[Senate Hearing 110-1210]
[From the U.S. Government Publishing Office]
S. Hrg. 110-1210
EFFECTS OF CLIMATE CHANGE AND OCEAN ACIDIFICATION ON LIVING MARINE
ORGANISMS
=======================================================================
HEARING
before the
SUBCOMMITTEE ON OCEANS, ATMOSPHERE, FISHERIES, AND COAST GUARD
OF THE
COMMITTEE ON COMMERCE,
SCIENCE, AND TRANSPORTATION
UNITED STATES SENATE
ONE HUNDRED TENTH CONGRESS
FIRST SESSION
__________
MAY 10, 2007
__________
Printed for the use of the Committee on Commerce, Science, and
Transportation
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SENATE COMMITTEE ON COMMERCE, SCIENCE, AND TRANSPORTATION
ONE HUNDRED TENTH CONGRESS
FIRST SESSION
DANIEL K. INOUYE, Hawaii, Chairman
JOHN D. ROCKEFELLER IV, West TED STEVENS, Alaska, Vice Chairman
Virginia JOHN McCAIN, Arizona
JOHN F. KERRY, Massachusetts TRENT LOTT, Mississippi
BYRON L. DORGAN, North Dakota KAY BAILEY HUTCHISON, Texas
BARBARA BOXER, California OLYMPIA J. SNOWE, Maine
BILL NELSON, Florida GORDON H. SMITH, Oregon
MARIA CANTWELL, Washington JOHN ENSIGN, Nevada
FRANK R. LAUTENBERG, New Jersey JOHN E. SUNUNU, New Hampshire
MARK PRYOR, Arkansas JIM DeMINT, South Carolina
THOMAS R. CARPER, Delaware DAVID VITTER, Louisiana
CLAIRE McCASKILL, Missouri JOHN THUNE, South Dakota
AMY KLOBUCHAR, Minnesota
Margaret L. Cummisky, Democratic Staff Director and Chief Counsel
Lila Harper Helms, Democratic Deputy Staff Director and Policy Director
Christine D. Kurth, Republican Staff Director, and General Counsel
Kenneth R. Nahigian, Republican Deputy Staff Director, and Chief
Counsel
------
SUBCOMMITTEE ON OCEANS, ATMOSPHERE, FISHERIES, AND COAST GUARD
MARIA CANTWELL, Washington, OLYMPIA J. SNOWE, Maine, Ranking
Chairman TRENT LOTT, Mississippi
JOHN F. KERRY, Massachusetts GORDON H. SMITH, Oregon
BARBARA BOXER, California JOHN E. SUNUNU, New Hampshire
BILL NELSON, Florida JIM DeMINT, South Carolina
FRANK R. LAUTENBERG, New Jersey DAVID VITTER, Louisiana
THOMAS R. CARPER, Delaware
AMY KLOBUCHAR, Minnesota
C O N T E N T S
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Page
Hearing held on May 10, 2007..................................... 1
Statement of Senator Cantwell.................................... 1
Statement of Senator Klobuchar................................... 5
Prepared statement of Hon. Olympia J. Snowe, U.S. Senator from
Maine.......................................................... 3
Statement of Senator Stevens..................................... 4
Witnesses
Conover, Ph.D., David O., Dean and Director, Marine Sciences
Research Center, Stony Brook University........................ 19
Prepared statement........................................... 20
Doney, Ph.D., Scott C., Senior Scientist, Department of Marine
Chemistry and Geochemistry, Woods Hole Oceanographic
Institution.................................................... 6
Prepared statement........................................... 7
Feely, Ph.D., Richard A., Supervisory Chemical Oceanographer,
Pacific Marine Environmental Laboratory, NOAA, U.S. Department
of Commerce.................................................... 13
Prepared statement........................................... 15
Hansen, Dr. Lara J., Chief Scientist, Climate Change Program,
World Wildlife Fund............................................ 24
Prepared statement........................................... 25
Kruse, Ph.D., Gordon H., President's Professor of Fisheries and
Oceanography, School of Fisheries and Ocean Sciences,
University of Alaska Fairbanks................................. 33
Prepared statement........................................... 35
Watkins, James D., Admiral (Ret.), U.S. Navy; Chairman, U.S.
