As a small boy, I
helped plant many of these trees and they are part of the heritage I
want to pass on to my children. In addition to the spiritual and
aesthetic meaning these orchards have for me, they represent a
significant economic asset for my family and me, bringing in roughly
$20,000 in revenue every year.
10. In the past 4 years, Rose Hill Farms has experienced an
infestation of a new invasive insect pest called the Spotted-Wing
Drosophila (Drosophila Suzukii). The Suzuki fly, which lays its eggs in
unripe soft fruits, has become a serious problem for the entire
Northwest fruit and berry industry. A warmer climate promotes the
spread of the Suzuki fly population and other insect pests by
increasing their metabolisms and allowing them to overwinter safely.
Weather extremes, such as droughts in summer and heavy rains in spring
and winter, also stress the fruit trees and decrease their ability to
defend themselves from fungal infections and pest attacks. Since the
Suzuki fly infestation started, I have had to put in extra hours of
labor each summer in order to cope with the increasing frequency of
sprays needed to protect the crops.
11. As a result of the Suzuki fly invasion, the Farm has incurred
crop losses to our nectarine, peach, and cherry orchards, amounting to
approximately $20,000. More gravely, due to their foreign qualities,
there is currently no organically approved pesticide that effectively
combats these particular pests without relying on a repetitive usage
leading to resistance. For the first time, we have been forced to spray
non-organically approved pesticide on our trees in order to save the
crops. This spraying prevents us from attaining organic certification
on any farm products for 5 more years after we stop using this
pesticide and represents an incalculable loss of profit from our
operation.
12. Rose Hill Farms contains five ponds that fill from rainfall and
groundwater during the winter and provide all the water for our
livestock, gardens, and orchards during the summer. During the summer
of 2015, for the first time in the 10 years since the ponds were
excavated, I watched them run dry due to drought conditions. We were
forced to ration irrigation water during a summer which saw the highest
June temperatures ever recorded across Oregon.
13. Water shortages due to drought conditions have forced my family
to begin implementing an extended water collection and irrigation
system, which includes three additional ponds and a large scale solar
pumping and water transport system. Costs for the project are projected
to reach $15,000.
14. I also enjoy winter recreation and sports, including
snowboarding, sledding, and hiking in the snow. Having spent the first
3\1/2\ years of my life in Canada, recreating in cold weather and deep
snow with my family helps me reconnect with my roots. I learned to
snowboard at the Mount Hood ski resort and retain magical memories of
soaking in the snowy outdoor spa and pool and enjoying the breathtaking
winter vistas.
15. Rising global temperatures caused by Defendants as set forth in
our Complaint are already affecting my ability to enjoy activities that
require snow. Due to an historic lack of snow last year, the Mt.
Ashland ski resort remained closed throughout the winter of 2014, Mount
Hood received record low snowfall, and the Willamette Pass resort was
only open for a handful of days. That winter, we had been planning a
skiing/snowboarding trip to the Willamette Pass Resort, which we were
forced to cancel.
16. Every year since 2010, my family has rented a cabin in Bandon
on the Oregon coast for several days to a week. During these annual
visits, I enjoy walking the shoreline and exploring the caves exposed
by low tide. I want to be able to bring my own children to marvel at
the sea stars and crabs in tidal pools. However, due to rising sea
levels and changing ecology, this stretch of coastline and many of the
species that inhabit it will not be available for recreation and
enjoyment by my family and me.
17. I vividly remember going on my first crabbing trip. The
excitement of reeling in a pot full of the brilliantly colored
crustaceans and then being able to cook and eat them fresh off the boat
was unprecedented for me. This opening of the 2015 Dungeness crab
season in Oregon was unusually delayed from its usual December 1st date
and was still closed on Jan 3rd. In California, the crab season
traditionally starts even earlier (on November 15th); it also has yet
to open. This has been officially attributed to an unprecedented toxic
algae bloom triggered by warmer ocean temperatures. Ocean acidification
is endangering the survival of the crabs and all the shelled seafood
that I consume.
18. In addition to crab fishing, which I intend to continue if
possible, my family and I receive monthly deliveries of fresh seafood
from Port Orford Sustainable Seafood. These deliveries form an integral
part of my regular diet and include Dungeness crab and clams. This
winter we were told there would be no crab available for Christmas.
19. My family and I also often procure a permit to harvest mussels
from seashore rocks in Bandon, Oregon. However, algae bloom biotoxins
are forcing Oregon officials to restrict mussel harvesting for longer
and longer periods. It is not easy for me to find a time for a seaside
trip when the mussels are safe to eat. Furthermore, oyster, mussel, and
clam populations are already shrinking due to ocean acidification and
lack of oxygen. The effects of ocean acidification and ocean warming
stemming from Defendants' actions are already affecting my food supply
and my ability to personally participate in activities such as crab-
fishing and mussel gathering.
20. The expansion and creation of new fossil fuel infrastructure,
such as the proposed Jordan Cove Project in Southern Oregon, conducted
as a result of Defendant's energy policies, also threaten my family's
Farm and my way of life.
21. The border of the Farm is located approximately 1 mile from the
route of the proposed Pacific Connector Pipeline. If built, the
pipeline and the associated 100-150 wide clear-cut may be visible from
scenic points on the Farm where I regularly hike. This would cause me
significant emotional distress and harm my enjoyment of the Farm.
22. According to testimony by oyster farmers such as Lili Clausen
of Coos Bay, silt and water conditions that would be created by
construction of the Pacific Connector Pipeline and Jordan Cove
liquification factory would harm oyster beds. The oysters that I eat
are mostly bought locally in Coos Bay and construction of this project
would harm this important food supply.
23. If built, Jordan Cove would be the single biggest emitter of
greenhouse gases in Oregon once the Boardman Coal-Fired Power Plant
closes in 2020. The pipeline would require a clearcut through old-
growth, carbon sequestering forests. This project would contribute to
climate change and worsen its impacts on my life.
24. The danger of explosions along the length of the Pacific
Connector Pipeline would heighten the risk of a wildfire starting
nearby to our Farm. Williams Pipeline, the company that would build the
pipeline, has already had four explosion incidents on its pipelines and
facilities. Coupled with already severe fire seasons and drought
conditions, the Pacific Connector Pipeline would put my family's Farm
in constant danger. These extreme climate conditions created by
Defendants and the continuation of fossil fuel production projects such
as Jordan Cove are harming my daily life as well as my future ability
to enjoy and sustain myself.
I certify under penalty of perjury in accordance with the laws of
the State of Oregon, and to the best of my knowledge, that the
foregoing is true and correct.
Dated this 5th day of January, 2016 at Roseburg, Oregon.
Jacob Lebel.
------------------------------------------------------------------------
------------------------------------------------------------------------
Julia A. Olson (OR Bar 062230) Joseph W. Cotchett
[email protected] [email protected]
Wild Earth Advocates Philip L. Gregory (pro hac vice)
1216 Lincoln Street [email protected]
Eugene, OR 97401 Paul N. McCloskey
Tel: (415) 786-4825 [email protected]
Cotchett, Pitre & McCarthy, LLP
Daniel M. Galpern (OR Bar 061950) San Francisco Airport Office Center
[email protected] 840 Malcolm Road
Law Offices of Daniel M. Galpern Burlingame, CA 94010
1641 Oak Street Tel: (650) 697-6000
Eugene, OR 97401 Fax: (650) 697-0577
Tel: (541) 968-7164
Attorneys for Plaintiffs
United States District Court
District Of Oregon
Eugene Division
Kelsey Cascadia Rose Juliana; Case No.: 6:15-cv-01517-TC
Xiuhtezcatl Tonatiuh M., through
his Guardian Tamara Roske- Declaration of Alexander Loznak In
Martinez; et al., Support of Plaintiffs' Opposition
Plaintiffs, to Defendants' Motion to Dismiss;
v.
The United States of America; Oral Argument: February 17, 2016,
Barack Obama, in his official 2:00 p.m.
capacity as President of the
United States; et al.,
Federal Defendants.
------------------------------------------------------------------------
I, Alexander Wallace Loznak, hereby declare as follows:
1. I am a nineteen-year-old Oregon resident, a United States
citizen, and a Plaintiff in this action. My family lives on the Martha
A. Maupin Century Farm in the unincorporated rural area of Kellogg,
Oregon.
2. My Educational Background: I graduated as one of the
valedictorians of the Class of 2015 at Roseburg High School in
Roseburg, Oregon, and I am currently an undergraduate student at
Columbia University in New York City. In the summer of 2014, I attended
The American Legion's Oregon Boys State program. At Boys State, I was
awarded an academic scholarship from The American Legion and Samsung
``[f]or excellence in academic pursuits and dedication to the
community, attributes which are in keeping with the efforts of the U.S.
service men and women who helped maintain freedom for the citizens of
South Korea.''
3. My History of Climate Advocacy: Fighting climate change is one
of the central objectives of my life. I chose to attend Columbia
University to have an impact on issues of global significance,
including the climate crisis. In my application to Columbia, I stated
``young people--who will inherit either a broken world or a vibrant
one--must take the lead'' in addressing climate change.
4. In Oregon, I have advocated for local solutions to the climate
crisis. I started the Climate Change Club at Roseburg High School, and
the League of Umpqua Climate Youth (``LUCY''), with the goal of
installing solar panels at Roseburg High School.
5. I have lobbied Oregon state legislators to pass House Bill 3470,
which would create market-based incentives to reduce carbon dioxide
emissions. Additionally, I have advocated for Federal policies to
curtail climate change. In the summer of 2013, I wrote a letter to
President Obama, asking him to take comprehensive action to limit
fossil fuel extraction and carbon dioxide emissions. A true and correct
copy of my letter to the President is attached as Exhibit 1.*
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* Editor's note: Exhibit 1 was not included in Our Children's Trust
submission for the record of the hearing.
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6. My Opposition to Jordan Cove: I am actively opposed to the
construction of the Pacific Connector Natural Gas Pipeline and the
Jordan Cove Energy Project. In November 2013, I wrote an op-ed in the
Roseburg News-Review to advocate that the Douglas County Planning
Commission deny a permit for the pipeline. In December 2014, I spoke in
opposition to the pipeline at a Federal Energy Regulatory Commission
hearing in Roseburg.
7. The Effects of Climate Change on My Family's Farm: The Martha A.
Maupin Century Farm, my permanent residence, contains 570 acres of land
and sits along the Umpqua River. My great-great-great-great-
grandmother, Martha Poindexter Maupin, founded the farm in 1868 after
crossing the Oregon Trail. This farm is one of the few Century Farms in
Oregon named for a woman.
8. My grandmother, Janet Fisher, is the current owner of the farm.
In 2014, my grandmother had a book published by Globe Pequot Press
about Martha's life, A Place of Her Own: The Legacy of Oregon Pioneer
Martha Poindexter Maupin. The book describes Martha's experience when
she discovered the Kellogg Crescent area along the Umpqua River, where
the farm is located: ``She nudged her horse and rode over a gentle rise
across a saddle of land to a broad overlook. Her breath caught. She
could see the valley, the river, a plain on the far side, and mountains
beyond. A breeze stirred, like a whisper saying, `Come.' ''
9. The farm is my intellectual and spiritual base, and a
foundational piece of my life and heritage. My family has passed the
farm from generation to generation, and my identity and well-being
depend on the preservation and protection of the farm. I want to
explore the farm with my children someday, and I plan to eventually
move back to the farm. Unfortunately, drought conditions, unusually hot
temperatures, and climate-induced migration of forest species are
harming and will increasingly harm my use and enjoyment of the Martha
A. Maupin Century Farm.
10. Agricultural produce from the farm is an important source of
revenue and food for my family and me. Because I am a student with
little income, my financial survival depends in large part on the
continued productivity of the farm. On the farm, my family grows timber
trees, plum trees, and hazelnut trees. We rent pasture for grass-fed
beef cattle. We also have a large garden, in which we grow many of the
fruits and vegetables that we consume. We raise chickens for eggs we
consume. Climate change, caused in substantial part by the Federal
Defendants, adversely impacts the productivity of the farm and
threatens my financial survival.
11. How Defendants Are Harming My Use of the Farm: Recordsetting
heat waves, drought, and fire in the region of my farm, caused in
substantial part by the Federal Defendants, harm my ability to work
outside on the farm during the summer months. The heat waves and
drought adversely impact the productivity of the farm, especially my
family's hazelnut orchard and timber trees.
12. Exact temperature records are not available for the farm, but
the temperature at the farm is usually very close to the temperature in
Roseburg, Oregon. According to the National Weather Service, the
average temperature in Roseburg for summer 2015 (June through August)
was 74 Fahrenheit, making it the hottest summer ever recorded there.
The two previous records were 71.8 and 71.6, set in 2014 and 2013
respectively.
13. July 30, 2015 tied the record for the hottest day ever recorded
in Roseburg, with a high of 108 Fahrenheit. June 27, 2015 set the
record for the highest-ever low temperature. That means at night, the
lowest it got was 74. The lowest temperature at night had never been
so high. At the end of June 2015, temperatures repeatedly exceeded
100.
14. Drought came with the heat, and on June 11, 2015, Governor
Brown declared a drought emergency for Douglas County, where Roseburg
and the farm are located.
15. In 2011 and 2012, my family planted a 7 acre hazelnut orchard
on the farm, in the fertile plain next to the Umpqua River. Hazelnuts
have historically grown well in Oregon, and according to the Oregon
Hazelnut Growers Office, our state produces 99% of the U.S. hazelnut
crop. Planting the orchard on our farm required an investment of about
$7,400.00 in capital costs. We also planted two new acres of plums,
which required an investment of just over $1,000.00 in capital costs.
The planting was also an investment of time and energy, and I dug holes
in the ground for many of the baby trees. We have plans to plant as
many as 15-20 additional acres of hazelnut trees in the future.
Unusually hot temperatures and drought conditions, caused in
substantial part by the Federal Defendants, adversely impact the health
of the existing hazelnut orchard and diminish the viability of any
additional plantings.
16. Record-setting heat in the summer of 2015 caused our new
hazelnut trees on the farm to wither. The orchard is not irrigated, so
my father and I had to provide more water than usual. We watered the
trees one at a time with a tractor, which required considerable added
man-hours of labor. Based on information from the late Jeff Olsen, a
former horticulturist from Oregon State University, we had not expected
to need to water the hazelnut trees that were planted in 2012 at all in
2015. We believed that the trees planted in 2012 would be old enough to
survive the summer without watering. However, even the 2012 crop
required extra water in the scorching-hot summer of 2015.
17. Every summer since they were planted, some trees have died,
requiring my family to buy and plant new ones. Abnormal heat due to
climate change added to these losses. Future heat waves and drought
endanger our dream of a large, thriving hazelnut orchard.
18. Another source of revenue for my family is sustainable harvest
of Douglas fir trees for lumber. Our farm is Sustainable Forestry
Initiative-certified, and we take great pride in our role as keepers of
the land. The total value of merchantable timber owned by my
grandmother on the farm is approximately $400,000.00, using
calculations based on a 2007 timber cruise conducted by Barnes and
Associates, Inc. of Roseburg, Oregon. Additionally, there are roughly
128 acres of young trees, valued currently at about $120,000.00, which
will steadily increase in value and become merchantable in the coming
decades. Wildfires, which are increasing in frequency and intensity
from the changing climatic conditions caused in substantial part by the
Federal Defendants, threaten to destroy my family's timber.
19. Increased drought and heat waves, caused in substantial part by
the Federal Defendants, make it difficult for new timber trees to grow
after cutting. For example, last year my father replanted a small
acreage of Douglas fir trees on the farm. These trees were located on a
southwest-facing slope, which exposed them to the elements and made
them especially sensitive to heat. Unusually high temperatures during
the summer of 2015 killed most of the trees. We now have to replant
this section again. While this particular planting was done by my
father at no capital cost, other plantings have typically run about
$176 per acre for trees and labor.
20. Increased fire risk and longer fire seasons make it difficult
to operate machinery on the farm in the summer months. For example, hot
temperatures limit the times of day when chainsaws can be used.
21. My family uses firewood to heat our home in the winter, and we
typically cut firewood in the summer. The Douglas Forest Protective
Association (``DFPA'') issues rules for the use of machinery outdoors
during fire season in Douglas County, where the farm is located. Due to
high summer temperatures, the DFPA frequently issued Fire Precautions
of Level II and above in 2015, prohibiting the use of chainsaws
outdoors between the hours of 1:00 p.m. and 8:00 p.m. This forced my
family to limit woodcutting to the morning and nighttime hours.
Unusually hot temperatures, caused in substantial part by the Federal
Defendants, have made it increasingly difficult to find times to cut
sufficient firewood.
22. My family has designated certain wooded areas on the farm not
to be cut, and these areas are of particular aesthetic and spiritual
significance to me. I discovered these areas as a little boy, and I
want these areas to remain intact into my old age. One protected area
is a grove of Douglas Fir trees that are nearly 80 years old. A picture
hangs in my grandmother's office of her late father, Gene Fisher,
walking through these trees in his overalls and a baseball cap. Grandpa
Gene named the area The Cathedral, perhaps because the trees look like
pillars, or perhaps because of the way the light filters through their
branches. Protected areas such as The Cathedral are threatened by the
increased drought, heat waves, and wildfire risk caused in substantial
part by the Federal Defendants.
23. The farm is home to many different species of wildlife,
including bears, mountain lions, reptiles, amphibians, and birds, which
I enjoy seeing. In particular, I enjoy visiting ponds in the spring and
summer, when they are teeming with Pacific Tree Frogs and Rough-Skinned
Newts. My family hunts deer, elk, and wild turkeys to provide food. In
the summer, I catch bass from the Umpqua River for food. Each of these
species of wildlife is adversely impacted by climate change caused in
substantial part by the Federal Defendants. Changing migration patterns
and availability of food species harms my and my family's sources of
sustenance and interest in living off of our land's bounty.
24. I enjoy fishing for steelhead and salmon on the Umpqua River
where it runs by the farm. Sea level rise, increasing water
temperature, ocean acidification, and drought, caused in substantial
part by the Federal Defendants, are harming, and will increasingly
harm, salmon and steelhead populations. In the summer of 2015, the
Oregon Department of Fish and Wildlife curtailed salmon fishing on
rivers including the Umpqua due to stress on salmon from abnormally
high water temperatures and low stream flows.
25. I enjoy swimming in the Umpqua River where it runs past the
farm. Increased summer temperatures contribute to toxic algae blooms,
which can make it unsafe to swim in the river. In 2009, four dogs were
killed by toxic blue-green algae in Elk Creek, a tributary of the
Umpqua River, about 5 miles from my home. The state issued a health
advisory for Elk Creek and adjacent sections of the Umpqua River, and I
abstained from swimming in the river for several weeks after the
incident for fear of toxic algae.
26. How Defendants Are Harming My Recreational Interests: In
addition to recreating on the farm, I also enjoy recreating at other
locations in Oregon, such as the forests surrounding the North Umpqua
River. One of my favorite places to recreate is the area around Twin
Lakes, along the North Umpqua River, where two bright-blue lakes are
surrounded by old-growth forest. I enjoy hiking, swimming, camping, and
other activities along the North Umpqua River and I have plans to
continue doing these activities each year in the immediate future. The
forests surrounding the North Umpqua River are threatened by the
increased number and severity of wildfires caused in substantial part
by the Federal Defendants.
27. In the summer of 2015, two large wildfires--the Cable Crossing
and Stouts Creek Fires--burned a combined total of over 28,000 acres in
Douglas County. Massive columns of smoke from both fires were visible
from Roseburg, and the plume from the Stouts Creek fire was visible
from my family's farm. Seeing the columns of smoke caused significant
distress for my family and me.
28. Both fires burned in areas where I had previously recreated.
Due to the Cable Crossing Fire, my friends and I were unable to camp
along the North Umpqua River on the weekend of July 30, 2015, which we
would have done but for the fires.
29. In the winter, I enjoy recreating with my friends in the snow
in the Oregon Cascades. I have many fond memories of sledding, snow
fights, and hot chocolate at Diamond Lake, including one time in eighth
grade, when two of my friends tried to bury me in the snow. Decreased
snowpack as a result of warmer temperatures caused in substantial part
by the Federal Defendants will adversely impact my enjoyment of the
forest in winter. My participation in winter sports such as skiing and
snowshoeing will be particularly affected.
30. I also enjoy recreating along the Oregon Coast. My family
occasionally goes crabbing for food, and I enjoy eating fresh seafood
at restaurants on the coast. Some of my favorite activities include
beachcombing and tide-pooling. Sea-level rise and ocean acidification,
caused in substantial part by the Federal Defendants, are increasingly
harming the delicate coastal ecosystems where I recreate.
31. When I was eleven years old, my family and I visited a beach at
Cape Arago State Park, along the Southern Oregon Coast. To my
wonderment, I found dozens of Purple Shore Crabs, each no more than 1"
or 2" in length, hiding under the rocks. There are thousands of crabs
there, all of them along just a small section of shoreline. I have
returned to that beach several times, and plan to do so again in the
immediate future. If the Federal Defendants' actions to allow and
promote unsafe levels of carbon pollution are not stopped, sea level
rise and ocean acidification will dramatically alter the narrow
ecological band in which the crabs exist.
32. Another location on the coast where I enjoy recreating with my
family is Sea Lion Caves, near Florence, Oregon. Sea Lion Caves is the
largest sea cave in the United States, and it is inhabited by dozens of
elegant Stellar Sea Lions. The sea lions are visible as they rest on
rocks inside the cave. Multi-meter sea level rise could permanently
submerge many of the rocks, making the cave inhospitable to the sea
lions. The ocean ecosystem that supports the sea lions will also be
increasingly damaged by ocean acidification and abnormally high sea
surface temperatures due to climate change. I plan to return to Sea
Lion Caves with my own children someday and hope that a healthy
population of sea lions continues to live there.
33. I enjoy hiking in Northern Washington and Glacier National
Park, where I have seen glaciers receding due to climate change. I plan
to return to Montana and Washington in the next several years, and I
also want to travel to Alaska. My recreational and aesthetic interests
are harmed as the glaciers continue to disappear before I can visit
them.
34. In the summer of 2012, I hiked to the top of Desolation Peak in
North Cascades National Park in Washington. At the top of the mountain
is a fire-spotting cabin where author Jack Kerouac served as a lookout
in 1956 and drew the inspiration for his books The Dharma Bums and
Desolation Angels. In The Dharma Bums, Kerouac describes the land
surrounding Desolation Peak as ``hundreds of miles of pure snow-covered
rocks and virgin lakes and high timber.'' I met a fire-spotter from the
National Park Service there. He told me that, if you look at a picture
from one hundred years ago, the glaciers on the surrounding mountains
are twice the size they are today. In that moment, I knew that climate
change would become a central theme of my life.
35. My Health Has Been Affected: Recent summers at home have become
increasingly smoky due to the increased severity and number of
wildfires in southern Oregon. I have asthma, which is aggravated by the
smoke. Increased pollen due to unusually warm temperatures also
aggravates my asthma and allergies. When I am suffering from asthma and
allergies, my outdoor activities are limited, which harms both my
ability to work on the farm and my ability to recreate and enjoy the
special forests and rivers surrounding my home. My asthma and allergies
will continue to worsen as climate change worsens and air quality
during the summer months continues to decline.
36. How I Am Affected By the Export Authorizations for the Jordan
Cove Project: My family's farm is only about 30 miles from the route of
the proposed Pacific Connector Natural Gas Pipeline, which would
connect to the Jordan Cove Liquefied Natural Gas Terminal at Coos Bay.
The Jordan Cove Terminal would be the largest single source of
greenhouse gas emissions in the State of Oregon after the scheduled
closure of the Boardman Coal-Fired Power Plant in 2020.
37. The potential climate impact of the Jordan Cove Energy Project
becomes much larger when one also considers upstream emissions from the
extraction and transport of the natural gas, as well as downstream
emissions from the combustion of the fuel. Natural gas is made up
primarily of methane, which is a potent greenhouse gas. This means that
significant emissions would result from methane leakage during
extraction and transport of natural gas for the Jordan Cove Project.
Additionally, according to the Pacific Connector website, the pipeline
would carry up to 1 billion cubic feet of natural gas per day. The
CO2 released from burning that much natural gas would be
equivalent to the emissions from over four million typical passenger
cars. Clearly, the construction of the Jordan Cove Energy Project would
contravene Governor Brown's stated goal to reduce Oregon's greenhouse
gas emissions.
38. The pipeline would cross 400 bodies of water in Oregon,
including two locations along the South Umpqua River where I have
visited and recreated and intend to return in the immediate future. I
have visited sections of the route in Southern Douglas County and the
intersection of the route with the famous Pacific Crest Trail. A
roughly 100-150 wide clearcut would be required for the pipeline,
causing substantial damage to these wild places that I enjoy for
recreation and aesthetic value. I would particularly love to hike the
Pacific Crest Trail again in the near future, and I hope not to see it
scarred by the pipeline project. A true and correct picture of me at
the intersection of the Pacific Crest Trail and the proposed pipeline
route is included as Exhibit 2.**
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** Editor's note: Exhibit 2 was not included in Our Children's
Trust submission for the record of the hearing.
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39. While walking along the pipeline route, I was shocked to
discover that workers on public land had already spray-painted numbers
and markers on old-growth trees to be cut, even though the pipeline has
not yet received all necessary local, state, and Federal permits. I was
particularly horrified that workers had spray-painted trees adjacent to
the Pacific Crest Trail. In my view, this defacement of trees
demonstrates the pipeline company's confidence-based on its existing
authorization from the Department of Energy to export the LNG--that it
will receive the rest of its permits, despite the project's severe
impacts on the climate and local environment.
40. One specific location on the pipeline route that I visited was
near Callahan Ridge, on Bureau of Land Management property in southern
Douglas County (Township 31s, Range 3w, the NW quarter of section 25).
A few weeks after I visited the location, the Stouts Creek Fire burned
this area of the forest. The Stouts Creek Fire directly impacted at
least a dozen miles of the pipeline route, with the proposed location
for an aboveground valve inside the fire perimeter. If constructed, the
pipeline would carry highly pressurized, explosive natural gas through
Oregon's fire-prone forests, with 17 valves located above ground. This
would further harm my interests in protecting the places where I
recreate from the increasing ravages of climate change caused in
substantial part by the Federal Defendants.