Commission on Ocean Policy; Co-Chair, Joint Ocean Commission
Initiative..................................................... 43
Prepared statement........................................... 45
Appendix
Inouye, Hon. Daniel K., U.S. Senator from Hawaii, prepared
statement...................................................... 65
Lautenberg, Hon. Frank R., U.S. Senator from New Jersey, prepared
statement...................................................... 65
Response to written questions submitted by Hon. Maria Cantwell
to:
Scott C. Doney, Ph.D......................................... 66
Richard A. Feely, Ph.D....................................... 82
Dr. Lara J. Hansen........................................... 93
James D. Watkins............................................. 100
Response to written questions submitted by Hon. Daniel K. Inouye
to:
Scott C. Doney, Ph.D......................................... 66
Richard A. Feely, Ph.D....................................... 77
Dr. Lara J. Hansen........................................... 92
James D. Watkins............................................. 94
Response to written questions submitted by Hon. Frank R.
Lautenberg to:
Scott C. Doney, Ph.D......................................... 69
Richard A. Feely, Ph.D....................................... 84
EFFECTS OF CLIMATE CHANGE AND OCEAN
ACIDIFICATION ON LIVING MARINE ORGANISMS
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THURSDAY, MAY 10, 2007
U.S. Senate,
Subcommittee on Oceans, Atmosphere, Fisheries, and
Coast Guard,
Committee on Commerce, Science, and Transportation,
Washington, DC.
The Subcommittee met, pursuant to notice, at 10:22 a.m. in
room SR-253, Russell Senate Office Building, Hon. Maria
Cantwell, Chairman of the Subcommittee, presiding.
OPENING STATEMENT OF HON. MARIA CANTWELL,
U.S. SENATOR FROM WASHINGTON
Senator Cantwell. Good morning. The Senate Committee on
Commerce, Science, and Transportation and the Oceans,
Atmosphere, Fisheries, and Coast Guard Subcommittee hearing
will come to order. I thank the witnesses for their indulgence.
The Senate had a vote and some of my colleagues I am sure will
be joining us shortly. But I thought that we should go ahead
and get started. I thank you very much for being here.
I know that we have a distinguished set of witnesses: Dr.
Scott ``DONN-ey,'' is that right?
Dr. Doney. ``DOE-ney.''
Senator Cantwell. ``DOE-ney.'' Thank you very much.
Dr. Richard Feely; is that correct? I should know that,
given your presence in the Pacific Northwest. Dr. David
Conover, Dr. Lara Hansen, Dr. Gordon Kruse, and Admiral James
Watkins. Thank you for returning to the Committee and for your
steadfast involvement in this issue.
I know that some of you have PowerPoint presentations and
we will try to accommodate you this morning on that and give
you a few extra minutes and, as I said, as my colleagues arrive
we will also give them time to make opening statements.
I would like to again welcome each of you to this important
Committee to talk about the impact of climate change and ocean
acidification on our living marine resources. Today you
represent some of the top experts in the field of ocean and
climate change and I would like to thank each of you for your
testimony and for your leadership in this area.
Since the start of the Industrial Revolution 200 years ago,
humans have released over 1.5 trillion tons of carbon dioxide
into the atmosphere and only now are we beginning to understand
the implications of this. When scientists first started raising
questions about our carbon dioxide emissions in the 1950s, very
little was known about the possible consequences. Some
predicted that carbon dioxide would accumulate in the
atmosphere. Others predicted it would be absorbed by the
world's oceans. Today we know that both of those were correct.
Human-caused emissions have increased the global
atmospheric carbon dioxide concentration by 35 percent. In
addition, over half a trillion tons of carbon dioxide have been
absorbed by our oceans. We are already seeing the impacts of
this on our oceans and our coastal ecosystems. If we continue
with business as usual, the ecological, social, and economic
consequences are likely to be severe.
After extensive scientific research, climate scientists now
know that global warming is happening and it is happening
because of human use of fossil fuel. We are seeing more results
of global warming every day. Year after year, our polar ice
caps are receding, glaciers are shrinking rapidly, even
disappearing, and, to give one example from my home state, the
Intergovernmental Panel on Climate Change recently reported
that the mountain snow pack that feeds the Columbia River
system is shrinking away, producing less and less water for the
rivers every year.
While these easy-to-see impacts of global warming are
highly disturbing, we are here today to examine the impacts
that are not quite as visible, but yet just as severe: those
that occur beneath the surface of our oceans. The impact of
climate change on coastal communities from sea level rise and
increased storm intensity have been the focus of much
attention. But climate change also poses risks to our Nation's
multibillion dollar fishing industry. In fact, global warming
could threaten the very integrity of our oceans' ecosystem,
possibly wiping out more vulnerable ecosystems like coral
reefs.
These are frightening possibilities, but very real ones.
While it may not be easy to see the impacts of global warming
in the ocean, it is vital that we examine it. If we wait until
these problems are too painful or too obvious to ignore, it
will be far too late. While carbon dioxide is accumulating in
our atmosphere, it also is being absorbed by oceans, and
approximately one-third of carbon dioxide emissions end up in
the oceans.
For decades we assumed that the oceans would absorb these
greenhouse gases to the benefit of our atmosphere, with no side
effects for our seas. Emerging science now shows we were wrong.
Thanks in no small part to the work of our panelists; we now
know that the absorption of carbon dioxide actually changes the
very chemistry of our oceans. Sea water becomes more acidic and
begins to withhold the basic chemical building blocks needed by
many marine organisms. Coral reefs, the rain forests of the
sea, cannot build their skeletons, and in colder waters,
scientists predict, more acidic oceans can dissolve the shells
of tiny organisms that make up the base of the ocean's food
chain.
When it comes to ocean acidification, we risk not just
damaging the oceans' ecosystem; we are threatening its very
foundation. The social and economic costs to the world's
fisheries and fishery-dependent communities are incalculable.
Managers at the State and local and regional levels must be
able to anticipate and develop strategies to address these
threats.
The danger of global climate change and ocean acidification
can be illustrated with one example from my home state of
Washington. Washington is home to a very important salmon
population. Salmon are a $330 million industry in the Pacific
Northwest and certainly a cultural icon. As I mentioned
earlier, the global warming will continue to reduce the
snowpack that feeds our rivers will continue to have impacts.
As these waters become less, the waters will become warmer.
Salmon rely on a predictable, steady flow for their survival.
Every coastal State can point to examples like these, and
these examples are far too important to ignore. Both global
warming and ocean acidification have the same cause and the
same solution--we must reduce our emissions of carbon dioxide.
If we fail to address the potential impact of global climate
change and ocean acidification, we can be jeopardizing all we
have fought so hard for on ocean conservation and the gains
that have already been made. These are difficult words to hear,
I think, but reflect a difficult reality.
Again, I want to thank all of you for joining us and for
your hard work on this very important issue. We look forward to
your testimony.
I know I have been joined by Senator Stevens, the Ranking
Member of the full Committee, and I invite him to make any
opening comment, and to note that Senator Snowe is unable to
join us today because of a conflict, but is reviewing the
testimony and will be very involved in any further steps and
will look forward to seeing the testimony of the witnesses. But
I thank Senator Stevens for his participation and his presence
here this morning.
[The prepared statement of Senator Snowe follows:]
Prepared Statement of Hon. Olympia J. Snowe, U.S. Senator from Maine
Thank you, Madam Chair, for calling this critical hearing to
discuss how climate change may affect the future of our oceans and
their living marine resources. I am pleased that this committee is so
actively investigating the burgeoning issue of ocean acidification--a
topic that in just a few short years has developed from a relatively
unknown theory into what is potentially one of the most disconcerting
aspects of ocean-related climate science.
Lost in much of the discussion of climate change has been its
potential impacts on the oceans' corals, fish, and other species.
Recent research--much of it conducted by members of our esteemed panel
of witnesses--has indicated that as a direct result of the precipitous
increase in carbon dioxide in our atmosphere, our oceans are warming
and becoming more acidic. If we continue to allow emissions of carbon
dioxide to increase, we could see drastic, worldwide impacts in our
oceans, from species migration and coral bleaching to widespread
extinctions.
The oceans drive much of our Nation's economy, as well as that of
my home state of Maine. Throughout our state's history, stewardship of
our marine resources has pervaded our maritime activities. Nowhere is
this more evident than in our lobster fishery, which for generations
has engaged in self-imposed, sustainable fishing practices. The result
of that stewardship is a robust industry that landed over $270 million
worth of lobster in 2006. Today, that fishery faces potential danger.
Not from the activities of our lobstermen, but from the potential
effects of global climate change.
In 1999, the lobstermen of Long Island Sound began pulling up pots
full of dead lobster. According to a study by Connecticut's Sea Grant
program, that fall, commercial landings from western Long Island Sound
plummeted an astounding 99 percent from the previous year. Nearly
three-quarters of the Sound's lobstermen lost all of their income. The
study concluded that, ``the physiology of the lobsters was severely
stressed by sustained, hostile environmental conditions, driven by
above average water temperatures.'' In other words, warming ocean
temperatures created conditions that killed these lobsters and
decimated the fishery.
The lobster industry's collapse in Long Island Sound may be a
harbinger for other fisheries. Evidence is mounting that anthropogenic
emissions of greenhouse gasses--carbon dioxide in particular--are
disrupting the forces that drive our climate and in turn, our oceans.