41. In an April 6, 2015 letter to the Federal Energy Regulatory
Commission (``FERC''), the U.S. Army Corps of Engineers asked that FERC
assess ``the impacts of large trees, stumps or slash catching on fire
during a forest fire event and landing over the buried pipeline and how
that could affect the ground temperature and buried pipeline integrity/
safety.'' Additionally, in a September 9, 2015 letter to FERC, Douglas
County Commissioner Chris Boice asked that FERC evaluate ``[h]ow . . .
a wild land fire [would] impact the integrity of pipeline construction
and infrastructure both before and after a wild land fire.''
42. Williams Pipeline, the company that would construct Pacific
Connector, has had four explosions at other pipelines and facilities in
the past. Leaking pipelines around the country, like the now-infamous
Sempra pipeline in Porter Ranch, California, demonstrate how common and
likely pipeline accidents are, and the risks they will pose in my
community in southern Oregon. The increased possibility of wildfires in
places I have visited, such as the area around Callahan Ridge, would
compound the risk of catastrophic accidents.
43. The Federal Defendants' disregard for the impacts of wildfires
on the pipeline mirrors the Federal Defendants' broader disregard for
the impacts of fossil fuel extraction and combustion on our climate
system. Changes to the climate system increasingly harm my way of life,
and direct environmental impacts from the construction of the Jordan
Cove Energy Project threaten to do so as well.
I certify under penalty of perjury in accordance with the laws of
the State of Oregon, and to the best of my knowledge, that the
foregoing is true and correct.
Dated this 5th day of January, 2016 at Kellogg, Oregon.
Alexander Wallace Loznak.
------------------------------------------------------------------------
------------------------------------------------------------------------
Julia A. Olson (OR Bar 062230) Joseph W. Cotchett
[email protected] [email protected]
Wild Earth Advocates Philip L. Gregory (pro hac vice)
1216 Lincoln Street [email protected]
Eugene, OR 97401 Paul N. McCloskey
Tel: (415) 786-4825 [email protected]
Cotchett, Pitre & McCarthy, LLP
Daniel M. Galpern (OR Bar 061950) San Francisco Airport Office Center
[email protected] 840 Malcolm Road
Law Offices of Daniel M. Galpern Burlingame, CA 94010
1641 Oak Street Tel: (650) 697-6000
Eugene, OR 97401 Fax: (650) 697-0577
Tel: (541) 968-7164
Attorneys for Plaintiffs
United States District Court
District Of Oregon
Eugene Division
Kelsey Cascadia Rose Juliana; Case No.: 6:15-cv-01517-TC
Xiuhtezcatl Tonatiuh M., through
his Guardian Tamara Roske- Declaration of Jaime B. In Support
Martinez; et al., of Plaintiffs' Opposition to
Plaintiffs, Defendants' Motion to Dismiss;
v.
The United States of America; Oral Argument: February 17, 2016,
Barack Obama, in his official 2:00 p.m.
capacity as President of the
United States; et al.,
Federal Defendants.
------------------------------------------------------------------------
I, Jaime Lynn Butler, hereby declare as follows:
1. I am a 15-year-old citizen of the United States and resident of
Window Rock, Arizona. I am a freshman in high school at
Colorado Rocky Mountain School in Carbondale, Colorado. My
family and I are already experiencing harm caused by
climate change and I am worried we'll experience even more
severe climate impacts in the immediate future.
2. I am a member of the Navajo Nation. My clan is Tangle People
Clan, born for the Bitter Water Clan, with my maternal
grandfathers of the Red House Clan and my paternal
grandfathers of the Towering House Clan. I am a member of
the Grand Canyon Sierra Club, which is where I first
learned about climate change. In 2011, frustrated by my
state's lack of action to combat climate change, I filed a
lawsuit against the governor of Arizona for violating her
duty to protect the atmosphere as a resource under the
public trust doctrine.
3. I grew up in Cameron, Arizona, on the Navajo Nation Reservation.
In 2011, my mom and I had to move from Cameron to Flagstaff
because of drought and water scarcity. My extended family
on the Reservation remember times when there was enough
water on the Reservation for agriculture and farm animals,
but now the springs they once depended on year-round are
drying up. My mom and I were not able to live sustainably
on the Reservation because of the costs of hauling water
into Cameron for us and our animals. I am worried that my
extended family, all of whom live on the Reservation, will
also be displaced from their land, which would erode my
culture and way of life. Participating in sacred Navajo
ceremonies on the Reservation is an important part of my
life, and climate impacts caused by the acts of Defendants
are starting to harm my ability, as well as the ability of
my family and tribe, to participate in traditional
ceremonies. Ceremonies are governed by phases of the moon
and seasons. The dry climate and extreme winds have spread
the invasive plant species (Camel Thorn) and they have
replaced grasslands, river banks are in accessible due to
Tamarack, water wells need to be replaced with deeper wells
etc. All of this affects our ability to offer livestock,
food and water for ceremonies. Ceremonies often require
objects secured in nature that were once plentiful IE.
medicinal plants, hides, and feathers etc. Now they are
not, scarcity means they cost more or are no longer
available.
4. Once we moved off the reservation, we moved to the outskirts of
Flagstaff, along the Kaibab National Forest. The forest
there, was my favorite place to spend time. I find peace
being outside in the forest surrounding my home, and when I
was home I spent hours each day walking in the forest.
5. Large parts of the Kaibab National Forest have been destroyed due
to pine beetle infestations and forest fires, both of which
are caused by, or exacerbated by, fossil fuel emissions
authorized by the Federal Defendants. The emissions cause
warmer temperatures, which lower the resistance of the
trees to the infestations. The hotter temperatures,
drought, and pest infestations dry the forest, making it
more susceptible to wildfires. I have seen the beetles and
they are huge and ugly.
6. In 2014, my mom and I were evacuated from our home for 2 days
because of the Oak Creek Canyon fire north of our home.
Winds brought smoke and ash into our neighborhood. I'm
worried that the area surrounding my home is becoming
unsafe due to an increase in drought conditions and forest
fires caused by the acts of Defendants in permitting,
subsidizing, and otherwise allowing unrestrained fossil
fuel emissions.
7. As a result of the pine beetle infestations and forest fires
caused by the acts of Defendants, my ability to spend time
in the Kaibab National Forest has been limited and will be
limited in the immediate future.
8. I have been negatively affected by the increasing temperatures,
which limits the time I'm able to safely spend time
outdoors. Hotter temperatures and drought also negatively
impact the vegetables we grow for food on our property in
Flagstaff. Our water bills go up to irrigate our little
garden, but the worst problem is how quickly the garden
dries up if we are away for an extended time. Also the
forest animals (raccoons, coyotes and rabbits) come into
our yard, over the fencing to access our water or garden.
On the reservation we simply stopped farming. Although we
had dryland farmed using drought resistant corn, relying on
winter snow, the dry topsoil was too deep to find damp
earth over 12 inches in most places. Nothing would grow, so
we stopped our efforts. Fewer and fewer people farm,
especially dryland farming.
9. My severe allergies have become increasingly worse over the last
several years. I take over-the-counter medication to combat
my symptoms. In the forest it is spring and summer pollens,
in the desert on the reservation, it is the dust and
sandstorms that make life very hard. I find my family gets
sore throats during windy times, especially summer, as the
dust affects our breathing.
10. With record-setting temperatures and a drought that has lasted
several years, I fear for my future and for the future of
my family, our history, our traditions, and our way of
life.
I certify under penalty of perjury in accordance with the laws of
the State of Arizona, and to the best of my knowledge, that the
foregoing is true and correct.
Dated this 5 day of January, 2016 at Flagstaff, Arizona.
Jaime Lynn Butler.
Exhibit C: Expert Report of Dr. G. Philip Robertson
------------------------------------------------------------------------
------------------------------------------------------------------------
Expert Report of
G. Philip Robertson
University Distinguished Professor of Ecosystem Ecology
Michigan State University
------------------------------------------------------------------------
Kelsey Cascadia Rose Juliana; Xiuhtezcatl Tonatiuh M., through his
Guardian Tamara Roske-Martinez; et al.,
Plaintiffs,
v.
The United States of America; Donald Trump, in his official capacity as
President of the United States; et al.,
Defendants.
In the United States District Court
District Of Oregon
(Case No.: 6:15-cv-01517-TC)
Prepared for Plaintiffs and Attorneys for Plaintiffs:
------------------------------------------------------------------------
Julia A. Olson Philip L. Gregory
[email protected] [email protected]
Wild Earth Advocates Gregory Law Group
1216 Lincoln Street 1250 Godetia Drive
Eugene, OR 97401 Redwood City, CA 94062
Tel: (415) 786-4825 Tel: (650) 278-2957
------------------------------------------------------------------------
Table of Contents
Table of Acronyms, Abbreviations, and Definitions
Introduction
Executive Summary
Expert Opinion
1.0 Introduction
2.0 Scale of the Problem
3.0 Soil Carbon Cycling and Storage
3.1 Measuring Soil Carbon Storage
3.2 Soil Carbon Gain by Improved Land Management
3.2.1 Cropland Management
3.2.2 Cropland Conversion to Perennial Grasses
3.2.3 Grazing Lands Management
3.2.4 Frontier Technologies
3.2.5 Wetlands Restoration
3.2.6 Forest Management
4.0 Agricultural Greenhouse Gas Abatement by Land Management
4.1 Measuring Nitrous Oxide and Methane Fluxes
4.2 Avoided Emissions by Improved Land Management
4.2.1 Reduced Nitrous Oxide Emissions from
Field Crops
4.2.2 Rice Water Management for Methane
4.2.3 Cellulosic Bioenergy Production on
Grain Ethanol Lands
4.2.4 Cellulosic Bioenergy Production on
Marginal Lands
5.0 Total Mitigation Potentials
5.1 Global Estimates of Potentials for Soil Carbon Gain
5.2 U.S. Potentials for Negative and Avoided Emissions by
Land Management Change
5.3 Barriers that Prevent Optimized Biotic Greenhouse Gas
Mitigation in the U.S.
6.0 Concluding Opinions
Table Of Acronyms, Abbreviations, and Definitions
BECCS: bioenergy with carbon capture and storage
C: carbon
Ceq: carbon equivalent; used to quantitatively compare
greenhouse gases via a common metric based on global
warming potentials for individual gases
CO2: carbon dioxide; contains 27.3% carbon
CO2eq: carbon dioxide equivalent
EPA: U.S. Environmental Protection Agency
DOE: U.S. Department of Energy
GtC: gigatonne of carbon, equivalent to 1 billion tonnes of
carbon, or 1 PgC; 1 GtC = 1,000 MtC
ha: hectare, equivalent to 2.47 acres
IPCC: United Nations Intergovernmental Panel on Climate Change
Mha: million hectares, 1 Mha is equivalent to 2.47 million
acres
MtC: million tonnes of carbon, sometimes abbreviated MMTC;
1,000 MtC = 1 GtC
N2O: nitrous oxide
NRCS: Natural Resources Conservation Service
PgC: petagram of carbon, equivalent to 1015 gC
ppm: parts per million
tC: tonne of carbon, equivalent to 1,000 kgC or 106 gC
USDA: U.S. Department of Agriculture
Avoided Emissions: Greenhouse gas emissions not yet released that
could be avoided if practices were altered from conventional practices.
This includes fossil fuel emissions that are avoided by substituting
biofuel combustion for fossil fuel combustion.
Carbon Sequestration: Any process that removes carbon dioxide from
the atmosphere and stores the carbon portion in natural sinks like
soils.
Negative Emissions: Greenhouse gas (CO2eq) removed from
the atmosphere with the carbon portion sequestered for long periods of
time--sometimes indefinitely--within natural carbon sinks like soils
and forests. In this report, negative emissions are those above and
beyond the existing rate of natural sinks.
Federal Land: All U.S. federally-owned or federally-managed lands
including forest lands, range lands, other agricultural lands,
wetlands, and waterways.
Lands of the United States: All lands, both publicly owned and
privately owned, within the boundaries of the United States.
Conterminous lands of the United States: All lands, both publicly
and privately owned, within the 48 adjoining states plus the District
of Columbia; also known as the contiguous U.S.
U.S. Forests: All forestlands within the United States Federal
Forestland: All U.S. federally-owned or federally-managed forestlands.
Introduction
I, G. Philip Robertson, have been retained by the Plaintiffs in the
above-captioned matter to provide expert testimony about the potential
capacity for improved management of United States forest, range and
agricultural lands to achieve net negative carbon emissions and avoid
future greenhouse gas emissions. In this report I provide background on
the global carbon cycle, describe how different land management
practices can contribute to negative and avoided emissions, and provide
a quantitative assessment of the potential for changes in management
practices to provide meaningful greenhouse gas mitigation.
I have worked in the field of carbon and nitrogen biogeochemistry
for 40 years since beginning my Ph.D. studies in 1976. I am currently
University Distinguished Professor of Ecosystem Ecology in the
Department of Plant, Soil and Microbial Sciences at Michigan State
University, where I have held a regular faculty position since 1987. I
have been a University Distinguished Professor for the last 7 years.
Since 2017 I have also held the title of Scientific Director for the
Department of Energy's Great Lakes Bioenergy Research Center at the
University of Wisconsin and Michigan State University. For my entire
career the main focus of my research has been studying the processes
that regulate biogeochemical cycles of carbon and nitrogen at multiple
scales, including plant, soil, and microbial interactions that affect
the delivery of important ecosystem services such as climate stability,
water quality, and plant productivity. I work primarily in agricultural
ecosystems, and more broadly on the issue of agricultural
sustainability, which includes the responses of cropping systems to
climate change and the potential for land management to contribute to
greenhouse gas mitigation. My CV, which includes a statement of my
qualifications, is contained in Exhibit A * to this expert report. A
list of publications I authored within the last 10 years is attached as
Exhibit B * to this expert report.
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* Editor's note: the Our Children's Trust submission for the record
for this hearing does not include Exhibits A-C. It has been reproduced,
as submitted, herein. The full report is retained in Committee file and
is available at: http://blogs2.law.columbia.edu/climate-change-
litigation/wp-content/uploads/sites/16/case-documents/2018/
20180628_docket-615-cv-1517_exhibit-11.pdf.
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In preparing my expert report and testifying at trial, I am not
receiving any compensation and am providing my expertise pro bono to
the Plaintiffs given the financial circumstances of these young
Plaintiffs. I have not provided previous testimony within the preceding
4 years as an expert at trial or by deposition. My report contains
citations to all documents that I have used or considered in forming my
opinions, listed in Exhibit C * to this report.
The opinions expressed in this report are my own, not necessarily
the opinions of any of the institutions for which I work or donate my
time. The opinions expressed herein are based on the data and facts
available to me at the time of writing, as well as based upon my own
professional experience and expertise. All opinions expressed herein
are to a reasonable degree of scientific certainty, unless otherwise
specifically stated. Should additional relevant or pertinent
information become available, I reserve the right to supplement the
discussion and findings in this expert report in this action.
Executive Summary
Earth's carbon is found in six reservoirs: rocks, oceans,
atmosphere, plants, soil, and fossil deposits. In the carbon cycle,
carbon moves from one reservoir to another. The human-induced transfer
of carbon from fossil deposits to the atmosphere is causing Earth to
warm. Even when that transfer ceases, in order to return the
atmospheric reservoir to a point conducive to human well-being, we will
need to remove carbon from the atmosphere and store it in other
reservoirs. This is known as carbon sequestration or negative
emissions. The potential for increased carbon sequestration from U.S.
forest, range, and agricultural land management is, at peak, around
0.414 GtCeq per year (414 MtCeq per year). This
could result in negative emissions within the U.S. totaling about 21
GtCeq by 2100. Changes to land management practices could
avoid the emissions of another 0.12 GtCeq per year, totaling
9.7 GtCeq by 2100. All told, over the period 2020 to 2100,
changes to land management practices in the U.S. could mitigate more
than 30 GtCeq between 2020 and 2100, which is over 30% of
the negative and avoided emissions needed, after phasedown of fossil
fuel emissions, to return Earth's atmosphere to a more stable state.
Three types of CO2 removal are most widely discussed
today: (1) Improved land management, (2) Bioenergy with CO2
capture and storage (referred to as BECCS), and (3) Direct air capture.
BECCS and direct air capture are both theoretically possible but
currently unproven at any meaningful scale, and thus are not analyzed
in this report. Of these three, improved land management represents the
most mature, technically feasible, widely deployable, and lowest cost
option currently available. Thus, this report focuses on improving land
management to remove and store CO2 and to reduce future
emissions of three key greenhouse gases--CO2, nitrous oxide,
and methane.
Soil represents one of the largest actively cycling reservoirs of
carbon on earth, most of which is stored in the form of soil organic
matter, largely comprised of decomposing plant residue. Almost
everywhere, conversion of native forest and grasslands to agriculture
has resulted in a 30-50% loss of this carbon to the atmosphere as
further decomposition to CO2 is accelerated. Almost all
soils actively managed for agriculture, as well those that have been
abandoned from agriculture due to degraded fertility, have soil carbon
levels well below their original levels, providing significant
opportunities to sequester additional carbon.
There are a number of well-tested methods to increase soil carbon
through agricultural practices on land used to grow annual crops.
Avoiding tillage with no-till technology is one well-recognized
practice to rebuild soil carbon. Other practices can be just as
effective: adding winter cover crops to avoid bare soil for most of the
year can increase soil carbon, as can diversifying crop rotations--
growing more than one or two crops in sequence--and applying compost or
manure. Growing perennial grasses or trees on degraded or low value
agricultural soils can also result in significant carbon gains. On
pastures and rangeland, soil carbon storage can be improved by
increasing plant productivity via improved plant species and by
avoiding over grazing via careful attention to the number of livestock
per acre. About 43% of all pasture and rangeland in the U.S. is managed
by Federal agencies.
Forests can also be managed to enhance carbon sequestration in
trees and soil. Faster growing species accumulate more carbon over
their lifetimes and therefore planting more of these species will store
more carbon in wood, as will growing trees in longer rotations (the
number of years between harvests). A number of management factors can
increase forest soil carbon. About 42% of all forestland in the
conterminous U.S. is managed by Federal agencies.
In addition to increasing carbon sequestration, changes in land
management practices on Federal and private lands can also reduce the
amount of greenhouse gas emissions stemming from land use. Nitrous
oxide is a greenhouse gas 250-300 times more potent than
CO2. Agriculture is responsible for 84% of global
anthropogenic nitrous oxide emissions, and most agricultural emissions
(62%) come from soils amended with nitrogen from fertilizers, manures,
or legumes. Reducing nitrogen fertilizer rates to those needed for
optimum yields is the most reliable means to reduce nitrous oxide
emissions from fertilized cropping systems.
Methane is 28-36 times more potent than CO2.
Agricultural methane emissions come from digestive fermentation by
livestock (52%), rice cultivation (22%), biomass burning (19%), and
livestock manure handling (8%). Rice cultivation practices and
livestock management offer important land-use related methane
mitigation opportunities. Methane from rice production can be minimized
through periodic drainage of flooded rice fields.
Finally, there is an opportunity to reduce greenhouse gas emissions
and increase carbon sequestration by growing cellulosic bioenergy crops
such as switchgrass on marginal lands that were formerly in agriculture
and on lands now used to grow corn for grain ethanol.
All told, technology is available today to store carbon or avoid
future greenhouse gas emissions from agriculture in the U.S. equivalent
to more than 30 GtCeq by 2100. Farmers, ranchers, and
landowners have shown a willingness to accept payments for implementing
such practices. Financial incentives and Federal policies will need to
be aligned with the sequestration practices described below in order to
achieve this scale of increased sequestration.
Expert Opinion
1.0 Introduction
Carbon is one of the most abundant elements on Earth. Most of the
carbon on Earth is stored in rocks. The rest of Earth's carbon is in
our oceans, atmosphere, plants, soil, and fossil fuels. Earth's carbon
cycle involves the flow of carbon between each of these carbon
reservoirs (or sinks). Some of the flow is very slow and some is fast.
When carbon moves out of one reservoir it enters another, as depicted
in Figure 1.
Figure 1
This diagram of the fast carbon cycle shows the movement of
carbon between land, atmosphere, and oceans. Yellow numbers are
natural fluxes, and red are human contributions in gigatonnes
of carbon (GtC) per year. White numbers indicate stored carbon
(carbon locked in deep geological reservoirs is not included
except for fossil fuel reserves that could be mined). The human
contribution, though seemingly small, adds up to a large
imbalance and consequent increase in atmospheric
CO2. (https://earthobservatory.nasa.gov/Features/
CarbonCycle/)
The atmosphere's CO2 content is largely determined by
the balance between processes that remove CO2 from the
atmosphere, such as photosynthesis and CO2 absorption by
seawater, and processes that return CO2 to the atmosphere,
such as respiration and fossil fuel burning. About 50% of the
CO2 that humans add to the atmosphere each year by burning
fossil fuels is removed annually by natural removal and storage
processes; the remainder accumulates in the atmosphere.
CO2 transferred from the fossil deposits reservoir to
the atmosphere through the burning of fossil fuels results in rising
temperatures on Earth, as predicted by theory in the 19th century. In
order to restore the Earth's energy balance so that temperatures can
stabilize at safe levels for humanity and our natural systems, the
carbon content of the atmosphere must be reduced. Such reductions will
happen naturally over millennia if carbon emissions from the fossil
reservoir cease. However, to avoid unsafe temperature increases,
CO2 must be removed more quickly. Managing plant and soil
reservoirs for greater carbon storage represents a way to reduce--or
mitigate--atmospheric CO2. Increasing the amount of carbon
stored in these reservoirs is commonly referred to as carbon
sequestration, carbon storage and removal, or negative emissions.
Decreasing the amount of carbon stored in the atmosphere is widely
acknowledged to require removing and storing CO2 in other
carbon reservoirs (negative emissions) as well as curtailing
CO2 sources such as fossil fuel burning (decarbonization)
and deforestation. Of almost 900 mitigation scenarios evaluated by the
Intergovernmental Panel on Climate Change (IPCC) with integrated
assessment models,\1\ all of the 116 deemed effective involved
curtailing sources of CO2 and more than 100 also involved
CO2 removal.2, 3 Both CO2 source
reduction and CO2 removal are thus central to future climate
mitigation efforts. Indeed, under any climate recovery scenario,
negative CO2 emissions (removal and storage) will be
required starting immediately to bring atmospheric CO2
concentrations back within safe limits for our biological and human
systems.4, 5
Three types of CO2 removal are most widely discussed
today: (1) Improved land management, (2) Bioenergy with CO2
capture and storage (referred to as BECCS), and (3) Direct air
capture.3, 6, 7 Improved land management entails managing
ecosystems to sequester more carbon in living biomass such as long-
lived trees and in dead biomass such as organic matter in soils and
ocean sediments. Bioenergy with CO2 capture and storage
refers to extracting energy by burning biomass and storing the
resulting CO2 in geologic reservoirs. Direct carbon capture
involves extracting CO2 directly from the air via enhanced
weathering of rocks and minerals or direct air capture, with subsequent
geologic storage. BECCS and direct air capture are both theoretically
possible but currently unproven at any meaningful scale, and thus are
not further analyzed in this report. Enhanced rock weathering and ocean
fertilization have also been proposed but are less widely discussed or
tested.7, 8 Of this group, improved land management
represents the most mature, technically feasible, widely deployable,
and lowest cost option currently available.3, 7 We have
known about this option and its environmental co-benefits for decades.
In addition to managing land for negative emissions, land
management can also contribute to climate mitigation by avoiding
further greenhouse gas emissions.4, 9 This can be done, for
example, by reducing deforestation, a practice responsible for 10% of
total global carbon emissions today,\10\ almost all outside the U.S.
But greenhouse gases are also emitted by other land management and
agricultural practices. For example, nitrogen fertilizer emits
CO2 when manufactured and emits nitrous oxide when applied
to soils. Methane is emitted by soils under rice cultivation. Land
management practices that avoid or reduce greenhouse gas emissions thus
represent an additional climate mitigation opportunity. Some management
changes have the potential to both curtail CO2 emissions and
remove CO2 from the atmosphere. For example, producing
ethanol from perennial grasses instead of corn grain both consumes less
fossil fuel (curtailing CO2 emissions) and stores more soil
carbon (enhancing CO2 removal and storage).
In the pages that follow are current opportunities for improved
land management practices in the U.S. that are feasible and currently
available to mitigate climate change. I emphasize those land management
practices most likely to produce significant negative emissions--those
that remove and store CO2 from the atmosphere--and as well
those practices capable of reducing emissions of CO2 and the
other biogenic greenhouse gases nitrous oxide and methane, respectively
responsible for 82%, 10% and 5% of total U.S. greenhouse gas
emissions.\11\
2.0 Scale of the Problem
From pre-industrial times fossil fuels have added 327 GtC to the
atmosphere (half of that just since the 1980s),\12\ with another 156
GtC added by deforestation. In 2014 fossil fuel burning added 8.8 GtC
to the atmosphere,\13\ with the U.S. responsible for 1.5 GtC \11\ or
about 17% of the global total that year. In recent years global
deforestation has added annually another 0.9 GtC,\10\ none from the
U.S.\11\
To avoid or deflect the most disruptive effects of climate change
now underway--sea level rise, shifting climate zones, species
extinctions, coral reef decline, climate extremes, expanded forest
burning, and human health impacts--requires returning atmospheric
CO2 concentrations, currently above 400 parts per mission,
to 350 parts per million or below.5, 14 This CO2
level would largely restore Earth's energy balance, keeping
temperatures within the Holocene range to which human societies,
agriculture, and other species are adapted. This could be achieved by
limiting total cumulative fossil fuel emissions to 500 GtC coupled with
cumulative negative emissions equivalent to 100 GtC by 2100.\4\ Hansen,
et al.,\4\ identify two major ways that land management can achieve a
100 GtC drawdown this century: (1) negative emissions from forest and
soil carbon storage including reforestation and improved agricultural
practices, and (2) avoided emissions from ending deforestation and
deriving bioenergy from dedicated energy crops that do not compete with
food crops. I agree these strategies have the potential to produce that
quantity of negative emissions and both are discussed in more detail,
below.
Ocean and land sinks today remove from the atmosphere about half of
the CO2 emitted by anthropogenic activities, or 4.9 GtC
annually for the 1990-2000 period.\10\ About \1/3\ of the emitted
CO2, 2.6 GtC for this period, is removed by land sinks.\10\
In the U.S., land sinks remove annually 0.2 GtC.11 Negative emissions
as discussed here are in addition to these existing natural sinks.
3.0 Soil Carbon Cycling and Storage
Carbon accumulates naturally during soil development as plants
colonize new substrates such as sand and rock surfaces, transform
atmospheric CO2 to new biomass via photosynthesis, and then
leave behind carbon-rich leaves, wood, roots, and other biomass that
then decompose. Some plant parts decompose quickly, others more slowly.
Wood, for example, is very resistant to microbial attack, and some of
the natural carbon products that are highly resistant to microbes can
persist for thousands of years. Soil organic carbon can also be trapped
within soil aggregates, which are hardened clusters of soil particles
(grains of sand, silt, and clay) wherein very low oxygen levels inhibit
microbial activity. And some decomposition products, usually in the
form of complex organic molecules, can be highly resistant to decay
especially when bound to soil mineral surfaces.
Over time, most soils accumulate organic carbon to some equilibrium
value that represents a few percent of total soil mass; in most soils
this value is less than 5%. In waterlogged or cold soils such as those
under bogs and tundra, decomposition occurs very slowly-microbial
activity is suppressed by low oxygen or low temperatures or both--and
in these locations, carbon can accumulate to very high proportions of
soil mass.
Soil thus contains organic carbon of different ages and different
susceptibilities to microbial decomposition. Soil disturbance--both
natural and anthropogenic--can stimulate decomposition by altering the
soil physiochemical environment. Clearing land for agriculture does
exactly this: plowing the soil breaks apart aggregates and exposes
protected carbon to microbial attack, and allowing soil to remain bare
for much of the year causes it to be wetter and warmer--perfect
conditions for microbes to convert soil organic carbon back to
CO2 in their quest for energy. Almost everywhere, conversion
of native forest and grassland soils to agriculture results in a 30-50%
loss of carbon from the top soil layers within just a decade or 2
(Figure 2),\15\ a general pattern well-recognized since the 19th
century.\16\ Global estimates of this loss total 133 GtC, split nearly
evenly between crop and grazing lands.\17\
Figure 2
Changes in soil organic matter fractions following
cultivation of a soil profile undernative vegetation. Redrawn
from Grandy and Robertson (2006).\26\
The basis for soil carbon gain is thus the net balance between
photosynthesis, which fixes CO2 into biomass carbon, and
decomposition, which transforms biomass carbon back to CO2.
Thus the organic carbon content of soils is regulated by the balance
between the rate of carbon added to soils from plant residues (both
aboveground biomass and roots), plus, in agricultural soils, organic
amendments such as compost and manure, and the rate of carbon lost from
soil, mainly via decomposition, though soil erosion can be locally
important.
3.1 Measuring Soil Carbon Storage
The total amount of organic carbon in a soil sample can be measured
by a variety of techniques, most reliably by thermal oxidation.\18\
Historically, carbon has been assessed by combusting a small soil
sample at temperatures sufficient to convert organic carbon to
CO2. This generally entails placing a soil sample of known
weight into a high-temperature furnace for several hours; the
difference in mass on re-weighing represents oxidized carbon and by
difference, the carbon content of the soil prior to combustion. A
variation on this technique uses a chemical oxidizing agent rather than
direct heat to combust the carbon. Today soil carbon is most commonly
analyzed by gas chromatography: an automated sampler drops a tiny
amount of ground, well-mixed soil into an oxygen-infused chamber that
is subsequently ignited; the CO2 liberated is then measured
by gas chromatography or infrared gas absorption analysis.\19\ Data
from samples so analyzed can be used with high confidence; identical
samples typically vary no more than 5-10%.
Due to the natural variability of soil at even small scales, most
field experiments to document the effects of a management practice on
soil carbon typically compare practices for similar slope positions,
and often in replicated small plots, in order to detect differences
with statistical confidence. Even so, to dependably detect soil carbon
change typically requires a decade or more \20\ because change occurs
slowly such that it is much easier to detect with confidence a 10%
carbon change over 10 years that a 1% change over 1 year. Thus, both
long-term sampling and experiments are important for assessing changes
in soil carbon.
Soil carbon also varies with depth in the soil profile, so it is
also necessary to design sampling programs to directly compare similar
depths. Typically, the upper few cm of soil contain the most carbon,
with concentrations falling rapidly in lower layers. Lower subsoil
carbon concentrations plus its greater natural variability make it
especially difficult to detect soil carbon change in lower
horizons.\21\ Thus, most of what we know about the effects of land
management practices on soil carbon stores comes from changes in
surface horizons,\22\ typically the upper 25-30 cm where most root
growth and biological activity occurs.
3.2 Soil Carbon Gain by Improved Land Management
Soils globally contain 1,800 GtC to 1 m depth, comprising the
largest terrestrial organic carbon pool and representing about twice
the amount of carbon that is in the atmosphere (830 GtC). Soils of the
conterminous U.S. contain 81 GtC to 1 m depth.\23\ Thus a relatively
small percentage increase in soil carbon represents a potentially
strong climate change mitigation opportunity.\24\
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This includes soils on both Federal and private lands in the
lower 48 United States.
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Soil carbon stocks can be increased by increasing the rate of
carbon additions to soil or by decreasing the rate of decomposition, or
both. Croplands and grazing lands can be managed for enhanced carbon
gain, but for each there are limits to the extent of gains possible.
First, with changes to soil management that lead to carbon gain, soil
carbon stocks tend towards a new equilibrium asymptotically, such that
gains diminish as the new equilibrium level is approached, usually over
a few decades (Figure 2).\25\ Second, this equilibrium level is finite
for a given soil at a given location: soils tend to have a saturation
level above which no further soil carbon increase is likely
possible.\26\ Furthermore, if this equilibrium is reached because of
high exogenous inputs such as compost or manure, cessation of these
inputs will lead to a new, lower equilibrium.\27\
Nevertheless, almost all soils in the U.S. actively managed for
agriculture, as well as those that have been abandoned from agriculture
due to degraded fertility, have soil carbon levels well below
saturation, providing significant opportunities to manage for
additional carbon. Cropland surface soils of the central U.S. are
believed to have lost 50% of their pre-cultivation carbon stocks by
1950.\28\
A number of agricultural practices have the potential to increase
soil carbon. In most cases these practices differ by management system:
practices for croplands are different from practices for grazing lands
and both are different from practices for managed forests.
Nevertheless, the principles in all cases are the same, and some
practices can be applied across systems. Practices below are grouped
into three categories: those relevant to cropland and grazing lands
management, wetlands restoration, and forest management.
In Section 5, below, the total potential impact for the U.S. (GtC)
is estimated based on the average likely carbon gain (GtC
ha-1 yr-1) for a given practice multiplied by the
areal extent (acreage) on which the practice could be implemented, and
then again by the number of years between 2020 and 2100 that the
average gain might persist. In some cases, multiple practices could be
implemented on the same lands--many cropland management practices, for
example, such as no till adoption and diversified crop rotations. In
other cases, practices are mutually exclusive--cropland management
practices, for example, cannot be applied to set-aside cropland
converted to perennial grasses. And some practices are already
implemented to limited degrees.
Areal extents of potential practices are thus additional to any
existing implementation, and are intentionally conservative in order to
avoid the likelihood of double counting. The maximum extents possible
are, of course, constrained by available land area; all private and
public lands within the conterminous U.S. (the lower 48 states), on
which Section 5 estimates are based, contains 159 Mha of cropland, 265
Mha of rangeland and pasture, and 256 Mha of forest lands.\29\
About 43% of total rangeland and pasture30 and 42% of total forest
land \31\ in the conterminous U.S. are owned by the Federal Government
and thus practices could be implemented directly. On privately held
lands practices can be encouraged through financial incentives such as
tax abatements or direct payments, used since the 1930s to advance
national conservation goals. In 2017, for example,\32\ the USDA spent
$2.0 billion for the Conservation Reserve program, which kept 9.4 Mha
of environmentally sensitive land set aside from production, including
0.8 Mha of restored wetlands; $2.8 billion for the Environmental
Quality Incentives Program and the Conservation Stewardship Program,
which provide landowners conservation assistance to reduce soil erosion
and enhance water, air, and wildlife resources on crop and grazing
lands; and $0.5 billion for the Agricultural Conservation Easement
Program, which helps to conserve grazing and wetlands in particular.
Other than fire suppression, minor assistance was provided to private
forest landowners, chiefly through the $0.02 billion Forest Stewardship
program.
The duration of a given practice's carbon gain is likewise
constrained by the average amount of time it takes the sink, whether
soil or trees, to reach local equilibrium. For soils this will vary
mainly by climate, management, and initial carbon content--for example,
a degraded or long-cultivated soil will take longer to equilibrate than
will a soil closer to its original carbon content. For trees this will
vary mainly by location, species, and soil fertility--for example,
trees in the Rocky Mountains grow more slowly than trees in the Pacific
Northwest, and red pine grows faster than Douglas fir. On the other
hand, the duration of avoided emissions is not constrained by biology--
the emissions reductions will persist for as long as the practice
persists.
3.2.1 Cropland Management
Cropland Management: Tillage
Farmers plow to control weeds, manage residues, and prepare the
seed bed for planting. Plowing also causes carbon loss by mixing plant
residues throughout the surface soil, bringing it into contact with
microbes and other soil organisms like earthworms, and with moister
soil more favorable to microbial activity. Plowing also breaks apart
soil aggregates, especially the larger ones, exposing trapped organic
carbon to aerobic microbes that readily respire it to
CO2.\33\ In fact much of the early increase in atmospheric
CO2 starting in the 19th century was the result of pioneer
cultivation,\34\ which stimulated microbial activity and the conversion
of soil organic matter to CO2.
Modern advances in tillage technology provide many more options
than traditional moldboard plowing, which inverts the upper 20-30 cm of
soil. Contemporary lower-impact options, typically termed conservation
tillage, range from chisel plowing, which avoids inverting the soil
profile, to no till, which leaves the soil profile completely
undisturbed. With no till, weeds are usually suppressed with herbicides
or, at smaller scales, with cover crops and mechanical crimping, and
seeds are planted with equipment that places seeds in slits cut through
the preceding crop's residue, which is left to decompose on the soil
surface rather than buried. Both of these practices can significantly
increase the amount of carbon stored in the soil.
The primary impetus for the development of no-till and other
conservation tillage techniques was erosion control.\35\ Under no-till
corn, for example, erosion can be reduced as much as 90%
36-39 by reducing the exposure of soil aggregates to
raindrop impacts and to freeze-thaw and wet-dry cycles, allowing more
to remain intact, protecting entrapped carbon from microbial oxidation
to CO2.\40\ And plant residue, by remaining on the soil
surface, decomposes more slowly.\41\
Carbon accumulation due to no-till has been documented in soils
worldwide, including the U.S. since the 1950s.\35\ Long-term field
experiments comparing no-till to conventional tillage show typical no-
till increases of 0.1-0.7 tC ha-1
yr-1.42, 43 West and Marland \44\ estimated
average rates of 0.3 tC ha-1 yr-1, a rate
consistent with other syntheses 45-48 including Eagle, et
al.'s,\48\ who included the impact of nitrous oxide emissions in their
overall estimate. Where soil carbon is already high, no-till has less
capacity to increase soil carbon; no till also has less capacity to
increase soil carbon in cooler or wetter areas where it can sometimes
reduce crop yield.\49\ Other forms of conservation tillage can also
build soil carbon but at lower rates and less consistently.\50\
Importantly, to achieve a long-term increase in soil carbon from
no-till practices, the no-till practices must be implemented
continuously. Stored soil carbon can be quickly oxidized to
CO2 when no-till soils are tilled,15, 51 with
much of the no-till carbon benefit lost after a single tillage
event.\52\ Thus, while no-till is practiced on as much as 36% of U.S.
soils annually, because it is practiced at least 3 years in a row on
less than 13% of U.S. cropland,\53\ and almost certainly less on a
permanent basis, there presently is little long-term climate benefit.
Efforts to use no-till as a negative CO2 emissions strategy
must consider no-till longevity an important design component.
An exception to this continuous long-term no-till rule is the
potential for burying surface soil carbon with a single inversion
tillage. In humid climates with poorly drained soils, a one-time deep
inversion tillage may promote soil carbon storage by moving high-carbon
surface soils to >50 cm depth, where decomposition is slowed due to
cooler, wetter conditions with less oxygen. At the same time, low
carbon soil at depth is moved to the surface where it can accumulate
more carbon. In one of the only long-term deep tillage experiments,
Alcantara, et al.,\54\ found carbon accumulation rates equivalent to 1
tC ha-1 yr-1 in Germany.
A further consideration is the potential for soil carbon to change
at depths below the top soil horizon. Almost all quantitative
assessments of no-till to date have assessed changes in soil carbon in
the upper 25-30 cm of the soil where roots, soil organic matter, and
microbes are most concentrated. However soil carbon also occurs at
lower depths,\17\ and there is the potential,22, 55 but
little quantitative evidence,21, 56 for soil carbon changes
at depth to counteract surface soil gains in some locations.
Although carbon savings associated with no-till also accrue from
reduced fuel use due to fuel saved by not plowing, this saving is
typically small (typically <0.05 tC ha-1
yr-1),44, 57 though permanent in that it is not
subject to re-release like stored soil carbon.
Cropland Management: Summer Fallow and Winter Cover Crops
In most annual cropping systems soils are left bare for a
substantial portion of the year. Without plants, soils lose carbon
because there are fewer carbon inputs from roots and aboveground
residues and because decomposition rates are higher--soils are wetter
and warmer without plant transpiration and shading.\58\ For most annual
crops in the U.S. (e.g., corn, soybean, cotton, sorghum, peanut, and
vegetables) the fallow period occurs over winter, stretching from mid-
fall to late-spring (5-7 months). For fall-planted crops like winter
wheat and winter canola, the fallow period occurs over summer and lasts
from the mid-summer harvest to at least late fall ( 3 months), or,
where followed by a summer crop, to the following spring (9-10 months).
Thus for most U.S. cropland the soil is bare for much of the year. In
semi-arid regions summer fallows are often used to conserve soil
moisture for a following crop.
Eliminating summer fallow periods can, in the U.S., sequester up to
0.3 tC ha-1 yr-1 of soil carbon depending on
climate and tillage method. Eagle, et al.,\48\ estimated an average
soil carbon gain of 0.16 tC ha-1 yr-1. Less the
CO2 cost of the additional nitrogen fertilizer used reduces
the net benefit to 0.09 tC ha-1 yr-1. Where
summer fallow is used for water conservation, summer fallow cannot
likely be eliminated but could be used less frequently, such as every
third or fourth year instead of every second or third
year.59, 60
Winter cover crops include annual grasses such as rye and legumes
such as clover that are typically planted in the fall following harvest
of the preceding crop. Prior to winter the cover crop germinates and
grows to a size that allows it to survive wintertime temperatures in a
dormant state, after which it grows rapidly the following spring.
Before planting the following summer crop, the cover crop is killed and
then either left to decompose on the soil surface or, more commonly but
not necessarily, buried with tillage. Adding winter cover crops to a
rotation can add 0.03-0.55 tC ha-1 yr-1 of soil
carbon,61, 62 depending on climate, even when the cover crop
is tilled under--providing in many cases a carbon gain equal to no-
till.\63\
Winter cover crops provide the additional co-benefit of reducing
the need for nitrogen fertilizer due to their ability to scavenge the
previous crop's leftover soil nitrogen that would otherwise be leached
to groundwater or emitted to the atmosphere, and, in the case of legume
cover crops, the ability to capture or ``fix'' nitrogen from air. This
captured or new nitrogen is then made available to the next crop,
reducing the need to apply fossil fuel-derived nitrogen fertilizers,
thereby creating additional carbon savings by avoiding one of the most
significant sources of greenhouse gases in intensively managed field
crops.\64\
A recent meta-analysis \65\ estimates average carbon sequestration
potentials for winter cover crops of 0.32 tC ha-1
yr-1 globally, with a number of studies reporting rates as
high as 1 tC ha-1 yr-1. Including fertilizer
savings, Eagle, et al.,\48\ estimate a net potential carbon benefit of
0.37 tC ha-1 yr-1 for winter cover crop use in
the U.S., not including CO2 and nitrous oxide savings from
reduced nitrogen fertilizer use, which they estimate could add another
0.16 tC ha-1 yr-1 of carbon savings. Poeplau and
Don's \65\ analysis suggest a new soil carbon equilibrium is reached
after 155 years; \9\ the reduced CO2 and nitrous oxide
savings from reduced nitrogen fertilizer use, where it occurs, would
last indefinitely. For a variety of reasons, including additional seed
and labor expenses as well as the risk of not killing the cover crop in
a timely manner, cover crops are planted today on only 3% of U.S.
cropland.\66\
Cropland Management: Diversifying Crop Rotations
Crop species vary in the amount of biomass they produce, in the
proportion of biomass that goes unharvested, including roots, and in
the resistance of unharvested residue to decomposition. Thus,
diversifying crop rotations is a time-tested means to build and retain
soil carbon. In the U.S. as early as 1933 Salter and Green \67\
reported on a 31 year experiment in which more complex rotations
retained more soil carbon. In central Ohio they found that continuous
corn (corn planted year after year) lost three times more soil carbon
than did a 3 year corn-wheat-oats rotation; continuous wheat and
continuous oats similarly lost twice as much carbon as did the 3 year
rotation (Figure 3).
Figure 3
Rotation effects on soil carbon maintenance over a 31 year
experiment. Redrawn from Salter and Green (1933).\58\
Diversifying annual crop rotations can thus significantly increase
carbon stores.50, 60, 68 The addition of perennial species
such as hay and alfalfa to annual crop rotations, because of the deep
and persistent roots of perennial crops and their longer growing
season, can boost soil carbon still further,\42\ as can the inclusion
of legumes such as clover.\69\ Measurements of soil carbon change under
more diverse annual cropping systems range from 0.02 to 1.1 tC
ha-1 yr-1,46, 50, 70, 71 but results
are highly dependent on associated full-rotation changes in crop
residues, tillage, and other factors that affect soil carbon stores. In
consideration of these unknowns, Eagle, et al.,\48\ estimate an average
net carbon benefit of 0.05 tC ha-1 yr-1 for
diversifying crop rotations to a sequence more complex than corn--
soybean, mainly achieved by lower nitrous oxide emissions.
Cropland Management: Manure and Compost Addition
Organic materials such as compost and manure, when added to
productive soils, tend to increase soil carbon stocks only as long as
additions are sustained.\27\ Added to less productive soils, however,
benefits can persist because of their additional impact on soil water
holding capacity, porosity, aeration, infiltration, and nutrient
holding capacity. These soil fertility co-benefits can increase crop
productivity and subsequent residue inputs. Thus, while the climate
benefit of moving compost or manure from one part of the landscape to
another must be considered,\72\ where soil fertility is sufficiently
improved to increase productivity the soil carbon gain is a legitimate
and persistent climate benefit.
In one recent example, Ryals, et al.,73, 74 added
compost to rangeland, which, exclusive of carbon in the compost
addition itself, appeared to increase soil carbon storage by 25-70% or
0.51-3.3 tC ha-1 3 years after a single compost
addition.\74\ Where manure is derived from crop harvest, which is the
case for most dairy and feed-lot cattle in the U.S., its return to soil
can be considered another form of crop residue return and thus also a
climate-legitimate carbon gain when compared to business-as-usual
practices. Estimates of soil carbon gain from long-term applications of
livestock manure to arable soils range from 0.2 to 0.53 tC
ha-1 yr-1.75, 76 Eagle, et al.,\48\
estimate a range of 0.05 to 1.4 for an average of 0.71 tC
ha-1 yr-1 that does not include CO2
savings from reduced nitrogen fertilizer use. Sequestration will likely
continue for the duration of manure additions, in our case >80 years--
the world's longest-running manure addition experiment has found soil
carbon stocks still increasing after 120 years,\77\ though stocks will
equilibrate to some lower level upon cessation.77, 78
3.2.2 Cropland Conversion to Perennial Grasses
Cropland Conversion: Set-aside Highly Erodible Cropland
Converting degraded or highly erodible cropland to perennial
grasslands has the potential to sequester soil carbon insofar as
perennial grasses have greater root carbon stocks than annual crops and
because they are grown without tillage. Nevertheless, such conversions
must be planned carefully to result in a legitimate climate benefit:
Converting annual cropland to perennial grassland has no climate
benefit where equivalent food production must be made up by more
intensive crop production elsewhere, especially if such displaced crop
production causes deforestation.\79\ Indirect land use change effects,
while disputed by some,\80\ are undoubtedly possible and can
potentially exceed local carbon savings.\81\
Nevertheless, USDA conservation programs that pay farmers to
convert privately-owned annual cropland with conservation value (e.g.,
highly erodible land) to grasslands or trees can lead to significant
soil carbon savings as a valuable co-benefit. For example, around 9 Mha
are currently enrolled in the U.S. Conservation Reserve Program, down
from a high of 15 Mha in 2007.\82\ Sperow, et al.,\83\ estimate that an
additional 30 Mha could be added to the 9 Mha currently enrolled based
on a USDA erodibility index.
Several recent reviews of soil carbon gain on conversion of annual
grain to perennial grasses report average carbon sequestration
potentials that range from 0.28-1.3 tC ha-1
yr-1.84-87 Including the upstream savings from
reduced agronomic inputs and nitrous oxide emissions (but not fossil
fuel carbon offsets), Eagle, et al.,\48\ estimate an average carbon
benefit of 0.97 tC ha-1 yr-1.
Cropland Conversion: Cellulosic Bioenergy on Grain Ethanol Lands
Where annual crops are currently used for grain-based biofuel
production, conversion to dedicated cellulosic feedstocks such as
perennial grasses could likewise sequester soil carbon and in this case
without potential indirect land use change effects. Cellulosic
feedstocks would additionally provide greater life cycle carbon savings
than the grain-based feedstocks they would replace.\88\ In 2017 38% of
total U.S. corn acreage, or 13 Mha, was used for grain ethanol
production; \89\ converting this cropland to a perennial cellulosic
crop would result in carbon savings additional to those from no-till
conversion (assuming conversion from no-till to avoid double counting
the no-till and perennial conversion benefits).
The rate of soil carbon gain for annual cropland converted to
perennial biofuel crops would be similar to that for set-aside cropland
(0.97 tC ha-1 yr-1). This assumes little of the
converted annual cropland was under permanent no-till management (see
Section 3.2.1, above).
Cropland Conversion: Cellulosic Bioenergy on Former Cropland
The potential for additional mitigation from planting marginal
lands--former cropland now abandoned--to cellulosic biofuel crops is
also significant. Additional to the fossil fuel offset benefit is the
soil carbon gain, especially on soils abandoned due to low fertility.
Again, placement of such crops would need to avoid land with
significant standing carbon stocks such as forests and wetlands to
achieve a short-term climate benefit. Robertson, et al.,\88\ note that
about 55 Mha of the 70-100 Mha of cropland abandoned since 1900 that is
neither forest nor wetland would be needed to meet expected 2050
biofuel needs.\90\ Planting these lands to higher productivity grass
species would cause carbon accumulation additional to that already
occurring in these lands.
The rate of soil carbon gain for former cropland converted to
perennial biofuel crops would be similar to that for set-aside cropland
but discounted by the carbon gain already occurring under existing
unmanaged vegetation.\88\ Assuming that the managed grasses are about
twice as productive as the pre-existing vegetation, the discounted
credit is likely to be 50% of the grassland conversion credit of 0.97
tC ha-1 yr-1, or 0.48 tC ha-1
yr-1. This value does not include a fossil fuel offset
credit.
3.2.3 Grazing Lands Management
Grazing Lands Management: Improved Animal Stocking Rates
Grazing lands, whether planted pastures as are typical in the
eastern U.S., or extensive rangelands as are typical in the western
U.S., are dominated by perennial grasses managed without annual
tillage. Soil carbon stores can be improved significantly by increasing
plant productivity via improved attention to livestock stocking
rates.86 On rangelands, estimates of soil carbon increases resulting
from improved stocking rates range from 0.07 to 0.31 tC ha-1
yr-1,91, 92 with higher rates for the Rocky
Mountains and Great Plains region. In a new meta-analysis of some 50
studies, Conant, et al.,\86\ estimate an average soil carbon
sequestration potential for improved stocking management on extensive
rangelands of 0.28 tC ha-1 yr-1. Because of a
relatively low sequestration rate, time to equilibration will likely
exceed 80 years.
On pasturelands, Eagle, et al.,\48\ note the potential for
intensive rotational grazing to improve soil carbon storage due to
increased plant productivity and careful attention to stocking rates.
The average sequestration rate for the few available published studies
is 0.25 tC ha-1 yr-1.
Grazing Lands Management: Improved Plant Species Composition
Grazing lands carbon sequestration can also be increased by
improving grass species composition. Interseeding legumes such as
alfalfa on rangeland \93\ can increase long-term carbon accrual by 3.1
tC ha-1 yr-1, and interseeding improved grass
species can improve average soil C by similar amounts.\94\ Eagle, et
al.,\48\ estimate an average soil carbon gain of 0.40 tC
ha-1 yr-1 for improved species composition on
rangelands. Henderson, et al.,\95\ estimate an average gain of 0.56 tC
ha-1 yr-1 for planting legumes in pastures, even
after decrementing rates for increased nitrous oxide emissions.
3.2.4 Frontier Technologies
There are unconventional technologies also under study for
increasing carbon removal and storage through agricultural land
management practices, some more mature than others. While these
practices may eventually prove to increase the carbon sequestration
potential within the U.S., I do not include these technologies in my
quantitative assessment of negative emissions because their feasibility
and benefits are yet too uncertain. The technologies include, but are
not limited to:
(1) Very high animal stocking rates on extensive rangeland for short
periods of time, known by a number of names including
intensive rotational grazing (as for pasturelands) and mob
grazing, have shown promise for improving productivity and
soil carbon stocks. In at least one study additional soil
carbon accumulation was 3 tC ha-1
yr-1 compared to continuous grazing.\96\ These
results are too early to generalize, however,\97\ and
recommendations await the results of further
experimentation.
(2) Biochar additions to soils have shown, in many cases, a
propensity to increase long-term soil stocks via direct
carbon stock change and improved soil fertility that, like
compost, can boost productivity in degraded or infertile
soils. Biochar is charcoal: a pyrolysis byproduct of the
thermochemical conversion of wood to other energy products
such as biogas and liquid bio-oil.\98\ Most biochar is
highly resistant to microbial attack, and additions to a
wide variety of soils have demonstrated its general
tendency to persist-indeed, many soils of fire-prone
ecosystems in the U.S. contain substantial amounts of
natural biochar.\99\
But biochar additions can also enhance the decomposition of native
soil organic matter,100, 101 offsetting the soil carbon
benefit of biochar itself, and as well biochar may be of greater
mitigation value if converted directly to energy to offset fossil fuel
use.\8\ A biochar recommendation awaits further research to clarify
both the long-term soil carbon gain in field studies and life cycle
carbon analysis in comparison to alternative uses.