Approximately a third to a half of global manmade carbon dioxide
emissions have already been absorbed into the world's oceans. This
amount will double by 2050, and all indications are that this will
increase the acidity of the oceans' surface and could initiate the
largest change in pH to occur in as many as 200 million years. Clearly,
the consequences of such a shift could be catastrophic. Which is why my
colleague Senator Kerry and I introduced S. 485, the Global Warming
Reduction Act of 2007. This legislation is the only introduced climate
bill that specifically calls for research to address the vulnerability
of marine organisms throughout the food chain to increased carbon
dioxide emissions. It also requires an assessment of probability that
such a change will cost us more than 40 percent of our coral reefs--
delicate ecosystems that are especially vulnerable to both ocean
acidification and warming.
And coral reefs are just as integral to the economy and heritage of
tropical states such as Florida and Hawaii as fisheries are to Maine.
In order to protect these resources, we must understand what is
happening to them. The final report of the U.S. Commission on Ocean
Policy, chaired by Admiral Watkins who is testifying before us today,
calls for development and implementation of a sustained Integrated
Ocean Observing System to provide the data necessary to understand the
complex oceanic and atmospheric systems--including pH, temperature,
salinity and the speed and direction of currents--that comprise our
oceans. I know the scientists here today also support that initiative,
and I support it as well.
In each of the past two Congresses, I have introduced a bill to
authorize an Integrated Ocean Observing System and develop a national
framework to oversee and our numerous, successful, independent regional
observing systems. Twice this bill has passed the Senate unanimously,
but failed to pass the House. I have introduced a new version of this
bill--the Coastal and Ocean Observation Systems Act of 2007, S. 950--in
the 110th Congress, with sixteen bi-partisan co-sponsors, and I am
working closely with members from both chambers to ensure that this
bill becomes law as soon as possible.
Mounting evidence linking carbon emissions to potentially
devastating changes in the hydrology of our oceans compels us to act
now to protect the future of the irreplaceable resources found beneath
the waves. I will continue to do everything in my power to provide our
scientists with the requisite tools to carry our their research and
ensure that we prevent further damage to these vital ecosystems. I
thank Doctors Feely, Conover, Doney, Kruse, and Hansen and Admiral
Watkins for taking the time to engage in what I believe will be a
fruitful and fascinating discussion, and I look forward to hearing all
of your testimony.
Thank you, Madam Chair.
STATEMENT OF HON. TED STEVENS,
U.S. SENATOR FROM ALASKA
Senator Stevens. Thank you very much.
To maintain our sustainable fisheries, it is important that
we try to understand how changes to the oceans' environment
affect our fish stocks. Much of the focus on Capitol Hill and
in the media is centered on how climate change will affect life
on land through higher temperatures, storms, and sea levels.
What many do not realize is that the oceans may change as well
and, as the chairwoman has said, if the predictions are
accurate these changes could have economic and serious
consequences.
Warm ocean temperatures are causing widespread coral
bleaching in the Caribbean. In Alaska some species are moving
north. There is concern about how these changes will affect the
fisheries off our shores--half the coastline of the United
States is in Alaska.
We know very little about these changes. We do not know how
much this change is due to natural variations and how much is
manmade. In Alaska our fisheries have been impacted in the past
due to natural variations in ocean temperature caused by the
Pacific Decadal Oscillation shifts in ocean currents. Some
fisheries in Alaska have flourished due to warmer temperatures.
Others have seen temporary declines.
I am pleased to see these panelists here today, Madam
Chairman. What we have been witnessing could have serious
consequences for marine life and fisheries worldwide, and I
know these panelists can help the Committee identify some of
the current gaps in our knowledge. We need to make sure the
Federal agencies have the resources in the right places to
study ocean acidification and climate change.
I thank the panelists. I do particularly thank Dr. Gordon
Kruse, who has traveled all the way from Juneau to participate
in today's hearing. Dr. Kruse has studied fisheries in Alaska
for decades, most recently serving as Chair of the Scientific
and Statistical Committee of the North Pacific Fishery
Management Council. Their Committee plays a vital role in what
the Pew Commission has stated is the best managed fishery in
the world, thanks to the science that Dr. Kruse and others have
given us.
Let me welcome Admiral Watkins. It is always a pleasure to
have him back because we have followed his thoughts on ocean
policies for some time. I look forward to the testimony.
Thank you very much.
Senator Cantwell. Thank you, Senator Stevens.
Senator Klobuchar?
STATEMENT OF HON. AMY KLOBUCHAR,
U.S. SENATOR FROM MINNESOTA
Senator Klobuchar. Thank you, Madam Chair. Thank you for
all of you coming. I am the Senator from Minnesota. I am the
only member of the Committee without an ocean. But I am pleased
to be here, of course, because of the Great Lakes and how
important that is to our way of life in Minnesota, with Lake
Superior, as well as our economy in Minnesota. I will tell you
that the lake levels in the Great Lakes continue to drop and we
are seeing an impact on the economy.