3.2.5 Wetlands Restoration
Wetlands Restoration: Histosols
Histosols are soils high in organic matter due to their formation
under waterlogged conditions that inhibit microbial activity. As
wetland plants such as sphagnum moss produce biomass, a significant
fraction accumulates as peat and high-carbon sediments. When drained
for agriculture, histosols tend to be extremely productive, but once
exposed to oxygen, microbial activity accelerates and histosols can
lose carbon quickly at rates as high as 20 tC ha-1
yr-1.\102\ About 8% of histosol soils in the U.S. have been
drained for agriculture, mostly in Florida, Michigan, Wisconsin,
Minnesota, and California.
Carbon accumulation in these soils can be restored (carbon loss
reversed) by taking them out of production and restoring the high water
table. Although restoring wetland conditions will also restore methane
production, the combination of reversed carbon loss and abated nitrous
oxide emissions usually will exceed the additional methane loss,
leading to a large net emissions reduction.\103\ However, the area of
cultivated histosols soils is relatively small in the U.S.--used mostly
for vegetables and sugar cane production--so the overall mitigation
potential is modest.\24\ And as for cropland conversion to perennial
grasslands, care must be taken to avoid indirect land use change
effects. In 2017, the USDA paid farmers to maintain 0.8 Mha of restored
wetlands \32\ through the Farmable Wetlands Program (https://
www.fsa.usda.gov/programs-and-services/conservation-programs/farmable-
wetlands) within the Conservation Reserve Program (see Section 3.2); at
least another 0.8 Mha is readily available.\48\
Estimates of carbon gain under restored histosols vary widely, from
0.6 to 20 tC ha-1 yr-1.48 An average value,
considering other greenhouse gas impacts such as increased methane
emissions, was estimated by Alm, et al.,\104\ to be around 2.7 tC
ha-1 yr-1 for Finnish peatlands; more recently
Griscom, et al.,\9\ suggest an average value from a global peatlands
database of 3.65 tC ha-1 yr-1.
Wetlands Restoration: Non-Histosols
A substantial fraction of non-histosol wetlands have been drained
for agriculture in the U.S., and despite being below the threshold for
definition as histosols, prior to agricultural conversion they
generally had higher soil organic matter content than well-drained
soils. About 80% of wetland drainage in the U.S. has been attributed to
agriculture, or 32 Mha since 1780. Estimates of soil carbon
accumulation upon restoration are highly uncertain but in the range of
0.41 tC ha-1 yr-1,\105\ much smaller than for
histosol wetlands with their substantially greater soil carbon content,
and in the range that could be offset by increased methane emissions.
Thus it is not yet clear whether non-histosol wetland restoration is an
effective carbon sequestration strategy.
3.2.6 Forest Management
Forests, like croplands and grazing lands, can be managed to
enhance carbon sequestration via changes to forestry practices or by
conserving standing forests. Generally forest management includes
reforestation, which refers to the reestablishment of trees following
forest harvest, but does not include afforestation, defined by IPCC
\105\ as the establishment of trees on lands that have been deforested
for 50 years or more. In the U.S., afforestation largely comes at the
expense of current crop and pasturelands \106\ and thus will create
indirect land use change effects elsewhere, likely resulting in little
if any net climate benefit.107, 108 About 42% of total
forestland in the conterminous U.S. is publicly owned and managed by
Federal agencies.
Forest Management: Improved Stand Management
Improved forest management designed to enhance carbon sequestration
in tree biomass includes choices of tree species (fast versus slow
growing), harvest age or rotation length, and the use of practices such
as fertilization, controlled burning, and thinning to increase forest
productivity and carbon storage. Delaying rotation increases carbon
storage because carbon continues to accumulate as the trees grow;
109, 110 even relatively old growth forests continue to
accumulate carbon in soil stocks, including carbon in slow-to-decay
fallen trees on the forest floor.111, 112 But even without
additional carbon sequestration, preservation of an existing forest
biomass stock keeps it from the atmosphere for the period delayed.
Rotation lengths differ regionally by tree species and ownership
and can be managed readily. Softwoods and mixed species in
nonindustrial private forests of the southern U.S. are typically
managed on rotations of 25 to 35 years or longer, although rotations in
commercial forestry may be half this length.\113\ In the western U.S.,
commercial rotations tend to be 45-60 years because of longer-lived
species.
Delaying harvest and converting unmanaged forests to faster-growing
species to increase forest productivity can sequester, on average, 1.4-
2.1 tC ha-1 yr-1.113, 114 Using an
economic model, the U.S. Environmental Protection Agency (EPA)106
estimated that 7-105 MtC yr-1 (0.07-0.105 Gt C
yr-1) could be stored by all forests in the conterminous
U.S. at carbon prices from $1 to $50 per tCO2 for 100 years
or more; at a conservative $15 per tCO2,\8\ this amounts to
60 MtC yr-1. Their variable price economic model yields a 55
MtC yr-1 average by mid-century, which is consistent with
Griscom, et al.'s,\9\ U.S. projection of 18 MtC yr-1, not
including planted forests nor fire management, which they consider
alone could avoid 11 tC ha-1 yr-1 of carbon loss
in fire-prone forests such as those in the western U.S.
Reforestation, not considered here because of overlap with marginal
lands included in cellulosic biofuel estimates (Sections 3.2.2 and
4.2.4), could also provide substantial negative emissions. Griscom, et
al., project potential sequestration of 98 MtC yr-1 were all
once-forested U.S. pastureland, mostly east of the Missouri River and
including lands currently grazed, reforested. Such a strategy, however,
would require diet shifts away from meat to avoid indirect land use
effects, whereby displaced food production results in conversion of
natural areas (with its carbon loss) elsewhere, such as Amazonia. On
the other hand, reforestation on marginal lands not used for grazing
could provide carbon benefits similar to conversion to cellulosic
biofuels once biofuels were no longer used for fossil fuel
displacement.\115\
Forest Management: Improved Soil Management
Soil carbon stocks in U.S. forests are, in aggregate, substantial;
\116\ about 50% of the carbon in U.S. forests is in the soil and
another 8% in detrital material on the forest floor.\117\ Various
activities can affect forest soil carbon storage: rotation length,
harvest intensity, and fire management are among the most important.
Kimble, et al.,\117\ estimate that in total, U.S. forests managed for
timber could sequester 25 to 103 MtC yr-1 (0.25-0.103 GtC
yr-1), for average sequestration rates of 0.12-0.51 tC
ha-1 yr-1, or a mean of 0.32 tC ha-1
yr-1, a more conservative rate than earlier IPCC \105\
estimates for temperate forests of 0.53 tC ha-1
yr-1. This sequestration would be additional to the current
U.S. forest soil background sink recently estimated \118\ at 13-21 MtC
yr-1. Kimble, et al.,\119\ further estimate that soils under
agroforestry systems--e.g., alleycrops, riparian buffers, windbreaks,
and urban forests--could sequester nationally another 17-28 MtC
yr-1, or an average of 22.5 MtC yr-1.
4.0 Agricultural Greenhouse Gas Abatement by Land Management
4.1 Measuring Nitrous Oxide and Methane Fluxes
Nitrous oxide and methane, like CO2, are naturally
occurring greenhouse gases. They are distinguished in part by their
substantial global warming potentials, the degree to which they are
responsible for radiative forcing of the atmosphere compared to
CO2. Over a 100 year time horizon, nitrous oxide has 265-300
times the global warming potential of CO2, and methane 28-
36.10, 120 Another way of thinking about global warming
potentials is that 1 Mt of avoided nitrous oxide emission is equivalent
to 265-300 Mt of sequestered CO2. Thus, though their
atmospheric concentrations are substantially lower than those of
CO2, they pack significant punch and concentrations of each
have risen by about 45% since 1970.\1\ In order to directly compare the
atmospheric impact of all three gases, emissions of nitrous oxide and
methane are multiplied by 298 and 25, respectively,\102\ and expressed
as CO2 or carbon equivalents (CO2eq or Ceq).
Nitrous oxide is naturally emitted by bacteria in soils and other
environments as a byproduct of their nitrogen metabolism. Some nitrous
oxide is also emitted naturally from fires. Agriculture is responsible
for 84% of anthropogenic nitrous oxide emissions,\121\ and most
agricultural emissions (62%) come from soils amended with nitrogen from
fertilizers, manures, or legumes. Thus a major mitigation opportunity
related to land management is improved nitrogen fertilizer efficiency.
Agricultural methane emissions come from enteric fermentation by
livestock (52%), rice cultivation (22%), biomass burning (19%), and
livestock manure handling (8%).\121\ From the standpoint of land
management, rice cultivation offers today a substantial cropland
mitigation opportunity where rice is grown.
The non-CO2 greenhouse gas exchanges with the atmosphere
(fluxes) are not easily quantified. Most of what we know comes from
thousands of gas flux measurements made from small chambers (often 25-
30 cm diameter) placed on the soil surface. As gases accumulate in the
chamber, over the course of an hour or 2 gas samples are withdrawn and
analyzed for nitrous oxide or methane. The rates of gas accumulation
are calculated from these samples and represent net emissions.\122\
Like soil carbon, the spatial variability of fluxes from soil is
very high. Consequently, evaluations of abatement by different
agricultural practices are usually made in experimental plots to
isolate the effect of the practice from natural soil variability. Such
comparisons provide a high degree of confidence when they are made at
appropriate times: unlike soil carbon stocks, gas fluxes are also
highly variable in time. It's thus important to compare fluxes during
periods of low fluxes and high fluxes, and sampling campaigns are
expensive because of this need for frequent sampling. Nevertheless,
nitrous oxide and methane fluxes have been measured in agricultural
systems for over 40 years, and we have a reasonable understanding of
the major factors that regulate fluxes and can identify a number of
mitigation paths.
4.2 Avoided Emissions by Improved Land Management
4.2.1 Reduced Nitrous Oxide Emissions from Field Crops
About 50% of anthropogenic nitrous oxide emissions are from
nitrogen-fertilized field crops such as corn and wheat, where natural
soil bacteria that produce nitrous oxide are stimulated by more
available soil nitrogen. While factors other than fertilizer can also
accelerate nitrous oxide production, it has been known from field
studies since the 1970s 123-125 that nitrogen fertilizers
are responsible for most agricultural nitrous oxide emissions (e.g.,
Figure 4). In fact, most IPCC national greenhouse gas inventories tally
agricultural nitrous oxide emissions as a fixed percentage of nitrogen
fertilizer use.126, 127 Recent evidence that N2O
emissions increase exponentially with nitrogen fertilizer additions in
excess of crop need 128, 129 places even more importance on
fertilizer nitrogen rate as a predictor of agricultural emissions; this
exponential increase is incorporated in both commercial greenhouse gas
reduction protocols 130, 131 and in USDA protocols for
quantifying farm-level emissions.\132\ These protocols are now being
built into the COMET-Farm tool that allows farmers and ranchers to
calculate the greenhouse gas impacts of current and projected
practices.\133\
Figure 4
Nitrous oxide (N2O) emission response to nitrogen
fertilizer. Redrawn from Brietenbeck, et al., (1980).\111\
While other management interventions are also known to reduce
nitrous oxide emissions at specific locations,\132\ reducing nitrogen
fertilizer inputs to the rate needed for optimum yields (called by
agronomists the economically optimum rate) is the most reliable means
to reduce nitrous oxide emissions from fertilized cropping
systems.\134\ Carbon equivalent savings for a 15-20% increase in
fertilizer use efficiency (equivalent to a 15-20% reduction in average
nitrogen fertilizer use) in rainfed crops range from 0.15 to 0.29
tCeq ha-1 yr-1.103, 134-136
Millar, et al.,\134\ used an optimum fertilizer rate calculator to
show that nitrogen fertilizer rates on corn could be reduced for seven
Midwest states by at least 15% without affecting yields. A 15%
reduction represents an average avoided nitrous oxide emission of 2.2
kg N2O ha-1 yr-1, equivalent to 0.18
tCeq ha-1 yr-1 assuming a conservative
emission factor of 0.017 kg of nitrous oxide nitrogen per kg of
nitrogen fertilizer applied.\129\ In 2014 the U.S. consumed 13.3 Mt of
fertilizer N; \137\ a 15% savings (2.0 Mt N) would additionally save
15% of the CO2 cost of manufacture, equivalent to 2.2 MtC
yr-1 (0.0022 GtC yr-1) at a fertilizer production
cost of 4 kg CO2 per kg of nitrogen.\138\
At midcentury, others 139, 140 project a 50% increase in
nitrogen fertilizer use efficiency, from 53% today to 75% in the
future. If implemented immediately, this would lead to a 32% reduction
in nitrogen fertilizer use,\9\ for avoided nitrous oxide emissions of
0.36 tCeq ha-1 yr-1 and avoided
CO2 from fertilizer production of 2.2 Mt C yr-1.
Cropland affected by this savings is assumed to be that planted to
crops in 2012 (139 Mha) less the acreage in soybeans and peanuts,\141\
major commodity crops that require no nitrogen fertilizer.
4.2.2 Rice Water Management for Methane
Rice in the U.S. grows in flooded soils that create the oxygen-
depleted soil environment necessary for methane production. While rice
is not a major cereal crop in the U.S., annual rice-related methane
production is 3.1 GtCeq,\11\ about 2% of 2015 U.S. methane
emissions and about 2% of total worldwide methane production from
rice.\142\
Methane from flooded rice is most readily controlled by periodic
drainage. Sass, et al.,\143\ documented a 50% reduction in emissions in
Texas with a single mid-harvest drainage, and almost complete cessation
with a 2 day drainage every 3 weeks. Others have found similar
responses around the world, particularly in China.\144\ Eagle, et
al.,\145\ suggest a U.S. rice methane mitigation potential of 0.54
tCeq ha-1 yr-1 based on improved
drainage practices. Additional mitigation can be achieved with new
high-yielding rice cultivars that increase root zone porosity and
consequent methane oxidation.\146\
4.2.3 Cellulosic Bioenergy Production on Grain Ethanol Lands
As noted earlier, about 44% of U.S. corn acreage is currently used
for grain-based ethanol production. Were this acreage turned to biomass
production for cellulose-based ethanol production, using technology
that is currently in commercial use in the U.S., the climate benefit of
ethanol production would be substantially improved because the
production of cellulosic biomass crops like switchgrass require very
few fossil fuel inputs, unlike the production of corn grain. Whereas
grain-based ethanol avoids only 18% of the CO2eq that would
otherwise be emitted by gasoline, cellulosic ethanol avoids nearly
90%.147, 148 Thus, substituting cellulosic feedstocks such
as switchgrass on current corn grain ethanol cropland could provide a
substantially greater fossil fuel offset than grain ethanol feedstocks,
in addition to providing soil carbon sequestration as noted above in
Section 3.2.
The additional climate benefit can be calculated from a standard
life cycle analysis model such as GREET.149, 150 Not
including the soil carbon benefit already considered above, switchgrass
with a conservative biomass yield of 8 Mg ha-1
yr-1 can provide 1.44 tC ha-1 yr-1 of
fossil fuel CO2 savings when converted to
ethanol.150, 151 The difference from corn grain (0.73 tC
ha-1 yr-1 for a grain biomass yield of 11 Mg
ha-1 yr-1) represents a net avoided
CO2 emission benefit of 0.71 tC ha-1
yr-1. The difference would be greater with a higher yielding
cellulosic biomass crop.
4.2.4 Cellulosic Bioenergy Production on Marginal Lands
Cellulosic biofuels can also be grown on former agricultural lands,
as noted earlier. To meet expected 2050 liquid transportation fuel
demands requires 55 Mha of the 70-100 Mha of crop and pastureland
abandoned from agriculture since 1900, excluding urban, forest, and
wetlands.\88\ Planting this acreage to switchgrass with an avoided
CO2 emission benefit of 1.08 tC ha-1
yr-1 for an average 6 Mg ha-1 yr-1
yield 150, 151 would generate a significant avoided
CO2 emissions savings. This value does not include the soil
carbon sequestration included as negative emissions. Note that this is
not BECCS, insofar as the carbon in the fuel is not geologically
sequestered as CO2.
5.0 Total Mitigation Potentials
Several published studies have estimated a total biophysical
potential for soil carbon sequestration globally and in the United
States with land management technologies that are currently available.
Before summarizing the U.S. carbon mitigation potential it is worth
considering the global perspective.
5.1 Global Estimates of Potentials for Soil Carbon Gain
Recent global estimates of the biophysical potential for cropland
and grazing land soils to sequester carbon range from
0.4-1.5 GtC yr-1 (Table
1).24, 105, 152-156 Each of the estimates in Table 1 assume
adoption of some combination of improved cropland and grazing land
management, agroforestry, and restoration of degraded lands and
histosol wetlands. Note that they do not include other sequestration
practices described above, including sequestration due to improved
forest management and conversion of grain ethanol lands to cellulosic
biofuel crops, nor savings from avoided emissions such as those from
improved nitrogen fertilizer use. That these global estimates are
similar to one another arises from considering the same types of
practices and using similar well-constrained field estimates that are
based on long-term experiments for major mitigation practices such as
no-till.
To calculate the total century-long mitigation potential requires
knowing for how long these rates are sustainable. As noted earlier,
soil carbon accumulation tends to behave asymptotically--after some
period maximum rates slow until a new equilibrium is reached (Figure
2). Although very long term experiments in agricultural systems are
rare, it's clear that the applicable period likely differs among
management practices, climate zones, and initial soil carbon levels.
Many researchers assume conservatively that average maximum rates occur
for at least 20 years with the rate of sequestration after then
declining to a new steady state that occurs about 40 years post
management change,28, 44 although some (e.g.,\152\) assume
>50 years persistence. A 30 year period at average sequestration rates
seems a reasonable working value and is the value I have used for the
calculations contained in this report.
Table 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Set-aside of
Estimate Improved Improved erodible Restoration of Restored peat
Year (GtCeq yr 1) cropland grazing land cropland to degraded land Agroforestry soils Reference
management management grassland
--------------------------------------------------------------------------------------------------------------------------------------------------------
1998 0.4-0.9 X X X Paustian, et al.\152\
1999 0.5-0.6 X X Lal and Bruce \153\
2000 0.82 X X X X X IPCC \105\
2004 0.4-1.2 X X X X X Lal \154\
2008 1.4-1.5 X X X X X Smith, et al.\103\
2014 0.7-1.4 X X X X X Sommer and Bossio \156\
2016 0.3-1.5 X X X X X X Paustian, et al.\24\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Published estimates of global soil carbon sequestration potentials based on biophysical processes that could be enhanced by land management actions. Not
included are sequestration potentials from forest management, cellulosic biofuel crops, or carbon additions such as compost or biochar, nor savings
from avoided emissions such as those from avoided nitrogen fertilizer use.
If the average global sequestration rate of 1.2 GtC yr-1
for the three most recent analyses 24, 155, 156 is
multiplied by a conservative 30 year sequestration period, then we can
calculate an end-of-century value of 36 GtC sequestered for this set
of soil carbon practices.
Expanding the scope to include forests and coastal wetlands readily
boosts global negative emissions potentials well past the 100 GtC end-
of-century target for restoring a 350 ppm CO2 atmosphere.\4\
In one recent analysis Griscom, et al.,\9\ consider at the global scale
20 conservation, restoration, and land management actions that, in
aggregate, could sequester or avoid as much as 6.5 GtC yr-1
for at least a 25 year period. They include aggressive reforestation,
forest management, coastal wetland and peatland restoration, and Table
1 practices to yield 169 GtC of negative emissions by the year 2100 if
implemented soon. If reforestation were to more reasonably include
reforesting only 25% of the once-forested areas, rather than 100%,
their estimate reduces to 148 GtC by 2100.
Avoided emissions, including stopping deforestation and wood fuel
harvest, improved nitrogen fertilizer management, and avoided coastal
wetland and peatland conversion provides another 128 GtC of savings,
for a global end-of-century total of 276 GtC.
It is worth emphasizing that these practices are feasible and
available for implementation today, and would provide land-based
CO2 mitigation additional to the existing 2.6 GtC
yr-1 land sink (Section 2.0).
Including frontier technologies such as biochar additions and the
development of microbiome-assisted carbon accrual could further
increase soil carbon sequestration potentials, perhaps by as much as
1.8 fold.\24\ Worth noting too is the French Government's ``4 per
mille'' initiative announced at the time of the 2016 Paris climate
accord,\157\ which aims to increase global soil carbon stocks by 0.4%
per year, an aspirational goal equivalent to sequestration rates of 3.4
GtCeq yr-1 (272 GtC if sustained through 2100)
that has attracted significant attention.158-160 Many,
myself included, feel this rate is overambitious in part because we
don't know the saturation potentials for most soils, but the initiative
has raised awareness and will likely spur further research to identify
additional soil carbon management interventions.
5.2 U.S. Potentials for Negative and Avoided Emissions by Land
Management Change
Table 2 presents a summary synthesis of the management practices
identified in the sections above for the U.S. Negative emissions,
including Cropland management (Section 3.2.1), Cropland conversion to
perennial grasses (3.2.2), Grazing land management (3.2.3), Wetland
histosols restoration (3.2.4), and Forest management (3.2.6), sum to a
potential total carbon storage rate of 414 MtCeq
yr-1 (0.414 GtCeq yr-1).
This rate is similar to those calculated for other recent U.S.
summaries 28, 83, 159, 161 when considering individual
practices. While other syntheses estimate a lower range of 75-174
MtCeq yr-1, with an average rate of 85
MtCeq yr-1, they do not include carbon
sequestered due to improved forest management or the establishment of
cellulosic bioenergy crops. These alone add 198 MtCeq
yr-1. A 2007 Congressional Budget Office analysis \162\ that
included forest management estimated a 2030 sequestration potential of
479 MtCeq yr-1. Thus the present analysis
(summing to 414 MtCeq yr-1 for negative
emissions) is consistent with earlier analyses.
As noted earlier, the duration of individual sequestration rates by
different practices differ. Sequestration rates for all practices could
be sustained for at least 30 years, and some for 50-80 years or more as
noted in Section 5.1. With these durations, total negative emissions
sum to 20.9 GtCeq through 2100 (Table 2).
Avoided emissions are also additional in the present analysis.
These include (a) improved fertilizer efficiency (Section 4.2.1), (b)
rice water management for methane (4.2.2), and (c) cellulosic bioenergy
production (Sections 4.2.3 and 4.2.4). These provide additional
mitigation potentials that themselves sum to an annual capacity of 122
MtCeq yr-1 (0.122 GtCeq
yr-1), totaling 9.7 GtCeq through 2100 (Table 2).
It is worth noting that the capacity of these activities is on-going
and permanent, i.e. most of their carbon benefits are not subject to
saturation as are biological carbon sinks, nor subject to re-emission
upon management change or natural disturbance such as forest fires. It
is also worth noting that, except for cellulosic biofuels, there is
likely no overlap with decarbonization pathways for energy use. Should,
however, energy analyses include cellulosic biofuel production at the
magnitude noted here, then the avoided emissions here (72 MtC
yr-1 or 5.7 GtC for 80 years) would be double counted so
this total should be appropriately discounted. The negative emissions
due to cellulosic biofuels--soil carbon capture--does not contribute to
avoided fossil fuel use so should remain part of this total.
Table 2
----------------------------------------------------------------------------------------------------------------
Local rate
Practice change (tCeq ha 1 Areal extent Annual total Duration (yr) Yr 2100 total
yr 1) (Mha) (MtCeq yr 1) (GtCeq)
----------------------------------------------------------------------------------------------------------------
Negative emissions
Cropland management (3.2.1)
No till adoption 0.40 a 94 37.6 30 1.13
Reduced summer fallow 0.09 a 20 1.8 30 0.05
Winter cover crops 0.52 a 66 34.3 80f 2.75
Diversified crop rotations 0.05 a 46 2.3 80 0.18
Manure & compost additions 0.71 a 8.5 6.0 80 0.48
Cropland conversion to
perennial grasses (3.2.2)
Set-aside highly erodible 0.97 b 26 25.2 30 0.76
cropland
Cellulosic bioenergy on 0.97 c 13 12.6 30 0.38
grain ethanol lands
Cellulosic bioenergy on 0.48 d 55 26.4 30 0.79
marginal lands
Grazing land management
(3.2.3)
Improved stocking rates on 0.28 e 216 60.5 80 4.84
rangeland
Improved species composition 0.56 a 80 44.8 30 1.34
Wetland histosol restoration 3.65 a 0.8 2.9 80 0.23
(3.2.4)
Forest management (3.2.6)
Improved soil management-- 0.32 e 256 81.9 50 4.10
timberland
Improved soil management-- 22.5 50 1.13
agroforestry
Improved stand management 55.0 50 2.75
---------------- ---------------
Subtotal--Negative 414 20.9
emissions
---------------- ---------------
Avoided emissions
Improved fertilizer efficiency
(4.2.1)
Avoided nitrous oxide 0.36 c 125 45.0 80 3.60
emissions
Avoided CO2--fertilizer 4.4 80 0.35
production
Rice water management for 0.54 a 1.3 0.7 80 0.06
methane (4.2.2)
Cellulosic bioenergy
production
Production on grain ethanol 0.71 c 17 12.1 80 0.97
lands (4.2.3)
Production on marginal lands 1.08 d 55 59.4 80 4.75
(4.2.4)
---------------- ---------------
Subtotal--Avoided 122 9.7
emissions
================ ===============
Total potential 535 30.6
----------------------------------------------------------------------------------------------------------------
Potential sources and magnitude of U.S. greenhouse gas mitigation from changes in land management practices that
lead to negative emissions (carbon storage) and avoided emissions for the period 2020-2100. Numbers in
parentheses refer to sections in text for local sequestration values.
a Eagle, et al.48, 145.
b Sperow, et al.83.
c ERS \89\.
d Robertson, et al.\88\.
e Bigelow and Borchers \29\.
f Poeplau and Don \65\.
g USDA \163\.
Assuming no overlap, and over an 80 year end-of-century lifetime,
then, these avoided emissions practices sum to 9.7 GtCeq
through 2100.
Altogether, then, I conclude that U.S. potentials for mitigating
greenhouse gas emissions through negative emissions due to land
management practices on forest, range and crop lands in the
conterminous U.S. sum to 20.9 GtCeq for the period 2020-
2100. This represents more than 20% of the global natural sequestration
target needed to bring CO2 concentrations to 350 ppm.\4\
Including avoided emissions due to land management practices brings the
sum to 30.6 GtCeq for the period 2020-2100, or >30% of the
total needed.
That the Federal Government manages 43% of rangeland and 44% of
forests in the conterminous U.S. (see Section 3.2) allows an estimate
of the sequestration potential on public grazing and forest lands of
115 MtCeq yr-1, or 6.2 GtCeq through
2100. About 56% of this total is sequestration on forest lands, the
remainder on rangelands.
In its annual inventory of greenhouse gas emissions and sinks for
the U.S., the USEPA \11\ estimates for U.S. land management a
background sink of 212 MtCeq yr-1 (0.212
GtCeq yr-1) for 2015. The primary drivers of
these sinks in 2015 were forest growth (181 MtCeq
yr-1) and forestland expansion (21 MtCeq
yr-1), with urban tree growth and landfills (9
MtCeq yr-1) contributing most of the remaining
sink. Decrementing this by concomitant changes in methane and nitrous
oxide emissions brought the net land management sink to 207
MtCeq yr-1. The 535 MtCeq
yr-1 potential land management sink noted in Table 2 (both
negative and avoided emissions) is additional to this existing
background sink. Were the strategies in this report fully implemented,
a future USEPA inventory might tally a net U.S. sink close to 750
MtCeq yr-1 (0.750 GtCeq
yr-1).
5.3 Barriers that Prevent Optimized Biotic Greenhouse Gas Mitigation in
the U.S.
The principal barriers to adopting management practice changes to
mitigate greenhouse gas emissions in the U.S. are neither knowledge-
based nor technical. There is ample evidence, detailed and summarized
above, that land management changes can achieve real and verifiable
negative and avoided emissions with high confidence. The values in
Table 2 are, in general, conservative--they include values from field
observations and experiments conducted throughout the U.S. and similar
ecoregions, i.e., they are empirically-based, representative estimates
from farm, rangeland, and forest systems typical of the U.S. Further
research will lead to their refinement, but it seems unlikely that
average values will change more than 20-30%, and, importantly, the
values are in any case as likely to increase in magnitude as to
decrease. Further, as noted earlier, not all possible practices to
drive negative or avoided emissions are included.
Research and experience show that farmers, ranchers, and forest
managers who own and manage non-Federal lands are willing to accept
payments for providing ecosystem services such as soil organic matter
accrual, nitrate leaching avoidance, wetland protection, and greenhouse
gas avoidance.164, 165 For example, in 2017, USDA and its
partners worked with 680,000 land managers to fund the development of
conservation plans for 27 million acres of working lands.\166\ Both
research 164, 165, 167-169 and over-subscribed USDA
conservation programs point to farmers' and other landowners' openness
to accepting conservation and other ecosystem service payments through
a variety of mechanisms, including auctions. Thus, the principal
barrier for engaging landowners and managers is not feasibility or lack
of interest, but lack of policy support and financial incentive.
How much financial incentive is necessary? The success of USDA
conservation programs show that farmers and ranchers are willing to
accept relatively low payments for changing specific practices,
sometimes as low as a few dollars per acre. In many cases the payments
depend on cobenefits. Building soil carbon, for example, benefits soil
fertility, water holding capacity, and drainage, and experimental
auctions have shown lower payments would be required than, for example,
reducing nitrous oxide emissions, which are considered by farmers to
have fewer cobenefits.165, 170 Practices with higher
management costs--cover crops, for example--would likewise require
higher payments. That said, most analyses to date that include economic
costs conclude that many practices could be implemented at costs as low
as $10 per MtCO2 ($2.70 per MtC). Griscom, et al.,\9\ for
example, state that \1/3\ of the potentials they consider could be
provided at this cost, with the remainder requiring no more than $100
per MtCO2, which is consistent with the expected avoided
cost of holding warming to below 2 C by 2100.\171\ USEPA modeling
\106\ concludes that some forest and agricultural management practices
could be incentivized at carbon prices as low as $1 per
MtCO2, with full implementation at $50.
Various voluntary efforts such as the USDA Building Blocks for
Climate Smart Agriculture and Forestry (https://www.usda.gov/oce/
climate--change/buildingblocks.html) \172\ provide frameworks for
farmers, ranchers, and landowners to respond to climate change. For
example, the Building Blocks program provides a series of measures
intended to assist a wide variety of land management stakeholders to
increase carbon storage and reduce greenhouse gas emissions; ten
categories of activities range from soil health and nitrogen
stewardship to grazing and pastureland management. The program provides
case studies to inspire users and provides technical assistance through
NRCS and other USDA professionals to help individual land managers meet
personal greenhouse gas reduction goals. Only 3 years old, the
effectiveness of the Building Blocks initiative is largely untested but
it provides an evidence-based framework for engaging landowners and
managers in the sorts of meaningful activities identified herein. The
Building Blocks framework is an important start, but the quantitative
goal it contains (33 MtCeq yr-1 by 2025) is far
below the 535 MtCeq yr-1 identified in the
present analysis, and because the initiative is strictly voluntary with
no incentives, it is unlikely to meet even this goal.
More useful is the on-line COMET-Farm tool (http://cometfarm.nrel.
colostate.edu) \133\ that allows farmers and ranchers to calculate the
greenhouse gas impacts of current and projected land management
practices. Calculations are based on the USDA's methods for quantifying
farm-level emissions (https://www.usda.gov/oce/climate_change/
estimation.htm).\132\ Calculations are specific to individual fields as
identified by aerial and satellite imagery, and cover most of the crop
and grazing land practices in Sections 3.2 and 4.2, including avoided
emissions from improved nitrogen fertilizer management, all of which
make comparisons between business-as-usual and alternative practices
straightforward and directly relevant to the land being managed.
Likewise, national carbon registries offer a framework to provide
landowners and carbon markets detailed evidence-based protocols for
voluntarily quantifying the carbon captured or emissions avoided by
specific land management practices. Both the American Carbon Registry
(www.americancarbonregistry.org) and the Verified Carbon Standard
(www.verra.org), for example, provide protocols for awarding carbon
credits based on avoided nitrous oxide emissions by improved nitrogen
fertilizer management 130, 131 as well as avoided methane
emissions from improved rice management and wetland restoration.\173\
That said, scaling up sequestration nationwide on the order
discussed in the present report will require revisiting the many
Federal policies and incentives that influence agricultural, grazing,
and forestry practices on both private and public lands of the U.S.
Without supportive Federal policies and payments sufficient to cover
costs, farmers, ranchers, and forest owners are unlikely to participate
in sufficient numbers to effect meaningful change.
6.0 Concluding Opinions
Based upon a review of the literature, my own research, and in
consultation with other experts in the field, it is my expert opinion
that through improved land management practices, at a combined peak
rate of 535 MtCeq yr-1 (0.535 GtCeq
yr-1), about 31 GtCeq of additional emissions
could be sequestered and avoided by land management changes on U.S.
forestland, rangelands, and farms between 2020 and 2100. Some 21 GtC
could be provided by negative emissions, i.e., natural carbon removal
and storage by practices such as improved cropland and rangeland
management. Another 10 GtC could be provided by avoided emissions from
practices such as improved nitrogen management and cellulosic bioenergy
production. We have known for decades the potential for most of these
practices to contribute to negative or avoided emissions. Sequestration
on this scale would meet the scientific prescription for sequestration
set forth by Hansen, et al.4, 174, 175
Signed this 13th day of April, 2018 in Cambridge, UK.
G. Philip Robertson.
Exhibit D: Government Climate and Energy Actions, Plans, and Policies
Must Be Based on a Maximum Target of 350 ppm Atmospheric
CO2 and 1 C by 2100 to Protect Young People and
Future Generations
Introduction
Human laws can adapt to nature's laws, but the laws of nature will
not bend for human laws. Government climate and energy policies must be
based on the best available climate science to protect our climate
system and vital natural resources on which human survival and welfare
depend, and to ensure that young people's and future generations'
fundamental and inalienable human rights are protected.
Because carbon dioxide (CO2) is the primary driver of
climate destabilization and ocean warming and acidification, all
government policies regarding CO2 pollution and
CO2 sequestration should be aimed at reducing global
CO2 concentrations below 350 parts per million (ppm) by
2100. Global atmospheric CO2 levels, as of 2019, are
approximately 407 ppm and rising.\1\ An emission reductions and
sequestration pathway back to 350 ppm could limit peak warming to
approximately 1.3 C this century and stabilize long-term heating at 1
C above pre-industrial temperatures.
---------------------------------------------------------------------------
\1\ Ed Dlugokencky & Pieter Tans, NOAA/ESRL, www.esrl.noaa.gov/gmd/
ccgg/trends/.
---------------------------------------------------------------------------
As explained in more detail below, there are numerous scientific
bases and lines of evidence supporting setting 350 ppm and 1 C by 2100
as the uppermost safe limit for atmospheric CO2
concentrations and global warming. Beyond 2100, atmospheric
CO2 may need to return to below 300 ppm to prevent the
complete melting of Earth's ice sheets and protect coastal cities from
sea level rise. Fortunately, it is still not only technically and
economically feasible to return to those levels, but transitioning to
renewable energy sources will provide significant economic and public
health benefits and improve quality-of-life.
Why 350 ppm And 1 C Long-Term Warming?
Three lines of robust and conclusive scientific evidence, based on
the paleo-climate record and realworld observations show that above an
atmospheric CO2 concentration of 350 ppm there is: (1)
significant global energy imbalance; (2) massive ice sheet
destabilization and sea level rise; and (3) ocean warming and
acidification resulting in the bleaching death of coral reefs and other
marine life.
(1) Energy Balance
Earth's energy flow is out of balance. Because of a buildup of
CO2 in our atmosphere, due to human activities, primarily
the burning of fossil fuels and deforestation,\2\ more solar energy is
retained in our atmosphere and less energy is released back into
space.\3\ The energy imbalance of the Earth is roughly equivalent to
2500 Camp Creek \4\ fires per day burning around the world.\5\
Returning CO2 concentrations to below 350 ppm would restore
the energy balance of Earth by allowing as much heat to escape into
space as Earth retains, an important historic balance that has kept our
planet in the sweet spot for the past 10,000 years, supporting stable
sea levels, enabling productive agriculture, and allowing humans and
other species to thrive.\6\ The paleo-climate record shows that
CO2 levels, temperature, and sea level all move together
(see Figure 1). Humans have caused CO2 levels to shoot off
the chart (circled in red), rising to levels unprecedented over the
past 3 million years, and causing the energy imbalance.\7\
---------------------------------------------------------------------------
\2\ Intergovernmental Panel on Climate Change, Summary for
Policymakers, Climate Change 2014: Impacts, Adaptation, and
Vulnerability 5 (2014).
\3\ James Hansen, et al., Assessing ``Dangerous Climate Change'':
Required Reduction of Carbon Emissions to Protect Young People, Future
Generations and Nature, PLOS ONE 8:12 (2013) [hereinafter Assessing
``Dangerous Climate Change''].
\4\ The Camp Creek fire was the 2018 California fire, the deadliest
and most destructive in the state's history, that burned over 150,000
acres (almost 240 square miles).
\5\ Steven W. Running, Declaration in Support of Plaintiffs,
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-12-Running-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf),
No. 18-36082, Doc. 21-12 (9th Cir. Feb. 7, 2019).
\6\ James Hansen, Storms of My Grandchildren 166 (2009).
\7\ Willeit, et al., Mid-Pleistocene transition in glacial cycles
explained by declining CO2 and regolith removal. Science
Advances (2019).
---------------------------------------------------------------------------
Figure 1
Evidence from the paleo-climate record showing the
relationship between CO2 concentration, global
temperature, and sea level.
(2) Ice Sheets and Sea Level Rise
The last time the ice sheets appeared stable in the modern era was
in the 1980s when the atmospheric CO2 concentration was
below 350 ppm. The consequences of >350 ppm and 1 C of warming are
already visible, significant, and dangerous for humanity. With just 1
C of warming, glaciers in all regions of the world are shrinking, and
the rate at which they are melting is accelerating.\8\ Large parts of
the Greenland and Antarctic ice sheets, which required millennia to
grow, are teetering on the edge of irreversible disintegration, a point
that if reached, would lock-in major ice sheet mass loss, sea level
rise of many meters, and worldwide loss of coastal cities--a
consequence that would be irreversible on any timescale relevant to
humanity (see Figure 2).\9\ Greenland's ice sheet melt is currently
occurring faster than anytime during the last 3\1/2\ centuries, with a
33% increase alone since the 20th century.\10\ The paleo-climate record
shows the last time atmospheric CO2 levels were over 400
ppm, the seas were 70 higher than they are today and that heating
consistent with CO2 concentrations as low as 450 ppm may
have been enough to melt almost all of Antarctica.\11\ While many
experts are predicting multi-meter sea level rise this century, even
NOAA's modest estimate of 3-6 by 2100 would impact between 4 and 13
million Americans (see Figure 3).\12\
---------------------------------------------------------------------------
\8\ Zemp, et al., Global glacier mass changes and their
contributions to sea-level rise from 1961-2016. Nature (2019); B.
Menounos, Heterogeneous Changes in Western North American Glaciers
Linked to Decadal Variability in Zonal Wind Strength, Geophysical
Research Letters (2018).
\9\ Hansen, Assessing ``Dangerous Climate Change,'' at 13; see also
James Hansen, et al., Ice Melt, Sea Level Rise and Superstorms;
Evidence from Paleoclimate Data, Climate Modeling, and Modern
Observations that 2 C Global Warming Could be Dangerous, Atmos. Chem.
& Phys. 16, 3761 (2016) [hereinafter Ice Melt, Sea Level Rise and
Superstorms].
\10\ Trusel, L.D., et al., Nonlinear rise in Greenland runoff in
response to post-industrial Arctic warming, Nature (2018).
\11\ Dec. of Dr. James E. Hansen, Juliana,, et al., v. United
States, et al., No. 6:15-cv-01517-TC, 14 (D. Or. Aug. 12, 2015);
Intergovernmental Panel on Climate Change: 2007 Working Group I: The
Physical Science Basis, Chapter 6.3.2, What Does the Record of the Mid-
Pliocene Show?; Dowsett & Cronin, High eustatic sea level during the
middle Pliocene: Evidence from the southeastern U.S. Atlantic Coastal
Plain, Geology (1990); Shackleton, et al., Pliocene stable isotope
stratigraphy of ODP Site 846, Proceedings of the Ocean Drilling
Program, Scientific Results (1995).
\12\ NOAA, Examining Sea Level Rise Exposure for Future
Populations, https://coast.noaa.gov/digitalcoast/stories/population-
risk.
---------------------------------------------------------------------------
Figure 2
Antarctic melt water from the Nansen ice shelf.
Most climate models represent sea level rise as a gradual linear
response to melting ice sheets, but the historic climate record shows
something very different. In reality, seas do not rise slowly and
predictably but rather in quick pulses as ice sheets destabilize.\13\
Scientists believe we have a chance to preserve the large ice sheets of
Greenland and Antarctica and most of our shorelines and ecosystems if
we limit long-term warming by the end of the century to no more than 1
C above pre-industrial levels (short-term warming will inevitably
exceed 1 C but must not exceed 1 C for more than a short amount of
time).
---------------------------------------------------------------------------
\13\ Wanless, H.R., et al., Dynamics and Historical Evolution of
the Mangrove/Marsh Fringe Belt of Southwest Florida, in Response to
Sea-level History, Biogenic Processes, Storm Influences and Climatic
Fluctuations. Semi-annual Research Report (June 1993 to February 1994);
Hansen, Ice Melt, Sea Level Rise and Superstorms, at 3761; Hansen,
Assessing ``Dangerous Climate Change,'' at 20.
---------------------------------------------------------------------------
Figure 3
South Florida, including Miami, will face significant
inundation with 6 of sea level rise.
(3) Ocean Warming and Acidification
Our oceans have absorbed 93% of the excess heat in the atmosphere
trapped by greenhouse gases (see Figure 4) as well as approximately 30%
of CO2 emitted into the atmosphere, causing ocean
temperatures to surge and the ocean to become more acidic.\14\ Indeed,
our oceans are warming much more rapidly than previously-thought.\15\
Many marine ecosystems, and particularly coral reef ecosystems, cannot
tolerate the increased warning and acidity of ocean waters that result
from increased CO2 levels.\16\ At today's CO2
concentration, around 407 ppm,\17\ critically important ocean
ecosystems, such as coral reefs, are rapidly declining and will be
irreversibly damaged from high ocean temperatures and repeated mass
bleaching events if we do not quickly curtail emissions (see Figures 5
and 6).\18\ According to the Intergovernmental Panel on Climate Change,
bleaching events are occurring more frequently than the IPCC previously
projected and 70-90% of the world's coral reefs could disappear as soon
as 2030 (the IPCC also predicts 99% of coral reefs will die with 2 C
warming).\19\ Even the recent National Climate Assessment acknowledged
that coral reefs in Florida, Hawaii, Puerto Rico, and the U.S. Virgin
Islands have been harmed by mass bleaching and coral diseases and could
disappear by mid-century as a result of warming waters.\20\ Scientists
believe we can protect marine life and prevent massive bleaching and
die-off of coral reefs only by rapidly returning CO2 levels
to below 350 ppm.\21\
---------------------------------------------------------------------------
\14\ Hansen, Assessing ``Dangerous Climate Change,'' at 1; Climate
Change 2013: The Physical Science Basis. Contribution of Working Group
I to the Fifth Assessment Report of the Intergovernmental Panel on
Climate Change (Cambridge University Press, 2013); Cheng, et al., How
fast are the oceans warming? 363 Science 128 (2019); National Oceanic
and Atmospheric Administration, What is Ocean Acidification?, https://
oceanservice.noaa.gov/facts/acidification.html.
\15\ Cheng, L., et al., How fast are the oceans warming?, 363
Science 128 (2019).
\16\ Hughes, et al., Global warming impairs stock-recruitment
dynamics of corals, Nature (2019).
\17\ Ed Dlugokencky and Pieter Tans, NOAA/ESRL, www.esrl.noaa.gov/
gmd/ccgg/trends/.
\18\ Frieler, K., et al., Limiting global warming to 2 degrees C is
unlikely to save most coral reefs. Nature Climate Change 3: 165-170.
(2013); Veron, J.,, et al; The coral reef crisis: The critical
importance of <350ppm CO2. Marine Pollution Bulletin 58:
1428-1436 (2009); Hughes, T., et al., Spatial and temporal patterns of
mass bleaching of corals in the Anthropocene, Science 359: 80-83
(2018); Hughes, T., et al. Global warming impairs stock-recruitment
dynamics of corals, Nature (2019).
\19\ Hoegh-Guldberg, Ove, et al., Impacts of 1.5 C Global Warming
on Natural and Human Systems. In Global Warming of 1.5 C. An IPCC
Special Report on the impacts of global warming of 1.5 C above pre-
industrial levels and related global greenhouse gas emission pathways,
in the context of strengthening the global response to the threat of
climate change, sustainable development, and efforts to eradicate
poverty at pp. 225-226 (2018); IPCC, Summary for Policymakers of IPCC
Special Report on Global Warming of 1.5 C Approved by Governments
(2018).
\20\ Pershing, A.J., et al., Oceans and Marine Resources. In
Impacts, Risks, and Adaptation in the United States: Fourth National
Climate Assessment, Volume II, USGCRP (2018)[.]
\21\ Veron, J., et al., The coral reef crisis: The critical
importance of <350 ppm CO2, 58 Marine Pollution Bulletin
1428 (2009).
---------------------------------------------------------------------------
Figure 4
Over 90% of the excess energy from human caused climate
change has been absorbed by the oceans, adding energy to storms
and harming coral reefs around the globe.
No scientific institution, including the IPCC, has ever concluded
that 2 C warming or 450 ppm would be safe for ocean life. According to
Dr. Ove Hoegh-Guldberg, one of the world's leading experts on ocean
warming and acidification, and a Coordinating Lead Author on the
``Oceans'' chapter of the IPCC's Fifth Assessment Report and on the
``Impacts of 1.5 C global warming on natural and human systems'' of
the IPCC's Special Report on 1.5 C:
``Allowing a temperature rise of up to 2 C would seriously
jeopardize ocean life, and the income and livelihoods of those
who depend on healthy marine ecosystems. Indeed, the best
science available suggests that coral dominated reefs will
completely disappear if carbon dioxide concentrations exceed
much more than today's concentrations. Failing to restrict
further increases in atmospheric carbon dioxide will eliminate
coral reefs as we know them and will deny future generations of
children from enjoying these wonderful ecosystems.'' \22\
---------------------------------------------------------------------------
\22\ Id.
---------------------------------------------------------------------------
Figure 5
Healthy coral like this are already gravely threatened and
will likely die with warming of 1.5 C.
Figure 6
Bleached coral from warmer ocean temperatures.
Additional Observations Illustrate the Dangers of Increased Warming
In addition to the evidence discussed above which illustrates the
necessity of ensuring that the atmospheric CO2 concentration
returns to no more than 350 ppm, based on present day observations
about climate impacts occurring now, it is clear that the present level
of 1 C is already causing significant climate impacts and additional
warming will exacerbate these already dangerous impacts. Climate
impacts that are already being experienced today include:
Declining snowpack and rising temperatures are increasing
the length and severity of drought conditions, especially in
the western United States and Southwest, causing problems for
agriculture users, forcing some people to relocate, and leading
to water restrictions.\23\
---------------------------------------------------------------------------
\23\ Steven W. Running, Declaration in Support of Plaintiffs,
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-12-Running-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf),
No. 18-36082, Doc. 21-12 (9th Cir. Feb. 7, 2019).
In the western United States, the wildfire season is now
almost 3 months longer (87 days) than it was in the 1980s.\24\
---------------------------------------------------------------------------
\24\ Steven W. Running, Declaration in Support of Plaintiffs,
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-12-Running-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf),
No. 18-36082, Doc. 21-12 (9th Cir. Feb. 7, 2019).
Extreme weather events, such as intense rainfall events that
cause flooding, are increasing in frequency and severity
because a warmer atmosphere holds more moisture.\25\ What are
supposedly 1-in-1,000-year rainfall events are now occurring
with alarming frequency--in 2018 there were at least five such
events.\26\
---------------------------------------------------------------------------
\25\ Kevin E. Trenberth, Declaration in Support of Plaintiffs,
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-3-Trenberth-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf),
No. 18-36082, Doc. 21-3 (9th Cir. Feb. 7, 2019).
\26\ Belles, F., America's `One-in-1,000-Year' Rainfall Events in
2018, The Weather Channel (Sept. 27, 2018).
Tropical storms and hurricanes are increasing in intensity,
both in terms of rainfall and windspeed, as warmer oceans
provide more energy for the storms (we saw this with Hurricanes
Harvey, Irma, and Maria in 2017) (Figure 7).\27\
---------------------------------------------------------------------------
\27\ Kevin E. Trenberth, Declaration in Support of Plaintiffs,
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-3-Trenberth-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf),
No. 18-36082, Doc. 21-3 (9th Cir. Feb. 7, 2019).
---------------------------------------------------------------------------
Figure 7
Flooding in Port Arthur, Texas on August 13, 2018 after
Hurricane Harvey.
Terrestrial ecosystems are experiencing compositional and
structural changes, with major adverse consequences for
ecosystem services.\28\
---------------------------------------------------------------------------
\28\ Nolan, et al., Past and future global transformation of
terrestrial ecosystems under climate change, Science (2018).
Terrestrial, freshwater, and marine species are experiencing
a significant decrease in population size and geographic range,
with some going extinct and others are facing the very real
prospect of extinction--the rapid rate of extinctions has been
called the 6th mass extinction.\29\
---------------------------------------------------------------------------
\29\ G. Ceballos, et al., Accelerated modern human-induced species
losses: Entering the sixth mass extinction, Science Advances (2015);
Steven W. Running, Expert Report, Juliana v. United States (https://
www.ourchildrenstrust.org/s/Doc-264-1-Running-Expert-Report.pdf), No.
6:15-cv-01517-TC, Doc. 264-1 (D. Or. June 28, 2018).
Human health and well-being are already being affected by
heat waves, floods, droughts, and extreme events; infectious
diseases; quality of air, food, and water.\30\ Doctors and
leading medical institutions are calling climate change a
``health emergency.'' \31\ Children are being uniquely impacted
by climate change.\32\
---------------------------------------------------------------------------
\30\ Ebi, K. L., et al., Human Health. In Impacts, Risks, and
Adaptation in the United States: Fourth National Climate Assessment,
Volume II, USGCRP (2018).
\31\ Solomon, C.G. & LaRocque R.C., Climate Change--A Health
Emergency, N. Engl. J. Med. 380:3 (2019).
\32\ May, C., et al., Northwest. In Impacts, Risks, and Adaptation
in the United States: Fourth National Climate Assessment, Volume II,
USGCRP (2018); Watts, N., et al., The 2018 report of the Lancet
Countdown on health and climate change: shaping the health of nations
for centuries to come, Lancet, Vol. 392 at 2482 (2018); Brief of Amici
Curiae Public Health Experts, Public Health Organizations, and Doctors
in Support of Plaintiffs (https://www.ourchildrenstrust.org/s/DktEntry-
47-Amicus-of-Public-Health-Experts-ISO-Pls.pdf), No. 18-36082, Doc. 47
(9th Cir. Mar. 1, 2019).
In addition to physical harm, climate change is causing
mental health impacts, ranging from stress to suicide, due to
exposure to climate impacts, displacement, loss of income,
chronic stress, and other impacts of climate change.\33\
---------------------------------------------------------------------------
\33\ Lise Van Susteren, Expert Report, Juliana v. United States
(https://www.ourchildrenstrust.org/s/Doc-271-1-Van-Susteren-Expert-
Report.pdf), No. 6:15-cv-01517-TC, Doc. 271-1 (D. Or. June 28, 2018).
As Congress has recognized, ``climate change is a direct
threat to the national security of the United States and is
impacting stability in areas of the world both where the United
States Armed Forces are operating today, and where strategic
implications for future conflict exist.'' \34\ Senior military
leaders have called climate change ``the most serious national
security threat facing our Nation today,'' \35\ a conclusion
similarly recognized by our nation's intelligence
community.\36\ Climate change is increasing food and water
shortages, pandemic disease, conflicts over refugees and
resources, and destruction to homes, land, infrastructure, and
military assets, directly threatening our military personnel
and the ``Department of Defense's ability to defend the
Nation'' (see Figure 8).\37\
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\34\ National Defense Authorization Act for Fiscal Year 2018, Pub.