We are also seeing an impact of climate change on our
10,000 lakes that we are so proud of in Minnesota. That is what
our license plate says and it is something we are proud of. But
we have fishermen who cannot put their icehouses out for a
month. We have all kinds of issues that are coming up with our
wetlands.
So I look forward to hearing from this panel and thank you
for coming today.
Senator Cantwell. With that, we will go ahead and get
started with our witnesses. Mr. Doney, you are first. As I
said, I think we are asking people if they could keep their
comments to 5 minutes, knowing that some of you who have slide
presentations might take a little longer just to get through
that. But thank you very much for being here.
STATEMENT OF SCOTT C. DONEY, Ph.D., SENIOR SCIENTIST,
DEPARTMENT OF MARINE CHEMISTRY AND GEOCHEMISTRY, WOODS HOLE
OCEANOGRAPHIC INSTITUTION
Dr. Doney. Thank you. Good morning, Madam Chair, Ranking
Member Stevens, and other members of the Subcommittee. My name
is Scott Doney and I am a Senior Scientist at the Woods Hole
Oceanographic Institution, and I want to thank you--for the
opportunity to talk to you about ocean acidification and
climate change.
There is a broad U.S. scientific consensus that human
activities are increasing atmospheric carbon dioxide, altering
our planet's climate and acidifying the ocean. Climate change
and acidification will increasingly impact fisheries, coral
reefs, coastal environments, and the important economic and
ecosystem functions delivered by the ocean. We have an
opportunity to limit the negative impacts of ocean
acidification and climate change, but only if we take
deliberate and immediate action.
Atmospheric carbon dioxide has increased by 35 percent over
the last 2 centuries, mostly due to fossil fuel combustion.
Carbon dioxide is a greenhouse gas that traps heat near the
Earth's surface. Climate processes amplify the impact of
elevated carbon dioxide and other greenhouse gases and lead to
warming of the land and the ocean, melting of glaciers, retreat
of sea ice, and rising sea level.
Global warming should really be called ocean warming, as
more than 80 percent of the increased heat actually ends up in
the ocean. Measurements show that ocean warming is extending
from the surface down to a depth of at least 10,000 feet and
over the last several decades there has been a retreat of
Arctic sea ice by 15 to 20 percent over the summer and some
models predict that we will have ice-free conditions in the
Arctic by the year 2040.
But warming is not the only impact of carbon dioxide.
Elevated carbon dioxide also alters ocean chemistry. The ocean
absorbs about one-third of fossil fuel carbon emissions and
once in the ocean carbon dioxide combines with water to form an
acid, leading to more acidic conditions. The physical chemistry
of this process is well known and well understood.
Climate change and ocean acidification are confirmed by
real world observations and are supported by both models and
theory. Unless greenhouse gas emissions are curbed, these
trends will only accelerate over the next several decades.
Atmospheric carbon dioxide is already higher than at any time
in the last half million years and may double again in
concentration by the end of this century.
Warming and acidification affect ocean plants and animals
both directly and via changes in the ecosystems which they
depend upon for food and habitat. Some broad trends can be
identified. These include reduced biological productivity in
low and mid latitudes, polar shifts in warm-water species, and
declines in corals and other shell-forming plants and animals.
From historical data we know that commercially important
species such as salmon are sensitive to climate-driven changes
in the base of the ocean food chain. Of particular concern is
if there are climatic tipping points in the future that may
induce rapid and dramatic alterations in ocean ecosystems. My
fellow panelists will discuss in more detail some of the
changes we are already seeing and what we might expect to see
in the future.
For fisheries, climate and acidification impacts will
likely exacerbate other problems, including overfishing,
pollution, excess nutrients, and habitat destruction. Marine
life has survived large variations in the past, but the current
rates of climate change and ocean acidification are much faster
than experienced in most of geological history. The reality of
climate change and ocean acidification is now clear. Less clear
is the total extent of the repercussions that we face.
First and foremost, we need to control and reduce the
emissions of carbon dioxide and other greenhouse gases that are
the root of the problem.
Second, we need enhanced investment in an effort to monitor
ocean changes, understand biological responses, and convey this
information to stakeholders.
Third and finally, we need a comprehensive ocean management
strategy that explicitly addresses the need to adapt to climate
change and acidification that are now unavoidable.
Thank you for giving me this opportunity to address the
Subcommittee and I look forward to your questions.
[The prepared statement of Dr. Doney follows:]
Prepared Statement of Scott C. Doney, Ph.D., Senior Scientist,
Department of Marine Chemistry and Geochemistry, Woods Hole
Oceanographic
Institution \1\
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\1\ The views expressed here do not necessarily represent those of
the Woods Hole Oceanographic Institution.