L. No. 115-91, 131 Stat. 1358.
\35\ Vice Admiral Lee Gunn, USN (Ret.), Declaration in Support of
Plaintiffs, Juliana v. United States (https://
www.ourchildrenstrust.org/s/DktEntry-21-17-Gunn-Dec-ISO-Urgent-Motion-
for-Preliminary-Injunction.pdf), No. 18-36082, Doc. 21-17 (9th Cir.
Feb. 7, 2019) (emphasis in original); see also CNA Military Advisory
Board, National Security and the Accelerating Risks of Climate Change
(2014), https://www.cna.org/cna_files/pdf/MAB_5-8-14.pdf.
\36\ National Intelligence Council, Implications for U.S. National
Security of Anticipated Climate Change (Sept. 2016), https://
www.dni.gov/files/documents/Newsroom/Reports and Pubs/
Implications_for_US_National_Security_of_Anticipated_Climate_Change.pdf.
\37\ U.S. Dep't of Defense, 2014 Climate Change Adaptation Roadmap
(2014), https://www.acq.osd.mil/eie/downloads/CCARprint_wForward_e.pdf.
---------------------------------------------------------------------------
Figure 8
Offutt Air Force Base was impacted by flood waters during
flooding in Nebraska during spring 2019.
Climate change is already causing vast economic harm in the
United States. Since 1980 the United States has experienced 246
climate and weather disasters that each caused damages in
excess of $1 billion, for a total cost of $1.6 trillion.\38\ In
2018 alone, Congress appropriated more than $130 billion for
weather and climate related disasters.\39\
---------------------------------------------------------------------------
\38\ NOAA, Billion Dollar U.S. Weather/Climate Disasters 1980-2019
(2019), http://www.ncdc.noaa.gov/billions/events.pdf.
\39\ U.S. House of Representatives Committee on the Budget, The
Budgetary Impact of Climate Change 2 (Nov. 27, 2018).
These already serious impacts will grow in severity and will impact
increasingly large numbers of people and parts of the world if
CO2 concentrations continue to rise. If we want our children
and grandchildren to have a safe planet to live on, full of health and
biodiversity rather than chaos and conflict, we must follow the best
scientific prescription to restore Earth's energy balance and avoid the
destruction of our planet's atmosphere, climate, and oceans.
International Political Targets of 1.5 C Or 2 C Are Not Science-Based
and Are Not Safe
International, politically-recognized targets like 1.5 C or ``well
below'' 2 C--which are commonlyassociated with long-term atmospheric
CO2 concentrations of 425 and 450 ppm, respectively--have
not been and are not presently considered safe or scientifically-sound
targets for present or future generations.
Importantly, the Intergovernmental Panel on Climate Change
(``IPCC'') has never established nor endorsed a target of 1.5 C or 2
C warming as a limit below which the climate system will be
stable.\40\ It is beyond the IPCC's declared mandate to endorse a
particular threshold of warming as ``safe'' or ``dangerous.'' As the
IPCC makes clear, ``each major IPCC assessment has examined the impacts
of [a] multiplicity of temperature changes but has left [it to the]
political processes to make decisions on which thresholds may be
appropriate.'' \41\
---------------------------------------------------------------------------
\40\ Dec. of Dr. James E. Hansen, Juliana, et al., v. United
States, et al., No. 6:15-cv-01517-TC, 5 (D. Or. Aug. 12, 2015).
\41\ IPCC, Climate Change 2014: Mitigation of Climate Change,
Contribution of Working Group III to the Fifth Assessment Report, 125
(2014), http://report.mitigation2014.org/report/
ipcc_wg3_ar5_chapter1.pdf.
---------------------------------------------------------------------------
Neither 1.5 C nor 2 C warming above pre-industrial levels has
ever been considered ``safe'' from either a political or scientific
point of view. The
2 C figure was originally adopted in the political arena ``from a set
of heuristics,'' and it has retained predominantly political character
ever since.\42\ It has recently been all-but-abandoned as a credible
policy goal, in light of the findings in IPCC's 1.5 C Special Report,
and the mounting evidence leading up to its publication, that 2 C
would be catastrophic relative to lower, still-achievable levels of
warming.\43\
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\42\ Randalls, S. History of the 2 C Temperature Target. 1. WIREs
Climate Change 598, 603 (2010); Jaeger, C. and J. Jaeger, Three views
of two degrees. 11 (Suppl. 1) Regional Environmental Change S15 (2011).
\43\ IPCC, Summary for policymakers at 13-14, Climate Change 2014:
Impacts, Adaptation, and Vulnerability (2014), http://www.ipcc.ch/pdf/
assessment-report/ar5/wg2/ar5_wgII_spm_en.
pdf; UNFCCC, Report on the structured expert dialogue on the 2013-2015
review, 18 (2015), http://unfccc.int/resource/docs/2015/sb/eng/
inf01.pdf; Petra Tschakert, 1.5 C or 2 C: a conduit's view from the
science-policy interface at COP20 in Lima, Peru, Climate Change
Responses 8 (2015), http://www.climatechangeresponses.com/content/2/1/
3; IPCC, Global warming of 1.5 C: An IPCC Special Report on the
impacts of global warming of 1.5 C above pre-industrial levels and
related global greenhouse gas emission pathways, in the context of
strengthening the global response to the threat of climate change,
sustainable development, and efforts to eradicate poverty (2018),
https://www.ipcc.ch/sr15/.
---------------------------------------------------------------------------
On the other hand, the idea of a 1.5 C target was first raised by
the Association of Small Island States (AOSIS) in the negotiations
leading up to the ill-fated 2009 UNFCCC Conference of Parties in
Copenhagen.\44\ AOSIS, however, was explicitly advocating a well below
1.5 C and well below 1 C target, on the basis of the research of Dr.
James Hansen and his colleagues.\45\ Political compromise on this
science-based target then led to the adoption of a goal of ``pursuing
efforts to limit the temperature increase to 1.5 C above pre-
industrial levels'' in Article 2 of the Paris Agreement. Yet the 2018
IPCC Special Report on 1.5 C has made clear that allowing a
temperature rise of 1.5 C:
---------------------------------------------------------------------------
\44\ See Webster, R. A brief history of the 1.5C target. Climate
Change News (December 10, 2015), http://www.climatechangenews.com/2015/
12/10/a-brief-history-of-the-1-5c-target/; Submission from Grenada on
behalf of AOISIS to the Ad Hoc Working Group on Further Commitments for
Annex I Parties Under the Kyoto Protocol, U.N. Doc. FCCC/KP/AWG/2009/
MISC.1/Add.1 (25 March 2009), https://unfccc.int/sites/default/files/
resource/docs/2009/awg7/eng/misc01a01.pdf.
\45\ Submission from Grenada on behalf of AOISIS to the Ad Hoc
Working Group on Further Commitments for Annex I Parties Under the
Kyoto Protocol, U.N. Doc. FCCC/KP/AWG/2009/MISC.1/Add.1 (25 March
2009), https://unfccc.int/sites/default/files/resource/docs/2009/awg7/
eng/misc01a01.pdf, citing Hansen, J., et al., Target Atmospheric
CO2: Where Should Humanity Aim? 2 The Open Atmospheric
Science Journal 217 (2008).
is not considered `safe' for most nations, communities,
ecosystems, and sectors and poses significant risks to natural
and human systems as compared to current warming of 1 C (high
confidence) . . . .\46\
---------------------------------------------------------------------------
\46\ Roy, J., et al., Sustainable Development, Poverty Eradication
and Reducing Inequalities. In Global Warming of 1.5C. An IPCC Special
Report on the impacts of global warming of 1.5C above pre-industrial
levels and related global greenhouse gas emission pathways, in the
context of strengthening the global response to the threat of climate
change, sustainable development, and efforts to eradicate poverty at
447 (2018) (emphasis added)
Dr. James Hansen warns that ``distinctions between pathways aimed
at 1 C and 2 C warming are much greater and more fundamental than the
numbers 1 C and 2 C themselves might suggest. These fundamental
distinctions make scenarios with 2 C or more global warming far more
dangerous; so dangerous, we [James Hansen, et al.] suggest, that aiming
for the 2 C pathway would be foolhardy.'' \47\ This target is at best
the equivalent of ``flip[ping] a coin in the hopes that future
generations are not left with few choices beyond mere survival. This is
not risk management, it is recklessness and we must do better.'' \48\
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\47\ Id. at 15.
\48\ Matt Vespa, Why 350? Climate Policy Must Aim to Stabilize
Greenhouse Gases at the Level Necessary to Minimize the Risk of
Catastrophic Outcomes, 36 Ecology Law Currents 185, 186 (2009), http://
www.biologicaldiversity.org/publications/papers/Why_350.pdf.
---------------------------------------------------------------------------
Tellingly, more than 45 eminent scientists from over 40 different
institutions have published in peer-reviewed journals finding that the
maximum level of atmospheric CO2 consistent with protecting
humanity and other species is 350 ppm, and no one, including the IPCC,
has published any scientific evidence to counter that 350 is the
maximum safe concentration of CO2.\49\
---------------------------------------------------------------------------
\49\ James Hansen, et al., Target Atmospheric CO2: Where
Should Humanity Aim? (2008); James Hansen, et al., Assessing
``Dangerous Climate Change'': Required Reduction of Carbon Emissions to
Protect Young People, Future Generations and Nature (2013); James
Hansen, et al., Ice Melt, Sea Level Rise and Superstorms: Evidence From
Paleoclimate Data, Climate Modeling, and Modern Observations That 2 C
Global Warming Could Be Dangerous (2016); James Hansen, et al., Young
People's Burden: Requirement of Negative CO2 Emissions
(2017); Veron, J., et al., The Coral Reef Crisis: The Critical
Importance of <350 ppm CO2 (2009); Frieler, K., et al.,
Limiting global warming to 2 C is unlikely to save most coral reefs
(2012).
---------------------------------------------------------------------------
A 1.5 Or 2 C Target Risks Locking-In Dangerous Feedbacks
The longer the length of time atmospheric CO2
concentrations remain at dangerous levels (i.e., above 350 ppm) and
there is an energy imbalance in the atmosphere, the risk of triggering,
and locking-in, dangerous warming-driven feedback loops increases. The
1.5 C or 2 C target reduces the likelihood that the biosphere will be
able to sequester CO2 due to carbon cycle feedbacks and
shifting climate zones.\50\ As temperatures warm, forests burn and
soils warm, releasing their carbon. These natural carbon ``sinks''
become carbon ``sources'' and a portion of the natural carbon
sequestration necessary to drawdown excess CO2 simply
disappear. Another dangerous feedback includes the release of methane,
a potent greenhouse gas, as the global tundra thaws.\51\ These
feedbacks might show little change in the short-term, but can hit a
point of no return, even at a 1.5 C or 2 C temperature increase,
which will trigger accelerated heating and sudden and irreversible
catastrophic impacts. Moreover, an emission reduction target aimed at 2
C would ``yield a larger eventual warming because of slow feedbacks,
probably at least 3 C.'' \52\ Once a temperature increase of 2 C is
reached, there will already be ``additional climate change `in the
pipeline' even without further change of atmospheric composition.''
\53\
---------------------------------------------------------------------------
\50\ Id. at 15, 20.
\51\ Id.
\52\ Hansen, Assessing ``Dangerous Climate Change,'' at 15.
\53\ Id. at 19.
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It Is Technologically and Economically Feasible To Reduce
CO2 Levels to 350 ppm by 2100
There are two steps to reducing CO2 levels to 350 ppm by
the end of the century: (1) reducing CO2 emissions; and (2)
sequestering excess CO2 already in the atmosphere. Carbon
dioxide emission reductions of approximately 80% by 2030 and close to
100% by 2050 (in addition to the requisite CO2
sequestration) are necessary to keep long-term warming to 1 C and the
atmospheric CO2 concentration to 350 ppm. Emission reduction
targets that seek to reduce CO2 emissions by 80% by 2050 are
consistent with long-term warming of 2 C and an atmospheric
CO2 concentration of 450 ppm, which, as described above,
would result in catastrophic and irreversible impacts for the climate
system and oceans. Importantly, it is economically and technologically
feasible to transition the entire U.S. energy system to a zero-
CO2 energy system by 2050 and to drawdown the excess
CO2 in the atmosphere through reforestation and carbon
sequestration in soils.\54\
---------------------------------------------------------------------------
\54\ See Mark Z. Jacobson, et al., 100% Clean and Renewable Wind,
Water, and Sunlight (WWS) All-Sector Energy Roadmaps for the 50 United
States, 8 Energy & Envtl. Sci. 2093 (2015) (for plans on how the United
States and over 100 other countries can transition to a 100% renewable
energy economy see www.thesolutionsproject.org); see also Arjun
Makhijani, Carbon-Free, Nuclear-Free: A Roadmap for U.S. Energy Policy
(2007); B. Haley, et al., 350 ppm pathways for the United States
(2019).
---------------------------------------------------------------------------
Deep Decarbonization Pathways Project and Evolved Energy Research
recently completed research and very sophisticated modeling describing
a nearly complete phase out of fossil fuels in the U.S. by 2050.\55\
They describe six different technologically feasible pathways to
drastically, and quickly, cut our reliance on fossil fuels and achieve
the requisite level of emissions reductions in the U.S. while meeting
our nation's forecasted energy needs. All of the 350 ppm pathways rely
on four pillars of action: (a) investment in energy efficiency; (b)
electrification of everything that can be electrified; (c) shifting to
very low-carbon and primarily renewable electricity generation; and (d)
carbon dioxide capture as fossil fuels are phased out. The six
scenarios are used to evaluate the ability to meet the targets even
absent one key technology. For example, one scenario describes a route
to 350 absent construction of new nuclear facilities; another
illustrates getting to 350 with extremely limited biomass technology;
still another describes a way to 350 without any carbon capture and
storage. Even absent a key technology, each of these six routes are
viable and cost effective.
---------------------------------------------------------------------------
\55\ B. Haley, et al., 350 ppm pathways for the United States
(2019).
---------------------------------------------------------------------------
The study also concludes that the cost of the energy system
transition is affordable. The total cost of supplying and using energy
in the U.S. in 2016 was about 5.6% of GDP (see Figure 9).\56\ A
transition from fossil fuels to low carbon energy sources is expected
to increase those costs by no more than an additional two to three
percent of GDP. Even with this small and temporary added expense, the
cost would still be well below the 9.5% of GDP spent on the energy
system in 2009 (not to mention well below the harm to the economy
caused by climate change). Once the transition is complete, the cost of
energy will remain low and stable because we will no longer be
dependent on volatile global fossil fuel markets for our energy
supplies. As Nobel Laureate Economist Dr. Joseph Stiglitz has stated:
``[t]he benefits of making choices today that limit the economic costs
of climate change far outweigh any economic costs associated with
limiting our use of fossil fuels.'' \57\
---------------------------------------------------------------------------
\56\ B. Haley, et al., 350 ppm pathways for the United States
(2019).
\57\ Joseph E. Stiglitz, Ph.D., Declaration in Support of
Plaintiffs, Juliana v. United States (https://
www.ourchildrenstrust.org/s/DktEntry-21-14-Stiglitz-Dec-ISO-Urgent-
Motion-for-Preliminary-Injunction.pdf), No. 18-36082, Doc. 21-14 (9th
Cir. Feb. 7, 2019).
---------------------------------------------------------------------------
Figure 9
Historic and Projected Costs of Energy in the U.S.
Other experts have already prepared plans for all 50 U.S. states as
well as for over 139 countries that demonstrate the technological and
economic feasibility of transitioning off of fossil fuels toward 100%
of energy, for all energy sectors, from clean and renewable energy
sources: wind, water, and sunlight by 2050 (with 80% reductions in
fossil fuels by 2030).\58\
---------------------------------------------------------------------------
\58\ Mark Z. Jacobson, et al., 100% Clean and Renewable Wind,
Water, and Sunlight (WWS) All-Sector Energy Roadmaps for the 50 United
States, 8 Energy & Envtl. Sci. 2093 (2015). For a graphic depicting the
overview of the plan for the United States see: https://
thesolutionsproject.org/why-clean-energy/#/map/countries/location/USA.
---------------------------------------------------------------------------
Products already exist that enable new construction or retrofits
that result in zero greenhouse gas buildings. We have the technology to
meet all electricity needs with zero-emission electric generation. We
know how to achieve zero-emission transportation, including aviation.
These actions result in other benefits, such as improved health, job
creation, and savings on energy costs.
The amount of natural carbon sequestration required is also proven
to be feasible. Researchers have evaluated the potential to drawdown
excess carbon dioxide in the atmosphere by increasing the carbon stored
in forests, soils, and wetlands, and have found significant potential
for these natural systems to support a return to 350 ppm by the end of
the century.\59\ We know the agricultural, rangeland, wetland, and
forest management practices that decrease greenhouse gas emissions and
increase sequestration.
---------------------------------------------------------------------------
\59\ Benson W. Griscom, et al., Natural Climate Solutions,
Proceedings of the National Academies of Sciences (2017); Joseph E.
Fargione, et al., Natural Climate Solutions for the United States,
Science Advances (2018).
---------------------------------------------------------------------------
There is no scientific, technological, or economic reason to not
adopt a 350 ppm and 1 C by 2100 target. There are abundant reasons for
doing so, not the least of which is to do our best through human laws
to respect the laws of nature and create a safe and healthy world for
children and future generations who will walk this Earth.
Exhibit E.1: 350 PPM Pathways for the United States (2019), Executive
Summary, Evolved Energy Research
May 8, 2019
Prepared by Ben Haley, Ryan Jones, Gabe Kwok, Jeremy Hargreaves &
Jamil Farbes, Evolved Energy Research
James H. Williams, University of San Francisco, Sustainable
Development Solutions Network
Executive Summary
This report describes the changes in the U.S. energy system
required to reduce carbon dioxide (CO2) emissions to a level
consistent with returning atmospheric concentrations to 350 parts per
million (350 ppm) in 2100, achieving net negative CO2
emissions by mid-century, and limiting end-of-century global warming to
1 C above pre-industrial levels. The main finding is that 350 ppm
pathways that meet all current and forecast U.S. energy needs are
technically feasible using existing technology, and that multiple
alternative pathways can meet these objectives in the case of limits on
some key decarbonization strategies. These pathways are economically
viable, with a net increase in the cost of supplying and using energy
equivalent to about 2% of GDP, up to a maximum of 3% of GDP, relative
to the cost of a business-as-usual baseline. These figures are for
energy costs only and do not count the economic benefits of avoided
climate change and other energy-related environmental and public health
impacts, which have been described elsewhere.\1\
---------------------------------------------------------------------------
\1\ See e.g., Risky Business: The Bottom Line on Climate Change,
available at https://riskybusiness.org/.
---------------------------------------------------------------------------
This study builds on previous work, Pathways to Deep
Decarbonization in the United States (2014) and Policy Implications of
Deep Decarbonization in the United States (2015), which examined the
requirements for reducing GHG emissions by 80% below 1990 levels by
2050 (``80 x 50'').\2\ These studies found that an 80% reduction by
mid-century is technically feasible and economically affordable, and
attainable using different technological approaches. The main
requirement of the transition is the construction of a low carbon
infrastructure characterized by high energy efficiency, low-carbon
electricity, and replacement of fossil fuel combustion with
decarbonized electricity and other fuels, along with the policies
needed to achieve this transformation. The findings of the present
study are similar but reflect both a more stringent emissions limit and
the consequences of 5 intervening years without aggressive emissions
reductions in the U.S. or globally.
---------------------------------------------------------------------------
\2\ Available at http://usddpp.org/.
---------------------------------------------------------------------------
The 80 x 50 analysis was developed in concert with similar studies
for other high-emitting countries by the country research teams of the
Deep Decarbonization Pathways Project, with an agreed objective of
limiting global warming to 2 C above pre-industrial levels.\3\
However, new studies of climate change have led to a growing consensus
that even a 2 C increase may be too high to avoid dangerous impacts.
Some scientists assert that staying well below 1.5 C, with a return to
1 C or less by the end of the century, will be necessary to avoid
irreversible feedbacks to the climate system.\4\ A recent report by the
IPCC indicates that keeping warming below 1.5 C will likely require
reaching net-zero emissions of CO2 globally by mid-century
or earlier.\5\ A number of jurisdictions around the world have
accordingly announced more aggressive emissions targets, for example
California's recent executive order calling for the state to achieve
carbon neutrality by 2045 and net negative emissions thereafter.\6\
---------------------------------------------------------------------------
\3\ Available at http://deepdecarbonization.org/countries/.
\4\ James Hansen, et al., (2017) ``Young people's burden:
requirement of negative CO2 emissions,'' Earth System
Dynamics, https://www.earth-syst-dynam.net/8/577/2017/esd-8-577-
2017.html.
\5\ Available at https://www.ipcc.ch/sr15/.
\6\ Available at https://www.gov.ca.gov/wp-content/uploads/2018/09/
9.10.18-Executive-Order.pdf.
---------------------------------------------------------------------------
In this study we have modeled the pathways--the sequence of
technology and infrastructure changes--consistent with net negative
CO2 emissions before mid-century and with keeping peak
warming below 1.5 C. We model these pathways for the U.S. for each
year from 2020 to 2050, following a global emissions trajectory that
would return atmospheric CO2 to 350 ppm by 2100, causing
warming to peak well below 1.5 C and not exceed 1.0 C by century's
end.\7\ The cases modeled are a 6% per year and a 12% per year
reduction in net fossil fuel CO2 emissions after 2020. These
equate to a cumulative emissions limit for the U.S. during the 2020 to
2050 period of 74 billion metric tons of CO2 in the 6% case
and 47 billion metric tons in the 12% case. (For comparison, current
U.S. CO2 emissions are about 5 billion metric tons per
year.) The emissions in both cases must be accompanied by increased
extraction of CO2 from the atmosphere using land-based
negative emissions technologies (``land NETs''), such as reforestation,
with greater extraction required in the 6% case.
---------------------------------------------------------------------------
\7\ Hansen, et al., (2017).
---------------------------------------------------------------------------
Figure ES1
Global surface temperature and CO2 emissions
trajectories. Hansen, et al., 2017.
We studied six different scenarios: five that follow the 6% per
year reduction path and one that follows the 12% path. All reach net
negative CO2 by mid-century while providing the same energy
services for daily life and industrial production as the Annual Energy
Outlook (AEO), the Department of Energy's long-term forecast. The
scenarios explore the effects of limits on key decarbonization
strategies: bioenergy, nuclear power, electrification, land NETs, and
technological negative emissions technologies (``tech NETs''), such as
carbon capture and storage (CCS) and direct air capture (DAC).
Table ES1. Scenarios Developed in this Study
----------------------------------------------------------------------------------------------------------------
Year 2050 maximum
Average annual rate 2020-2050 maximum Year 2050 maximum net CO2 with 50%
Scenario of CO2 emission cumulative fossil net fossil fuel CO2 increase in land
reduction fuel CO2 (million (million metric sink (million metric
metric tons) tons) tons)
----------------------------------------------------------------------------------------------------------------
Base 6% 73,900 830 ^250
Low Biomass 6% 73,900 830 ^250
Low Electrification 6% 73,900 830 ^250
No New Nuclear 6% 73,900 830 ^250
No Tech NETS 6% 73,900 830 ^250
Low Land NETS 12% 57,000 ^200 ^450
----------------------------------------------------------------------------------------------------------------
The scenarios were modeled using two new analysis tools developed
for this purpose, EnergyPATHWAYS and RIO. As extensively described in
the Appendix,* these are sophisticated models with a high level of
sectoral, temporal, and geographic detail, which ensure that the
scenarios account for such things as the inertia of infrastructure
stocks and the hour-to-hour dynamics of the electricity system,
separately in each of fourteen electric grid regions of the U.S. The
changes in energy mix, emissions, and costs for the six scenarios were
calculated relative to a high-carbon baseline also drawn from the AEO.
---------------------------------------------------------------------------
* Editor's note: the Our Children's Trust submission for the record
for this hearing does not include Appendix. It has been reproduced, as
submitted, herein. The full report (which includes the Appendix) is
retained in Committee file and is available at: https://
docs.wixstatic.com/ugd/294abc_95dfdf602afe4e11a184ee65ba565e60.pdf.
---------------------------------------------------------------------------
Relative to 80 x 50 trajectories, a 350 ppm trajectory that
achieves net negative CO2 by midcentury requires more rapid
decarbonization of energy plus more rapid removal of CO2
from the atmosphere. For this analysis, an enhanced land sink 50%
larger than the current annual sink of approximately 700 million metric
tons was assumed.\8\ This would require additional sequestration of 25-
30 billion metric tons of CO2 from 2020 to 2100. The present
study does not address the cost or technical feasibility of this
assumption but stipulates it as a plausible value for calculating an
overall CO2 budget, based on consideration of the scientific
literature in this area.\9\
---------------------------------------------------------------------------
\8\ U.S. EPA, Inventory of U.S. Greenhouse Gas Emissions and Sinks
1990-2016, available at https://www.epa.gov/ghgemissions/inventory-us-
greenhouse-gas-emissions-and-sinks-1990-2016.
\9\ Griscom, Bronson W., et al., (2017) ``Natural climate
solutions.'' Proceedings of the National Academy of Sciences 114.44
(2017): 11645-11650; Fargione, Joseph E., et al., (2018) ``Natural
climate solutions for the United States.'' Science Advances 4.11:
eaat1869.
---------------------------------------------------------------------------
Figure ES2
Four pillars of deep decarbonization--Base case.
Energy decarbonization rests on the four principal strategies
(``four pillars'') shown in Figure ES2: (1) electricity
decarbonization, the reduction in emissions intensity of electricity
generation by about 90% below today's level by 2050; (2) energy
efficiency, the reduction in energy required to provide energy services
such as heating and transportation, by about 60% below today's level;
(3) electrification, converting end-uses like transportation and
heating from fossils fuels to low-carbon electricity, so that
electricity triples its share from 20% of current end uses to 60% in
2050; and (4) carbon capture, the capture of otherwise CO2
that would otherwise be emitted from power plants and industrial
facilities, plus direct air capture, rising from nearly zero today to
as much as 800 million metric tons in 2050 in some scenarios. The
captured carbon may be sequestered or may be utilized in making
synthetic renewable fuels.
Achieving this transformation by mid-century requires an aggressive
deployment of low-carbon technologies. Key actions include retiring all
existing coal power generation, approximately doubling electricity
generation primarily with solar and wind power and electrifying
virtually all passenger vehicles and natural gas uses in buildings. It
also includes creating new types of infrastructure, namely large-scale
industrial facilities for carbon capture and storage, direct air
capture of CO2, the production of gaseous and liquid
biofuels with zero net lifecycle CO2, and the production of
hydrogen from water electrolysis using excess renewable electricity.
The scale of the infrastructure buildout by region is indicated in
Figure ES3.
Figure ES3
Regional infrastructure requirements (Low Land NETS
scenario).
Figure ES4 shows that all scenarios achieve the steep reductions in
net fossil fuel CO2 emissions to reach net negative
emissions by the 2040s, given a 50% increase in the land sink,
including five that are limited in one key area. This indicates that
the feasibility of reaching the emissions goals is robust due to the
ability to substitute strategies. At same time, the more limited
scenarios are, the more difficult and/or costly they are relative to
the base case with all options available. Severe limits in two or more
areas were not studied here but would make the emissions goals more
difficult to achieve in the mid-century time frame.
Figure ES4
2020-2050 CO2 emissions for the scenarios in this
study.
Figure ES5 shows U.S. energy system costs as a share of GDP for the
baseline case and six 350 ppm scenarios in comparison to historical
energy system costs. While the 350 ppm scenarios have a net cost of 2-
3% of GDP more than the business as usual baseline, these costs are not
out of line with historical energy costs in the U.S. The highest cost
case is the Low Land NETs scenario, which requires a 12% per year
reduction in net fossil fuel CO2 emissions. By comparison,
the 6% per year reduction cases are more closely clustered. The lowest
increase is the Base scenario, which incorporates all the key
decarbonization strategies. These costs do not include any potential
economic benefits of avoided climate change or pollution, which could
equal or exceed the net costs shown here.
Figure ES5
Total energy system costs as percentage of GDP, modeled (R.)
and historical (L.).
A key finding of this study is the potentially important future
role of ``the circular carbon economy.'' This refers to the economic
complementarity of hydrogen production, direct air capture of
CO2, and fuel synthesis, in combination with an electricity
system with very high levels of intermittent renewable generation. If
these facilities operate flexibly to take advantage of periods of
excess generation, the production of hydrogen and CO2
feedstocks can provide an economic use for otherwise curtailed energy
that is difficult to utilize with electric energy storage technologies
of limited duration. These hydrogen and CO2 feedstocks can
be combined as alternatives for gaseous and liquid fuel end-uses that
are difficult to electrify directly like freight applications and air
travel. While the CO2 is eventually emitted to the
atmosphere, the overall process is carbon neutral as it was extracted
from the air and not emitted from fossil reserves. A related finding of
this work is that bioenergy with carbon capture and storage (BECCS) for
power plants appears uneconomic, while BECCS for bio-refineries appears
highly economic and can be used as an alternative source of
CO2 feedstocks in a low-carbon economy.
There are several areas outside the scope of this study that are
important to provide a full picture of a low greenhouse gas transition.
One important area is better understanding of the potential and cost of
land-based NETs, both globally and in the U.S. Another is the potential
and cost of reductions in non-CO2 climate pollutants such as
methane, nitrous oxide, and black carbon. Finally, there is the
question of the prospects for significant reductions in energy service
demand, due to lifestyle choices such as bicycling over cars,
structural changes such as increased transit and use of ride-sharing,
or the development of less-energy intensive industry, perhaps based on
new types of materials.
``Key Actions by Decade'' below provides a blueprint for the
physical transformation of the energy system. From a policy
perspective, this provides a list of the things that policy needs to
accomplish, for example the deployment of large amounts of low carbon
generation, rapid electrification of vehicles, buildings, and industry,
and building extensive carbon capture, biofuel, hydrogen, and synthetic
fuel synthesis capacity.
Some of the policy challenges that must be managed include: land
use tradeoffs related to carbon storage in ecosystems and siting of low
carbon generation and transmission; electricity market designs that
maintain natural gas generation capacity for reliability while running
it very infrequently; electricity market designs that reward demand
side flexibility in high-renewables electricity system and encourage
the development of complementary carbon capture and fuel synthesis
industries; coordination of planning and policy across sectors that
previously had little interaction but will require much more in a low
carbon future, such as transportation and electricity; coordination of
planning and policy across jurisdictions, both vertically from local to
state to Federal levels, and horizontally across neighbors and trading
partners at the same level; mobilizing investment for a rapid low
carbon transition, while ensuring that new investments in long-lived
infrastructure are made with full awareness of what they imply for
long-term carbon commitment; and investing in ongoing modeling,
analysis, and data collection that informs both public and private
decision-making. These topics are discussed in more detail in Policy
Implications of Deep Decarbonization in the United States.
Key Actions by Decade
This study identifies key actions that are required in each decade
from now to mid-century in order to achieve net negative CO2
emissions by mid-century, at least cost, while delivering the energy
services projected in the Annual Energy Outlook. Such a list inherently
relies on current knowledge and forecasts of unknowable future costs,
capabilities, and events, yet a long-term blueprint remains essential
because of the long lifetimes of infrastructure in the energy system
and the carbon consequences of investment decisions made today. As
events unfold, technology improves, energy service projections change,
and understanding of climate science evolves, energy system analysis
and blueprints of this type must be frequently updated.
2020s
Begin large-scale electrification in transportation and
buildings.
Switch from coal to gas in electricity system dispatch.
Ramp up construction of renewable generation and reinforce
transmission.
Allow new natural gas power plants to be built to replace
retiring plants.
Start electricity market reforms to prepare for a changing
load and resource mix.
Maintain existing nuclear fleet.
Pilot new technologies that will need to be deployed at
scale after 2030.
Stop developing new infrastructure to transport fossil
fuels.
Begin building carbon capture for large industrial
facilities.
2030s
Maximum build-out of renewable generation.
Attain near 100% sales share for key electrified
technologies (e.g., EVs).
Begin large-scale production of biodiesel and bio-jet fuel.
Large scale carbon capture on industrial facilities.
Build out of electrical energy storage.
Deploy fossil power plants capable of 100% carbon capture if
they exist.
[] Maintain existing nuclear fleet.
2040s
Complete electrification process for key technologies,
achieve 100% stock penetration.
Deploy circular carbon economy using DAC and hydrogen to
produce synthetic fuels.
Use synthetic fuel production to balance and expand
renewable generation.
Replace nuclear at the end of existing plant lifetime with
new generation technologies.
Fully deploy biofuel production with carbon capture.
Exhibit E.2: 350 PPM Pathways for Florida (2020), Executive Summary and
U.S. data from the Technical Supplement, Evolved Energy
Research
October 6, 2020
Prepared by Ben Haley, Gabe Kwok, and Ryan Jones, Evolved Energy
Research
Executive Summary
This study evaluates multiple scenarios to radically reduce the
greenhouse gas emissions that result from Florida's energy system, and
can serve as a tool to inform statewide energy system decisions.
We detail five technically and economically feasible pathways to
reduce carbon dioxide emissions and remain within a small enough
``carbon budget'' to enable a return to 350 parts per million of carbon
dioxide in the atmosphere by 2100, a level identified by scientists as
a safe limit necessary to preserve a stable climate. These scenarios
limit emissions while providing the same energy services for daily life
and industrial production as the Department of Energy's long-term
forecast.
This study builds upon the research conducted by Evolved Energy
Research and the Sustainability Development Solutions Network (SDSN)
and published on May 8, 2019, titled 350 PPM Pathways for the United
States.
Scenarios
This study evaluates five energy decarbonization \1\ scenarios for
the energy system of Florida:
---------------------------------------------------------------------------
\1\ ``Decarbonization'' is the process of removing sources of
carbon dioxide (and other greenhouse gases) from a system--in this
case, removing fossil fuel emissions from Florida's energy system.
---------------------------------------------------------------------------
Central: The least constrained scenario, this uses all options to
decarbonize the energy system.
Low Biomass: This scenario reduces the development of new biomass
feedstocks \2\ by 50%.
---------------------------------------------------------------------------
\2\ Biomass feedstocks are plant-based and animal-based sources of
fuel, like trees, grasses, or animal fats, for example.
---------------------------------------------------------------------------
Low Electrification: This scenario assesses the impact of a delayed
adoption of electric vehicles and heat pumps.
100% Renewable Primary: This scenario describes an energy system
based solely on biomass, wind, solar, hydro, and geothermal sources by
2050.
No New Regional Transmission (TX): This scenario limits the
development of new electricity transmission lines between regions
within the U.S.
Florida Energy System Results
Energy decarbonization in Florida relies on four principal
strategies: (1) Electricity decarbonization requires reducing the
amount of fossil fuels used for electricity generation, thereby
reducing the amount of greenhouse gas emissions from every unit of
electricity delivered by about 95% by 2050; (2) Energy efficiency is
the reduction in energy required to provide energy services such as
heating and transportation, and energy use per unit GDP is reduced by
about 50% below today's level; (3) Electrification involves switching
energy uses including transportation and building heating off of
fossils fuels and onto low-carbon electricity, and (4) Capturing carbon
that would otherwise be emitted from power plants and industrial
facilities--with the captured carbon either stored permanently
(sequestered) or used to create fuels like synthetic natural gas or
synthetic diesel, by combining the carbon with renewably-generated
hydrogen.
Figure 1 shows historical and projected energy system costs as a
share of State Gross Domestic Product (GDP). All scenarios evaluated in
this study are in line with historical energy costs in Florida and,
even with decarbonization, energy system costs are anticipated to
decline as a share of GDP. The highest cost scenario is the 100%
Renewable Primary pathway due to the emphasis on displacing all fossil
fuels by 2050, rather than continuing to use some small amount of the
lowest-cost fossil fuels and capturing and storing the associated
carbon. The lowest cost scenario is the Central scenario, which allows
for the most flexibility in terms of key decarbonization strategies.
Note that the costs within this chart do not reflect any of the
macroeconomic benefits of transitioning off of fossil fuels, including
improved air quality, avoided climate impacts (like avoided sea level
rise), reduced energy price volatility, and energy independence, which
could equal or exceed the net costs shown here.
Figure 1
Total energy system costs as percentage of GDP, historical
and projected for Florida.
Key Actions by Decade
Achieving the transition described above is not expensive but
requires significant changes in public policy. Some of the key policy
challenges that must be managed in all scenarios include: (a) managing
tradeoffs between using land for low carbon electricity generation
(like wind farms and solar arrays) and improving natural carbon storage
in forests and soils; (b) electricity market designs that maintain
natural gas generation capacity for reliability while using gas
generators very infrequently; (c) developing electricity rates that
incentivize customers to flex their energy use to better match periods
of electricity surplus and shortage that come with intermittent
renewables like wind and solar; (d) encourage the development of carbon
capture industries that can leverage periods of excess electricity
generation; (e) coordination of planning and policy across sectors that
previously had little interaction, such as transportation and
electricity; (f) coordination of planning and policy across
jurisdictions; (g) mobilizing investment for a rapid low carbon
transition; and [h]) investing in ongoing modeling, analysis, and data
collection that informs both public and private decision-making. These
topics are discussed in more detail in Policy Implications of Deep
Decarbonization in the United States.
Achieving this transformation in Florida by mid-century at lowest
cost requires an aggressive deployment of low-carbon technologies,
including:
2020s
Begin large-scale transition to electric technologies in key
sectors; moving to electric light duty vehicles and electric
heat pumps.
Use coal fired power plants only when absolutely necessary,
prioritizing all other sources of electricity generation first.
Begin retiring coal assets.
Ramp up construction of renewable electricity generation and
upgrade electricity transmission where needed.
Allow strategic replacement of natural gas power plants to
support rapid deployment of low-carbon generation. These power
plants must be financed with the understanding that they will
run very infrequently to provide capacity, not as they are
operated today.
Maintain existing nuclear power plants.
Pilot new technologies that will need to be deployed at
scale after 2030.
Stop developing new infrastructure to transport and process
fossil fuels.
Begin building carbon capture for large industrial
facilities.
2030s
Maximum build-out of renewable electricity generation.
Nearly 100% of new vehicle sales and new building heating
systems using electric technologies.
Begin large-scale production of biodiesel and bio-jet fuel.
Large scale carbon capture on industrial facilities.
Build out electrical energy storage.
Deploy new natural gas power plants capable of 100% carbon
capture if they exist.
Maintain existing nuclear power plants.
Continue to reduce generation from gas-fired power plants.
2040s
Complete the transition to electric technologies for key
sectors; virtually 100% of light duty vehicles and building
heating systems run on electricity.
Produce large volumes of hydrogen for use in freight trucks
and fuel production.
Use synthetic fuel production to balance and expand
renewable generation.
Fully deploy biofuel production with carbon capture.
Further limit gas generation to infrequent periods when
needed for system reliability.
* * * * *
Technical Supplement
The following technical supplement shows results for the U.S. as a
whole as well as scenario figures not shown in the body of the main
report for Florida.
U.S. Results
Figure 30
E&I CO2 emissions trajectories--U.S.
Figure 31
CO2 emissions by final energy/emissions category.
Figure 32
Cumulative E&I CO2 emissions trajectories.
Figure 33
Four pillars of deep decarbonization--U.S.
Figure 34
Final and primary energy demand for all scenarios from 2021-
2050--U.S.
Figure 35
Components of emissions reductions in the Central scenario--
U.S.
Figure 36
Components of emissions reductions in the Low Biomass
scenario--U.S.
Figure 37
Components of emissions reductions in the Low Electrification
scenario--U.S.
Figure 38
Components of emissions reductions in the No New Regional TX
scenario--U.S.
Figure 39
Components of emissions reductions in the 100% Renewable
Primary scenario--U.S.
Figure 40
Annual net system cost premium above baseline in $2018 and as
% of GDP--U.S.
Figure 41
Net Change in E&I System Spending--U.S.
Figure 42
Total energy system costs as % of GDP--historical and
projected--U.S.
Letter 4
on behalf of agricultural retailers association, et al.
Hon. David Scott, Hon. Glenn Thompson,
Chairman, Ranking Minority Member,
House Committee on Agriculture, House Committee on Agriculture,
Washington, D.C.; Washington, D.C.
The farmers, cooperatives, researchers, retailers, seed producers,
scientists and technology developers represented by the organizations
signed below appreciate the opportunity to provide a statement for the
record for the House Agriculture Committee hearing on February 25, 2021
addressing ``Climate Change and the U.S. Agriculture and Forestry
Sectors.'' We commend the Committee for addressing this important and
complex issue. As organizations who embrace the use of crop varieties
improved through biotechnology and recognize the many benefits this has
enabled American agriculture to achieve, we want to specifically
highlight the fact that agricultural biotechnology needs to be a part
of any climate change discussion. Agriculture has achieved notable and
well documented environmental improvements through the adoption of crop
varieties improved through biotechnology that have enabled improved
tillage practices, improved soil health and greatly reduced greenhouse
gas (GHG) emissions, to name just a few. We are proud of the
accomplishments achieved to date but are even more excited about the
potential environmental benefits and climate change mitigation that
could be possible through the continued development and adoption of new
crop varieties improved with the help of innovative breeding methods
such as gene editing, marker assisted selection, genomic selection and
genetic engineering; new crop varieties that can produce more with
less--less water, less land, less inputs.
We support the ongoing public and private investment in the
research and development of new breeding methods which have the
potential to enhance the sustainability of agriculture, the
environment, and our global food system. In order for U.S. agriculture
to lead in the future, we must have access to every tool available to
address pressing challenges caused by climate change such as severe
weather events and rapidly evolving pests and diseases. We must do this
while meeting societal expectations for reductions in the use of crop
inputs and increasing new varieties of healthy and affordable food and
fiber options. Technology will be helpful in confronting these
challenges but we believe that biotechnology has demonstrated a unique
ability to meet these demands.
Our associations strongly support a regulatory system which fosters
innovation, values the environmental benefits that crops improved using
biotechnology enable, and recognizes the long and safe track record of
plant breeding, and the overwhelming evidence of the safe use of
genetic engineered plants. Congress should continue to encourage
Federal agencies to broadly communicate how their policy decisions
related to new plant varieties enable agriculture and forestry to
further contribute to climate solutions. In 2020, the United States
Department of Agriculture called for public input on the Agriculture
Innovation Agenda to help ``stimulate innovation so that American
agriculture can achieve the goal of increasing U.S. agricultural
production by 40 percent while cutting the environmental footprint of
U.S. agriculture in half by 2050.'' \1\ In a summary of the key
findings from all of the feedback received, USDA published the
``Agriculture Innovation Agenda: Scorecard Report.'' A key finding of
that report was that a primary driver of productivity growth is
``improvements in animal and crop genetics.'' \2\ Biotechnology is a
critical tool in plant breeding to enhance the efficiency and efficacy
of improvements in genetics that will maintain American agriculture as
the world leader in efficiency and sustainability.
---------------------------------------------------------------------------
\1\ https://www.usda.gov/aia.
\2\ Agriculture Innovation Agenda: Scorecard Report, https://
www.usda.gov/sites/default/files/documents/aia-scoreboard-report.pdf,
page 4.
Editor's note: the report referred to is also retained in Committee
file.
---------------------------------------------------------------------------
The men and women represented by our associations believe in the
vital contributions that our agriculture community can make to mitigate
climate change and build toward a more sustainable and equitable food
system. We believe in science and evidence-based solutions. We must
acknowledge that scientific innovations, such as agricultural
biotechnology, have resulted in environmental and societal benefits;
and must continue to be a part of the comprehensive strategy on climate
change and U.S. agriculture.
Thank you again for the opportunity to provide this statement for
the record.
Sincerely,
Agricultural Retailers Association National Association of Wheat
Growers
American Farm Bureau Federation National Corn Growers Association
American Seed Trade Association National Cotton Council
American Soybean Association National Council of Farmer
Cooperatives
American Sugarbeet Growers National Sorghum Producers
Association
Beet Sugar Development Foundation Produce Marketing Association
Biotechnology Innovation Syngenta
Organization
Crop Science Society of America U.S. Canola Association
Letter 5
on behalf of american society of agronomy, et al.
March 3, 2021
Hon. David Scott, Hon. Glenn Thompson,
Chairman, Ranking Minority Member,
House Committee on Agriculture, House Committee on Agriculture,
Washington, D.C.; Washington, D.C.
RE: Climate Change and the U.S. Agriculture and Forestry Sectors,
Outside Witness Testimony
Dear Chair Scott and Ranking Member Thompson:
The American Society of Agronomy (ASA), Crop Science Society of
America (CSSA), and Soil Science Society of America (SSSA) represent
more than 8,000 scientists in academia, industry, and government,
12,500 Certified Crop Advisers (CCA), and 781 Certified Professional
Soil Scientists (CPSS). We are the largest coalition of professionals
dedicated to the agronomic, crop and soil science disciplines in the
United States.
The House Agriculture Committee's timely hearing on Climate Change
demonstrates what the Societies also know--that agriculture and
forestry are the linchpins of America's fight against climate change.
Agricultural and forest soils have the potential to sequester enough
carbon to make America carbon neutral, if not a carbon sink. American
agriculture represents about ten percent of the country's greenhouse
gas emissions, and agriculture accounts for nearly twenty-five percent
of emissions globally.\1\ It does not need to be this way. Farmed soils
have between 25 and 75 percent less carbon than undisturbed soils,
which means that agriculture has the potential to be a significant
carbon sink,\2\ providing as much as 0.2 Gt CO2 equivalents
per year by 2050.\3\ American farmers can become globally recognized
climate heroes by sequestering more than \1/5\ of U.S. carbon
emissions, all without interfering with food production.\4\ Forest
activities, such as reforestation, improved forest management, and
reduced deforestation have the potential for even greater carbon
sequestration. The technical potential for carbon uptake by forest
measures is estimated to be from 0.5 to 1.5 Gt CO2
equivalents per year by 2050. Forest managers and agroforestry
producers along with farmers and rangers are poised to deliver enormous
emissions reductions and offsets from elsewhere in the economy.
---------------------------------------------------------------------------
\1\ https://www.epa.gov/ghgemissions/sources-greenhouse-gas-
emissions, https://www.epa.gov/ghgemissions/global-greenhouse-gas-
emissions-data#Sector
\2\ Lal, Rattan. ``Managing soils and ecosystems for mitigating
anthropogenic carbon emissions and advancing global food security.''
BioScience 60.9 (2010): 708-721.
Editor's note: entries annotated with are retained in Committee
file.
\3\ E. Larson, et al. ``Net-Zero America: Potential Pathways,
Infrastructure, and Impacts, interim report.'' Princeton University,
Princeton, NJ. December 15, 2020.
\4\ Fargione, Joseph E., et al. ``Natural climate solutions for the
United States.'' Science Advances 4.11 (2018): eaat1869.
---------------------------------------------------------------------------
Rural Americans have a strong voice in Congress through this
Committee, but the fact that many rural Americans see environmental
protection as destructive to their very livelihoods and way of life is
an existential liability for the planet. We urge the Committee to
quickly implement science-based policies that curb and mitigate climate
change's effects while empowering producers with new tools, new sources
of income, and the pride that comes from global recognition of their
efforts.
Put Carbon Into Soil
Carbon-Rich Farms Are Healthy Farms
Sequestering carbon on farmland is critical to maintaining a
healthy planet for generations to come. Sustainable agriculture that
focuses on a broad, systems approach that returns carbon to the soil
and builds soil organic matter has the double effect of pulling carbon
out of the atmosphere and building healthier soils.\5\ Soils with more
organic matter absorb and retain more moisture, reducing the need for
irrigation and increasing a farm's resilience to the damage associated
with droughts or flooding.\6\ More specifically, farms with high soil
organic matter require fewer additional fertilizers and can produce
healthier crops and higher yields.\7\
---------------------------------------------------------------------------
\5\ Lal, Rattan. ``Enhancing crop yields in the developing
countries through restoration of the soil organic carbon pool in
agricultural lands.'' Land Degradation & Development 17.2 (2006): 197-
209.
\6\ Basche, Andrea. ``Turning Soils Into Sponges: How Farmers Can
Fight Floods and Droughts.'' UCS, editor Washington, DC (2017): 1-18.
\7\ Lal, Rattan. ``Soil carbon sequestration impacts on global
climate change and food security.'' Science 304.5677 (2004): 1623-
1627.
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Awareness of Best Practices Is Key
Practices to sequester carbon include: no or low tillage; cover
crops; diverse crop rotations, sometimes including grazing animals;
land applications of manure, biosolids or urban compost; and precision
agriculture.\8\ These techniques are based in science, but widespread
adoption in the United States is hampered by a variety of factors, one
of which is awareness. The U.S. Department of Agriculture (USDA) and
universities use Extension agents on a county level to deliver
knowledge discovered through research to the farmers who can directly
apply it on their land, but funding for Extension in real dollars has
declined, as has the number of Extension agents available to farmers.
Congress should triple the funds for conservation technical assistance
to empower a new Climate Conservation Corps, with NRCS, Certified Crop
Advisors, and university Extension employees serving as the boots-on-
the-ground to help farmers transition to a new carbon economy.
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\8\ Montgomery, D.R. (2017). Growing a revolution: bringing our
soil back to life. WW Norton & Company.
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Make Sure Techniques Are Cost-Effective
Concern over potential extra costs associated with switching to
new, unfamiliar systems can be alleviated by USDA programs. For
example, USDA could be funded to develop a cloud-based cover crop
support tool that is easy to use, freely available nationally, and
locally specific. The tool would give detailed recommendations for
which crops to plant, seeding rates, and more. It would also provide
long-term economic data for transitions to demonstrate a producer's
likely return on investment, and, given adherence to its
recommendations, USDA could offer loans that cover extra costs and
potential lost income for the first 5 years to promote implementation.
Once a transition is achieved, USDA could reduce insurance rates for
the farm's now less risky, more resilient system. Crop insurance
subsidies that are more generous and flexible to producers engaging in
sustainable practices will encourage these practices and, subsequently,
reduce risk.\9\ So as not to disadvantage producers who have already
made investments in cover crops, for farmers who have already have a 5
year or longer history of successful cover crop management experience,
insurance premiums can be reduced to offset a portion of their
investment and to not leave these pioneering early adopters behind.
Important to note, these interventions become exponentially more
effective with access to broadband, making rural connectivity a key
driver to enabling sustainable practices.
---------------------------------------------------------------------------
\9\ Pan, William L., et al. ``Integrating Historic Agronomic and
Policy Lessons with New Technologies to Drive Farmer Decisions for Farm
and Climate: The Case of Inland Pacific Northwestern U.S.'' Frontiers
in Environmental Science 5 (2017): 76.
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Carbon Markets Require Scientific Legitimacy
Congress should consider policies that facilitate ecosystem
services markets for producers to earn money directly from sequestering
carbon, reducing emissions, preventing erosion, enhancing water
quality, and improving the viability of carbon land sinks in both
agricultural and forested lands. Such a market needs to be created and
maintained with the most up-to-date science. Science is always moving
forward--new information is constantly discovered, but this must not
impede a market from forming now, nor should such a market be prevented
from incorporating new findings as they come. Investments in ecosystems
science, which includes, for example, soil science, agronomy, forestry,
and data science working together, will inform a trusted market that
accurately measures and values ecosystem services. Importantly, a lack
of science underpinning such a market will greatly degrade trust in its
value. This would lead not only to the system's demise but it could
also doom future plans to pay producers for ecosystem services, even if
subsequent ideas are defensible.
Hundreds of millions of dollars per year in soil and forestry
research are needed over the next decade to establish ecosystem health
benchmarks so that best practices can be developed for producers over
wide geographic ranges. There are proven means of management-based soil
carbon sequestration,10-12 but which practices have the
largest impact, and where these practices can be optimized, is
essential information for valuing ecosystem credits. Also necessary are
rapid soil tests that validate these benchmarks. USDA's National
Institute of Food and Agriculture (NIFA) should carve out funding for
research on soil and forest health and the sustainable, systems-based
approaches that return carbon to the soil and build soil organic
matter. Congress should fully fund AgARDA with a mandate to invest in
high-risk and complex, systems-level research for improving carbon land
sinks.
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\10\ Poeplau, Christopher, and Axel Don. ``Carbon sequestration in
agricultural soils via cultivation of cover crops--A meta-analysis.''
Agriculture, Ecosystems & Environment 200 (2015): 33-41.
\11\ Luo, Zhongkui, Enli Wang, and Osbert J. Sun. ``Can no-tillage
stimulate carbon sequestration in agricultural soils? A meta-analysis
of paired experiments.'' Agriculture, Ecosystems & Environment 139.1-
2 (2010): 224-231.
\12\ McDaniel, M.D., L.K. Tiemann, and A.S. Grandy. ``Does
agricultural crop diversity enhance soil microbial biomass and organic
matter dynamics? A meta-analysis.'' Ecological Applications 24.3
(2014): 560-570.