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Introduction
Good morning Madame Chair, Ranking Member Snowe and members of the
Subcommittee. Thank you for giving me the opportunity to speak with you
today on global climate change, ocean acidification and the resulting
impacts on fisheries and living marine resources. My name is Scott
Doney, and I am a Senior Scientist at the Woods Hole Oceanographic
Institution in Woods Hole, Massachusetts. My research focuses on
interactions among climate, the ocean and global carbon cycles, and
marine ecosystems. I have published more than 90 peer-reviewed
scientific journal articles and book chapters on these and related
subjects. I serve on the U.S. Carbon Cycle Science Program Scientific
Steering Group and the U.S. Community Climate System Model Scientific
Steering Committee, and I am Chair of the U.S. Ocean Carbon and Climate
Change Scientific Steering Group and the U.S. Ocean Carbon and
Biogeochemistry Scientific Steering Committee.
For today's hearing, you have asked me to discuss the mechanisms by
which greenhouse gases impact the ocean, coastal environment, and
living marine resources, gaps in our current scientific understanding,
and implications for resource management including adaptation and
mitigation strategies. My comments are based on a broad scientific
consensus as represented in the current scientific literature and in
community assessments such as the 2007 Intergovernmental Panel on
Climate Change (IPCC) reports (IPCC, 2007a; 2007b; 2007c).
Over the past two centuries, human activities have resulted in
dramatic increases in atmospheric carbon dioxide and other greenhouse
gases. There is broad scientific consensus that these excess greenhouse
gases are altering our planet's climate and acidifying the ocean. These
findings are confirmed by real-world observations and supported by
theory and numerical models. Climate change and acidification trends
will accelerate over the next several decades unless there is
deliberate action to curb greenhouse emissions. Rising atmospheric
carbon dioxide and climate change produce upper-ocean warming, sea-ice
retreat, sea-level rise, ocean acidification, altered freshwater
distributions, and maybe even stronger storms.
Growing evidence suggests that these human-driven climate change
and acidification will strongly impact ocean ecosystems as well.
Further pressure will be put on living marine resources, such as
fisheries and coral reefs that we depend upon for food, tourism and
other economic and aesthetic benefits. We have an opportunity now to
limit the negative impact of climate change and acidification in the
future. This will require a comprehensive ocean management strategy
that incorporates scientific understanding of climate change and
acidification from the start. This strategy will also require a balance
between adaptation to climate change and acidification that are
unavoidable, and mitigation to reduce the rise in greenhouse gases and
resulting impacts.
Greenhouse Gases and Climate Change
At the most basic level, the balance between incoming sunlight and
outgoing infrared radiation (i.e., heat) determines Earth's climate.
The greenhouse gas carbon dioxide (CO2) plays a key role by
absorbing infrared radiation and thus trapping heat near the Earth's
surface much like a blanket. Other trace greenhouse gases such as
methane (CH4), nitrous oxide (N2O), and
chlorofluorocarbons (CFCs) are also important to warming, equivalent to
about half of that from carbon dioxide, because molecule for molecule
they absorb more infrared radiation than carbon dioxide. Other factors
involved in human-driven climate change include aerosols and land
vegetation.
Over the last two centuries, atmospheric carbon dioxide has
increased by more than 30 percent, from 280 to 380 ppm (part per
million) by 2007. The main source is fossil-fuel combustion with
contributions from cement production, agriculture and deforestation.
Many economic and climate models predict atmospheric carbon dioxide
values as high as 700 to 1,000 ppm, about triple preindustrial levels,
by the end of the twenty-first century. The Earth has not experienced
carbon dioxide levels that high for the past several million years.
Other trace greenhouse gas levels are growing as well due to land-use,
agriculture and industrial practices. These greenhouse gases persist in
the atmosphere for years to decades, meaning that they will remain and
accumulate in the atmosphere, impacting the global climate for a long
time to come. In contrast, aerosols in the lower atmosphere are removed
on time-scales of a few days to weeks, and their climatic impacts,
mostly cooling, are concentrated near their sources.
Greenhouse gases dominate over other human-driven climate
perturbations, and the increased heating translates into changes in
climate properties such as surface temperature, rainfall, sea-level and
storm frequency and strength. The climate change resulting from an
increase in greenhouse gases can be amplified by other climate
processes. For example, ocean warming leads to a large retreat in
Arctic sea-ice, which further strengthens warming because the dark
water surface can then absorb more sunlight than the highly reflective
ice. The largest unknowns at present arise from cloud dynamics.