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Invest in Conservation
Expand Conservation Programs Like the Conservation Reserve Program
(CRP) and the Environmental Quality Incentives Program (EQIP)
Congress has decided that for some lands, the ecological impacts of
farming outweigh the potential economic benefit to the producer. The
Conservation Reserve Program (CRP) is an option Congress gives
producers that pays them to take this land out of production and to
restore forests and grasslands. But producers may decide that the
potential profit made by planting crops could outweigh the CRP
payments, compelling producers to plant on land better suited to
conservation. Congress should adjust CRP guidelines to incentivize
conservation under a variety of economic circumstances. The guidelines
should also be amended to focus primarily on the marginal lands the
program was intended to protect, while lands better suited to
production should be channeled to the Environmental Quality Incentives
Program (EQIP). EQIP is an excellent way to provide funding for
conservation practices on working lands, but it is oversubscribed.
Congress should allocate more funding for this program.
Water and Irrigation Research Helps Producers and Preserves Natural
Ecosystems
Agriculture accounts for approximately 80 percent of freshwater use
in the United States \13\ because irrigation can double or even triple
grain yields in managed agriculture.\14\ But even as irrigation helps
producers grow more food on less land, extreme weather events and
increased development put pressure on freshwater resources. Research on
improved regional irrigation strategies and on crops that require less
water is key. This research has the combined benefit of helping
producers withstand droughts and floods while preserving more
freshwater for natural ecosystems and human consumption.\15\
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\13\ https://www.ers.usda.gov/topics/farm-practices-management/
irrigation-water-use/.
\14\ Kukal, Meetpal, and Suat Irmak. ``Irrigation-limited yield
gaps: trends and variability in the United States post-1950.''
Environmental Research Communications (2019).
\15\ Basche, Andrea D., and Marcia S. DeLonge. ``Comparing
infiltration rates in soils managed with conventional and alternative
farming methods: a meta-analysis.'' BioRxiv (2019): 603696.
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Diverse Crops And Markets Make Resilient Farms
As new weather patterns change which crops producers can grow,
science needs to step in with new options to keep farms resilient.
Research is needed to help current commodity crops adapt, but producers
and their lands will benefit from a new generation of climate-resilient
crops that are better at carbon sequestration and nitrogen use
efficiency and more tolerant of droughts and floods. USDA can partner
with universities and industry to breed these desperately needed crops.
AQUAmax corn and perennial grain crops, for example, are promising new
options. Research and partnerships to produce these crops rely on the
USDA National Plant Germplasm System and USDA gene banks, which
preserve and develop plant genetic resources, such as
seeds.16-17 The genetic resources contained in USDA gene
banks will be utilized more intensively, both for adapting existing
crops and for introducing new crop species or crop uses to changing and
more variable environments.
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\16\ Gepts P. (2006) Plant genetic resources conservation and
utilization: The accomplishments and future of a societal insurance
policy. Crop Science 46: 2278-2292 doi: 10.2135/
cropsci2006.03.0169gas.
\17\ Byrne P.F., Volk G.M., Gardner C., Gore M.A., Simon P.W.,
Smith S. (2018) Sustaining the future of plant breeding: the critical
role of the USDA-ARS National Plant Germplasm System. Crop Science 58:
451-468 doi: 10.2135/cropsci2017.05.0303.
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Crop diversification will require expanded markets and market
diversification, enabling producers to weather crop price fluctuations,
and diverse crop rotations are a tenant of a soil health-centered
agriculture--a win-win for both producers and climate.\18\ Agronomic
research should widen to include a multitude of crops, agroecoforestry,
and the investments needed in economics, marketing, and outreach to
prepare for commercial production and expand their markets. Perennial
crops, such as perennial grain crops, for example, have the potential
to sequester carbon year after year while saving producers money in
seeds and planting and enhancing biodiversity,\19\ but market
infrastructure is key to ensuring profitability at comparable levels to
current commodities.
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\18\ Pan, William L., et al. ``Integrating Historic Agronomic and
Policy Lessons with New Technologies to Drive Farmer Decisions for Farm
and Climate: The Case of Inland Pacific Northwestern U.S.'' Frontiers
in Environmental Science 5 (2017): 76.
\19\ Glover, Jerry D., et al. ``Increased food and ecosystem
security via perennial grains.'' Science 328.5986 (2010): 1638-1639.
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Expand On-Farm Energy Production Through Biofuel Systems
Biofuels play an important role in meeting global energy demands,
but many crops traditionally used for bioethanol production, such as
corn (maize), sugarcane, and sugar beets, are more valuable as food and
feed sources. Because the priorities of energy and food are in constant
competition, these types of biofuel crops will not be able to meet
rising global energy demands. Instead, investments are needed to
research and deploy biofuel systems that use agricultural residues and
food waste while promoting sustainable land use.\20\
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\20\ Gupta, Anubhuti, and Jay Prakash Verma. ``Sustainable bio-
ethanol production from agro-residues: a review.'' Renewable and
Sustainable Energy Reviews 41 (2015): 550-567.
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Nitrogen Management Research Benefits the Planet and the Producer's
Bottom Line
The use of industrially produced nitrogen fertilizers on farms has
saved billions from starvation and substantially reduced the amount of
land that would have been cleared for agriculture. But applied nitrogen
that a crop does not use immediately can lead to contaminated
waterways, causing ``dead zones'' and ``do not drink'' water
advisories. Excess nitrogen in the soil also converts to the potent
greenhouse gas nitrous oxide,21-22 which causes three
hundred times more global warming than carbon dioxide.
---------------------------------------------------------------------------
\21\ Canfield, Donald E., Alexander N. Glazer, and Paul G.
Falkowski. ``The evolution and future of Earth's nitrogen cycle.''
Science 330.6001 (2010): 192-196.
\22\ Snyder, C.S., et al. ``Agriculture: sustainable crop and
animal production to help mitigate nitrous oxide emissions.'' Current
Opinion in Environmental Sustainability 9 (2014): 46-54.
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Researchers are discovering new ways to reduce nitrogen
applications without compromising yields. Precision agriculture, for
example, is a promising technology powered by artificial intelligence
that requires rural broadband for high-speed wireless connectivity. It
combines best practices with on-farm data and digitally enabled
equipment so that fertilizers can be applied according to variabilities
across a field. This represents a major paradigm shift from managing an
entire field the same way. Meanwhile, management techniques take
advantage of rotations with crops that produce, or ``fix,'' their own
nitrogen from the air, and a recent discovery of nitrogen fixation in a
corn (maize) landrace represents a huge potential for reducing nitrogen
applications worldwide,\23\ should researchers harness its potential in
commercial varieties.
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\23\ Van Deynze, Allen, et al. ``Nitrogen fixation in a landrace of
maize is supported by a mucilage-associated diazotrophic microbiota.''
PLoS Biology 16.8 (2018): e2006352.
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Research and Extension Are Vital
Agricultural producers need healthy soils that sequester carbon,
resist flooding, and retain moisture; they need Extension experts and
Certified Crop Advisors who can rapidly bring them up to speed on the
latest best practices; they need cost-effective policies that
incentivize conservation and follow the latest science; and they need
resilient crops and robust markets for them. Each of these needs can be
met with increased investments in Extension and agricultural and
forestry research on soil and ecosystem health, agricultural and
forestry best practices, and a diversity of crops. Resilient,
sustainable farms, forests, and ranches of the future must be our
legacy.
Thank you for your consideration. For additional information or to
learn more about the ASA, CSSA, and SSSA please contact Karl Anderson,
Director of Government Relations, Redacted or Redacted. We look forward
to hearing from the Committee on how our membership's expertise can
help farmers become climate heroes.
Cc: Members of the House Agriculture Committee.
Letter 6
biotechnology innovation organization
February 25, 2021
Hon. David Scott, Hon. Glenn Thompson,
Chairman, Ranking Minority Member,
House Committee on Agriculture, House Committee on Agriculture,
Washington, D.C.; Washington, D.C.
Dear Chairman Scott, Ranking Member Thompson, and Members of the
Committee:
The Biotechnology Innovation Organization (BIO) is pleased to
submit a statement for the record to the to the United States House of
Representatives Committee on Agriculture hearing entitled, ``Climate
Change and the U.S. Agriculture and Forestry Sectors.''
Introduction
BIO\1\ represents 1,000 members in a biotech ecosystem with a
central mission--to advance public policy that supports a wide range of
companies and academic research centers that are working to apply
biology and technology in the energy, agriculture, manufacturing, and
health sectors to improve the lives of people and the health of the
planet. BIO is committed to speaking up for the millions of families
around the globe who depend upon our success. We will drive a
revolution that aims to cure patients, protect our climate, and nourish
humanity.
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\1\ https://www.bio.org/.
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Fighting Climate Change Through Biotechnology Innovation
BIO applauds the Committee for putting its immediate focus on the
climate crisis. As we outline in our attached ``100 Days of
Innovation'' Blueprint \2\ (Appendix I), our nation is at a critical
juncture. The start of the new administration and new Congress presents
a unique opportunity to come together to galvanize our nation's
scientific and entrepreneurial capacity, to mobilize new waves of
homegrown innovation and American ingenuity to tackle the climate
crisis, end the pandemic, and get more Americans back to work.
---------------------------------------------------------------------------
\2\ https://archive.bio.org/sites/default/files/docs/toolkit/
BIO_100_Days_of_Innovation.pdf.
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COVID-19 has also exposed the vulnerabilities and inequalities in
how communities are disproportionately impacted, our capacity to
respond to crisis, our ability to maintain our supply chains, and to
withstand an economic downturn. These challenges will only grow more
prevalent and damaging because of climate change.
To meet the challenge of climate change, it is crucial to lead with
science and U.S. innovation. We must incentivize the adoption of
innovative, sustainable technologies and practices; and streamline and
expedite regulatory pathways for breakthrough technology solutions.
Investment and deployment of cutting-edge technologies will be crucial
to ensure farmers, ranchers, sustainable fuel producers, and
manufacturers are able to respond to climate change and maintain the
U.S.'s global leadership in agriculture. This includes removing
barriers and assisting beginning and socially disadvantaged farmers and
ranchers to access and utilize these technologies, so all producers can
adapt to the challenges ahead. By accelerating and deploying
innovation, American agriculture can be resilient, self-sustaining, and
drive our economic recovery.
BIO supports legislative action on climate change that catalyzes
resilient and sustainable biobased economies. Federal climate policy
should use science-based targets to increase the use of biobased
manufacturing, low-carbon fuels, and sustainable agricultural
solutions. Science-based policy will promote resilient and sustainable
supply chains across economic sectors including translating
sustainability to best practices to all bioindustries. If done right,
climate legislation will create market pull incentives for investment
in and use of innovative technologies and products that fight climate
change.\3\ This will enable U.S. agriculture to combat climate change
while producing enough food, feed, fuel, and fiber for a growing world.
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\3\ https://www.bio.org/strategic-vision.
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Biotech Achievements
The adoption of biotechnology in agriculture and the development of
biobased technologies has already contributed to food security,
sustainability, and climate change solutions. The acceptance of
biotechnology has enabled large shifts in agronomic practices that have
led to significant and widespread environmental benefits. Some biotech
climate solutions include:
Biotech crops, such as those that require no-tilling, have
saved 27.1 billion kg of carbon dioxide, equivalent to taking
16.7 million cars off the road.\4\
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\4\ https://www.isaaa.org/resources/publications/briefs/54/
executivesummary/default.asp.
Editor's note: entries annotated with are retained in Committee
file.
Synthetic biology enables farmers to enhance soil health to
grow more food on less land, manufacturers to create new food
ingredients and alternative proteins, and industrial biotech
companies to revolutionize manufacturing by optimizing
processes for producing sustainable chemicals, biobased
products, and biofuels.\5\
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\5\ https://www.bio.org/blogs/synthetic-biology-sustain-
agriculture-and-transform-food-system.
The use of feed additives for ruminant livestock, has been
demonstrated to reduce methane levels produced by ruminants by
up to 30 percent \6\ while the addition of enzymes \7\ to
chicken feed promotes better protein digestibility, which helps
reduce residual nitrogen emissions from manure.
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\6\ https://newfoodeconomy.org/feed-additive-methane-cow-burps/.
\7\ https://www.novozymes.com/en/news/news-archive/2017/03/more-
from-one-acre-new-report.
New research \8\ shows emissions from sustainable fuels made
from corn are 46 percent lower than gasoline. Advanced and
cellulosic biofuel technologies can reduce emissions from 101
to 115 percent.\9\
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\8\ https://iopscience.iop.org/article/10.1088/1748-9326/abde08.
\9\ https://www.eesi.org/articles/view/biofuels-versus-gasoline-
the-emissions-gap-iswidening#:
:targetText=Argonne%20researchers%20show%20that%20compared,
for%20the%20RFS%20from
%202010.
Renewable chemicals and biobased products removed 12.7
million metric tons of CO2 from the manufacturing
sector in 2016 alone, and can continue to green our supply
chains, reduce plastic pollution, and provide sustainable
alternatives to fossil-based products.\10\
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\10\ https://www.biopreferred.gov/BPResources/files/
BiobasedProductsEconomicAnalysis
2018.pdf.
To learn more about these technologies and the innovative
breakthroughs that can reduce greenhouse gas emissions throughout
agricultural supply chains, please see BIO's attached comments \11\
(Appendix II) to the U.S. Department of Agriculture's (USDA)
Solicitation of Input from Stakeholders on Agricultural
Innovations.\12\
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\11\ https://www.bio.org/letters-testimony-comments/bio-submits-
comments-usda-ag-innovation.
\12\ https://www.govinfo.gov/content/pkg/FR-2020-04-01/pdf/2020-
06825.pdf.
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Policy Recommendations
As the Committee and Congress examine policies to combat climate
change, while also aiming to strengthen the economy and create jobs,
BIO recommends the following policy approaches:
Incentivize Modern Ag Techniques. Enable America's farmers,
ranchers, and foresters to combat climate change by
incentivizing the adoption of modern agricultural techniques
and innovative technologies, including carbon sequestration,
enhancing animal feed with enzymes, microbes to reduce
emissions from livestock, precision plant breeding, and
biostimulants and microbial inoculants--which boost production
by building up soil carbon and using less fertilizer. This also
includes:
Helping producers solve the technical entry barriers
to participating in carbon credit markets as proposed in
the Growing Climate Solutions Act.
Incentivizing farm management decisions that have
large impact on reducing GHG emissions and increasing soil
organic carbon, such as expanding section 45Q of the Tax
Code to credit.
Bolster U.S. Department of Agriculture (USDA)
conservation programs to promote improved soil health and
carbon sequestration.
Certify Sustainable Ag Practices. Create a certification
program at USDA to allow producers to participate in carbon
credit markets which will enable the manufacturers of biobased
fuels, chemicals, plastics, food, animal feed, veterinary
products, and everyday materials to reliably demonstrate their
true environmental benefit--from farm to consumer.
Promote Animal Biotechnology Innovations. Genetic innovation
in animals can help prevent and respond to future infectious
diseases. These technologies hold enormous potential to address
numerous agricultural, environmental, humanitarian, and public
health challenges associated with climate change by enabling
animal agriculture to produce more protein with fewer animals
and adapting livestock to a warming world. We need to
streamline oversight of animal biotechnology to create a clear,
timely, and science-based regulatory approval process that
provides a viable path to market for these critical new
innovations.
Streamline Approval Process for Innovative Feed Additives.
Feed additives are key for promoting robustness and resilience
in livestock through improved nutrition. Furthermore, they
improve the return on investment for farmers and reduce
greenhouse gas emissions. Unfortunately, many of these new
innovative products lack a suitable regulatory product category
to ensure timely approval nationwide. An improved regulatory
process is necessary to bring these innovative technologies to
market to address climate change.
Modernize Evaluation of Veterinary Products. Disruptive
innovations and advances in veterinary products can increase
protein production while decreasing emissions from livestock.
To better account for these environmental benefits, the U.S.
Food and Drug Administration and USDA's methods to evaluate the
efficacy of these technologies must also evolve to properly
measure the climate and sustainability improvements they
provide.
Boost Access to Nutrition. Utilize technology to boost the
nutrient levels of fruits and vegetables. Biotech enables crops
to maintain yields in the face of drought and less water, which
has a direct bearing on improved food security and poverty
alleviation. Increased production from biotechnology crops can
help combat global hunger and malnutrition by increasing the
vitamin and mineral contents of plants.
Eliminate Food Deserts and Reduce Food Waste. Incentivize
the use of biotech in specialty crops to address the lack of
fresh fruits and vegetables in food deserts in urban and rural
communities. Biotech advancements allow for fewer blemishes,
such as bruises, that lead to more sellable crops for farmers
requiring less acreage. These technologies can also extend the
shelf life of produce, cutting down on food waste, which
creates eight percent of all global emissions.* [1]
Ensure biotech products are used to achieve the U.S.
Environmental Protection Agency (EPA) and USDA's Food Loss and
Waste Reduction Goal in alignment with Target 12.3 of the UN
Sustainable Development Goal to reduce food waste by 50 percent
by 2030. Additionally, support the development of bioplastics
from sustainable chemicals that can be recyclable,
biodegradable, or compostable to divert food packaging waste
from landfills.
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* Editor's note: the footnote reference in the document as
submitted is [1]. This is an endnote reference format, the extraneous
formatting is retained herein.
[1] http://www.fao.org/fileadmin/templates/nr/
sustainability_pathways/docs/FWF_and_cli
mate_change.pdf
Ensure Regulatory and Government Support Keep Pace with
Technology Advancements. Innovations like synthetic biology,
gene editing, cell culturing, and fermentation hold tremendous
potential to solve urgent challenges throughout the
agricultural supply chain which will only be compounded by
climate change. Producers and developers will need access to
these innovative technologies to increase production while
cutting down on their environmental footprint. Enabling
regulatory systems to keep pace with advancements in biology is
essential if society is expected to fully benefit from food,
health, and industrial products developed using the very latest
cutting-edge platform technologies. Furthermore, domestic
regulatory pathways must provide for more expedient approval
timelines to ensure the economics of new product development
are not a deterrent to bringing new products to market. In the
absence of a predictable and well-designed regulatory product
approval system developers may choose to invest in more mature
markets with better approval timelines. Investments by the
government in next generation of biotechnologies and genomics
---------------------------------------------------------------------------
will also be critical to meet the challenge of climate change.
Support Federal Biobased Procurement and Sustainability
Programs to Buy ``Green''. Enhance USDA Biopreferred program to
ensure that agencies are fulfilling their obligation to shop
Biopreferred. While the program has been successful in
certifying products over the years, procurement agencies have
not been held accountable to buy Biopreferred options where
available.
Also critical to the development of the biobased economy is
determining its value and identifying the segments which need
investment and research and development. Key to this is
updating the North American Industry Classification System
(NAICS) codes to establish measurements for biobased products
as required under the 2018 Farm Bill.
Accelerate Public and Private Research and Development to
Drive Investment in New Tools. Provide significant advances in
foundational tool development and practical applications
through supportive grants for research and development of new
tool start-ups. Foster coordination across agencies to advance
research and development in biomanufacturing, strengthening and
broadening the U.S.' synthetic biology capabilities and
developing the future bioeconomy workforce.
Expand incentives for Carbon Capture Utilization, and
Sequestration. This technology presents a significant
opportunity to transform the manufacturing sector and reduce
greenhouse gas emission by turning carbon into value added
products. Extend and expand incentives to support carbon
utilization and innovative technologies to bolster the
potential of direct air capture technologies. USDA should
develop a verification methodology suitable for products of
biological carbon capture and utilization (CCU) to expand
opportunities for U.S. biomanufacturing as directed by the 2018
Farm Bill.
Incentivize green manufacturing infrastructure. Spur
investment and development of biobased manufacturing through
supportive grants and tax incentives.
Develop a Federal Low Carbon Fuel Standard (LCFS). A LCFS
that is technology and feedstock neutral and builds on the
success of the Renewable Fuel Standard (RFS) to ensure
agriculture and low carbon, sustainable fuels are part of the
solution will significantly reduce emissions in transport.
Incentivize Advanced and Cellulosic Fuel Development.
Ensuring the growth of advanced and cellulosic biofuels
industry will require long-term tax incentives to avoid
creating uncertainty for investors and companies trying to
raise capital. The development of a long-term sustainable
aviation fuel specific blender's tax credit could attract
significant investment and address existing structural and
policy disincentives that have prevented the aviation biofuels
industry from taking off.
Bring New Sustainable Fuel Technologies to Market and
Recognize Environmental Benefit. Direct the EPA to approve
stalled pathways and facility registrations for advanced and
cellulosic biofuel technologies to spur investment and
development in sustainable fuels projects as proposed in S.
193. Because of biotech innovations, the production of biofuels
is becoming more efficient and environmentally sustainable. To
reflect these improvements, EPA should update its greenhouse
gas modeling as proposed in S. 218.
Investment in Research and Development and Grants to Develop
and Deploy Advanced Biofuels. To spur investment and
development of new biorefineries and deployment of advanced
biofuels, USDA's Biorefinery Assistance program and the
Department of Energy research and development programs should
be feedstock neutral. Investments in USDA's Higher Blends
Infrastructure Incentive Program (HBIIP) will help consumers
access low carbon fuels.
One Health Approach to Public Health Preparedness. One
Health represents a much-needed collaboration that would align
human health, animal health, and environmental health
strategies to create smarter, multifaceted, and coordinated
efforts, including to help enhance the ability of our planet to
adapt to climate change. The thoughtful and bipartisan
Advancing Emergency Preparedness Through One Health Act (S.
1903/H.R. 3771) from the 116th Congress directs the U.S. Health
and Human Services and USDA to coordinate with other agencies
and state and local leaders to advance a national One Health
framework to better prevent, prepare for, and respond to
zoonotic disease outbreaks like COVID-19. Doing so will help
insulate human populations from future infectious diseases,
antimicrobial resistance (AMR), and other heath challenges
arising from climate change.
Advance Global Climate Solutions. Build broad global support
for the U.S. government's recent regulatory modernization for
agricultural biotechnology and proactively advance
biotechnology as a valuable tool to combat climate change
through broad trade strategy approaches and efforts to reengage
in multilateral forums.
Conclusion
BIO is committed to working with the Committee, Congress, and the
Administration to address the climate crisis. We urge you to support
policy that advances pioneering technology breakthroughs. With science
we can return our nation and the world to health and prosperity by
taking bold and drastic action to address the climate crisis.
Appendix I
100 Days of Innovation
Our nation is at a critical juncture and how we approach the next
100 days will be essential in terms of ending the pandemic and
rebuilding our economy in a way that is more resilient, more dynamic,
and more inclusive. America remains the most vibrant and
entrepreneurial nation in the world. We have been tested time and time
again and have always emerged stronger and more united. As the new
Administration and new Congress begin, there is a unique opportunity
for the private and public sectors to come together to galvanize our
nation's scientific and entrepreneurial capacity, to mobilize new waves
of homegrown innovation and American ingenuity and to organize our
country around the clear and bold mission of ending the pandemic and
getting more American's back to work. To do that we must:
1. Ensure a Speedy Transition and an Expedited Senate Confirmation
Process for Agency Leadership Critical to Advancing Public
Health, Nutrition, and Environmental Goals.
2. Reengage as a Leader on the World Stage, Including Rejoining the
World Health Organization and the Paris Climate Accords.
3. Develop and Approve More Vaccines, Therapeutics, and Diagnostics
To Prevent and Treat COVID-19[:]
Specific Recommendations
Provide increased R&D funding for a broad array of
innovative technologies
with the potential to fight COVID-19 and other emerging
infectious dis-
eases.
Ensure ample funding to complete research priorities and
procurement of
existing vaccines and therapeutics.
Expand government coordination mechanisms beyond the
first wave of
COVID-19 vaccines, treatments, and diagnostics.
Encourage more public-private partnerships and private
investment
through sound public policy.
Continue expedited EUA and full approval processes for
existing and next
wave of COVID vaccines and therapies.
Ensure that companies can continue to partner with HHS,
BARDA and
DOD without regard to their current global supply chain.
Increase funding for CDC surveillance activities to help
evaluate the effec-
tiveness of COVID vaccines and therapeutics and drive
evidence-based deci-
sion making on development of updated or new medical
countermeasures.
4. Promote Robust and Equitable Patient Access to COVID-19 Vaccines,
Therapeutics, and Diagnostics[:]
Specific Recommendations
Eliminate all patient cost-sharing across government and
commercial insur-
ance markets for COVID-related vaccines, treatments, and
diagnostics, in-
cluding for administration and ancillary services.
Ensure state Medicaid programs cover all FDA-approved
COVID-19 treat-
ments and diagnostics, including those approved under an
EUA, without
delay and without prior authorization requirements.
Cover COVID-19 treatment for the uninsured via Medicaid
at 100%
Federal match.
Ensure that provider relief funds and other similar
assistance is targeted
to providers who serve Medicaid, the uninsured, and other
vulnerable pa-
tients.
Expand and adequately fund the range of sites
administering COVID-19
vaccines and treatments beyond acute care settings,
including home infu-
sion of therapeutics.
Mount a coordinated and well-funded national campaign to
build vaccine
confidence and facilitate vaccination, particularly in
minority communities
and among essential workers.
Develop a national vaccination plan to accelerate
distribution and adminis-
tration of COVID-19 vaccines in an equitable manner.
Leverage Federal research funding to diversify Federal
clinical trial net-
works and promote minority inclusion in COVID-19 trials.
Encourage governors to expand the vaccine eligible
populations to the ACIP
recommendations expediently.
5. Better Prepare for Future Infectious Disease Outbreaks[:]
Specific Recommendations
Support a steady-state of public and private R&D on
emerging infectious
diseases by providing tax incentives for private
investment in early-stage
clinical R&D of medical countermeasures.
Adequately fund and resource agencies engaged in
biodefense and emer-
gency preparedness such as ASPR, BARDA, USDA, and the
CDC, so they
have the infrastructure in place for immediate response
and can improve
long-term strategic preparedness planning.
Enable the creation, maintenance, and utilization of
advanced manufac-
turing capabilities domestically, particularly for
biological products by
incentivizing private investment in facilities and
equipment, supporting ini-
tiatives for training a new and expanded workforce, and
ensuring a clear
regulatory pathway.
Increase physical and virtual inventories of critical
emergency supplies in
the Strategic National Stockpile.
Pursue a ``One Health'' coordination approach across the
government that
recognizes the interrelationship between human, animal,
and environ-
mental health.
Rebuild and invest in the state and local public health
infrastructure.
6. Drive Economic Revival and BIO's Pledge Resiliency Through
Adoption of Advanced Biotechnology Solutions[:]
Specific Recommendations