Numerical model climate projections for this century show global mean
surface temperature increasing, with a range of +1.1 to 6.4+ C (+2.0 to
11.5+ F) above late 20th century levels. This large temperature range
is somewhat misleading as a significant fraction of the variation
depends on human behavior, specifically how much carbon dioxide and
other gases we emit to the atmosphere in the future. The lowest
temperature projections occur only when emissions are reduced sharply
over the next few decades.
The largest projected temperature changes are concentrated over the
continents and at higher latitudes during the winter season, but some
level of warming will occur globally, over the ocean, and year-round.
Sea-level is estimated to rise due to thermal warming and melting
glaciers and ice sheets by an additional +0.18 to 0.59m (+0.6 to 1.9
feet) by 2,100. Many simulations suggest a general strengthening of the
water cycle, with increased precipitation in the tropics and high
latitudes, drier conditions in the subtropics, and an increased
frequency of extreme droughts and floods. Other common features of a
warmer climate are more El Nino-like conditions in the Equatorial
Pacific, a melt back of polar sea-ice and glaciers, and a slowdown in
the formation of ocean deep water at high latitudes.
The Changing Ocean Environment
Global warming should be called ocean warming, as more than 80
percent of the added heat resides in the ocean. Clear alterations to
the ocean have already been detected from observations. The magnitude
and patterns of these changes are consistent with an attribution to
human activities and not explained by natural variability alone. Global
average land and ocean surface temperatures increased at a rate of
about 0.2+ C/decade over the last few decades (Hansen et al., 2006),
and ocean temperatures down to 3,000 m (10,000 feet) depth are also on
the rise. Averages rates of sea-level rise over the last several
decades were 1.80.5 mm/y, with an even larger rate
(3.10.7 mm/y) over the most recent decade. Higher
precipitation rates are observed at mid to high latitude and lower
rates in the tropics and subtropics. Corresponding changes have been
measured in surface water salinities. One of the most striking trends
is the decline in Arctic sea-ice extent, particularly over the summer.
September Arctic ice-cover from 2002-2006 was 18 percent lower than
pre-1980 ice-cover (http://www.arctic.noaa.gov/detect/ice-
seaice.shtml), and some models predict near ice-free conditions by
2040. Recent studies of the Greenland ice sheet highlight an alarming
increase in surface melting over the summer, and percolation of that
melt water to the base of the ice sheet where the melt-water could
lubricate ice flow and potentially greatly accelerate ice loss and sea-
level rise. These new findings have not been full incorporated into
projected sea-level rise estimates, which thus may be underestimated.
Over half of human carbon dioxide emissions to the atmosphere are
absorbed by the ocean and land biospheres (Sarmiento and Gruber, 2002),
and the excess carbon absorbed by the ocean results in increased ocean
acidity. The physical and chemical mechanisms by which this occurs are
well understood. Once carbon dioxide enters the ocean, it combines with
water to form carbonic acid and a series of acid-base products,
resulting in a lowering of pH values. The amount and distribution of
human-generated carbon in the oceans are well determined from an
international ocean survey conducted in the late 1980s and early 1990s
(Sabine et al., 2004). The rate of ocean carbon uptake is controlled by
ocean circulation. Most of the excess carbon is found in the upper few
hundred meters of the ocean (upper 1,200 feet) and in high-latitude
regions, where cold dense waters sink into the deep ocean. Surface
water pH values have already dropped by about 0.1 pH units from
preindustrial levels and are expected to drop by an additional 0.14-
0.35 units by the end of the 21st century (Orr et al., 2005).
Climate Change and Ocean Acidification Impacts on Marine Ecosystems
Climate change and ocean acidification will exacerbate other human
influences on fisheries and marine ecosystems such as over-fishing,
habitat destruction, pollution, excess nutrients, and invasive species.
Thermal effects arise both directly, via effects of elevated
temperature and lower pH on individual organisms, and indirectly via
changes to the ecosystems on which they depend for food and habitat.
Acidification harms shell-forming plants and animals including surface
and deep-water corals, many plankton, pteropods (marine snails),
mollusks (clams, oysters), and lobsters (Orr et al., 2005). Many of
these organisms provide critical habitat and/or food sources for other
organisms. Emerging evidence suggests that larval and juvenile fish may
also be susceptible to pH changes. Marine life has survived large
climate and acidification variations in the past, but the projected
rates of climate change and ocean acidification over the next century
are much faster than experienced by the planet in the past except for
rare, catastrophic events in the geological record.
One concern is that climate change will alter the rates and
patterns of ocean productivity. Small, photosynthetic phytoplankton
grow in the well-illuminated upper ocean, forming the base of the
marine food web, supporting the fish stocks we harvest, and underlying
the biogeochemical cycling of carbon and many other key elements in the
sea. Phytoplankton growth depends upon temperature and the availability
of light and nutrients, including nitrogen, phosphorus, silicon and
iron. Most of the nutrient supply to the surface ocean comes from the
mixing and upwelling of cold, nutrient rich water from below. An
exception is iron, which has an important additional source from
mineral dust swept off the desert regions of the continents and
transported off-shore from coastal ocean sediments. The geographic
distribution of phytoplankton and biological productivity is determined
largely by ocean circulation and upwelling, with the highest levels
found along the Equator, in temperate and polar latitudes and along the
western boundaries of continents.
Key climate-plankton linkages arise through changes in nutrient
supply and ocean mixed layer depths, which affect the light
availability to surface phytoplankton. In the tropics and mid-
latitudes, there is limited vertical mixing because the water column is
stabilized by thermal stratification; i.e., light, warm waters overlie
dense, cold waters. In these areas, surface nutrients are typically
low, which directly limits phytoplankton growth. Climate warming will
likely further inhibit mixing, reducing the upward nutrient supply and
thus lowering biological productivity. The nutrient-driven productivity
declines even with warmer temperatures, which promote faster growth. At
higher latitudes, phytoplankton often have access to abundant nutrients
but are limited by a lack of sunlight. In these areas, warming and
reduced mixed layer depths can increase productivity.
A synthesis of climate-change simulations shows broad patterns with
declining low-latitude productivity, somewhat elevated high-latitude
productivity, and pole-ward migration of marine ecosystem boundaries as
the oceans warm; simulated global productivity increased by up to 8.0
percent (Sarmiento et al., 2004). While not definitive proof of future
trends, similar relationships of ocean stratification and productivity
have been observed in year to year variability of satellite ocean color
data, a proxy for surface phytoplankton (Beherenfeld et al., 2006);
satellite data for 1997-2005 from GeoEYE and NASA's Sea-Viewing Wide
Field-of-View Sensor (SeaWiFS) show that phytoplankton declined in the
tropics and subtropics during warm phases of the El Nino-Southern
Oscillation (ENSO) marked by higher sea surface temperatures and ocean
stratification. Ecosystem dynamics are complex and non-linear, however,
and new and unexpected phenomena may arise as the planet enters a new
warmer and unexplored climate state. Ocean nitrogen fixation, for
example, is concentrated in warm, nutrient poor surface waters, and it
may increase under future more stratified conditions, enhancing overall
productivity.
Changes in total biological productivity are only part of the
story, as most human fisheries exploit particular marine species, not
overall productivity. The distributions and population sizes of
individual species are more sensitive to warming and altered ocean
circulation than total productivity. Temperature effects arise through
altered organism physiology and ecological changes in food supplies and
predators. Warming and shifts in seasonal temperature patterns will
disrupt predator-prey interactions; this is especially important for
survival of juvenile fish, which often hatch at a particular time of
year and depend up on immediate, abundant source of prey. Temperature
changes will also alter the spread of diseases and parasites in both
natural ecosystems and marine aquaculture. Warming impacts will
interact and perhaps exacerbate other problems including over-fishing
and habitat destruction.
Food-web interactions are often complicated, and we should expect
that some species will suffer under climate change while others will
benefit. Broadly speaking though, warm-water species are expected to
shift poleward, which already appears to be occurring in some fisheries
(Brander, 2006). Biological transitions, however, may be abrupt rather
than smooth. Large-scale regime shifts have been observed in response
to past natural variability. Regime shifts involve wholesale
reorganizations of biological food-webs and can have large consequences
from plankton to fish, marine mammals and sea-birds. Thus, rather
subtle climate changes or ocean acidification may have the potential to
disrupt commercially important species for either fisheries or tourism.
Decadal time-scale regime shifts have been documented in the North
Pacific, and in the Southern Ocean observations show a large-scale
replacement of krill, a food source for mammals and penguin, by
gelatinous zooplankton called salps.
A number of other factors also need to be considered. Species that
spend part of their life-cycle in coastal waters will be impacted by
degradation of near-shore nursery environments, such as mangrove
forests, marshes and estuaries, because of sea-level rise, pollution
and habitat destruction. Rainfall and river flow perturbations will
alter coastal freshwater currents, affecting the transport of eggs and
larvae. Some of the largest fisheries around the world, for example off
Peru and west coast of Africa, occur because of wind-driven coastal
upwelling, which may be sensitive to climate change. Warming will
reduce gas solubility and thus increases the likelihood of low oxygen
or anoxia events already seen in some estuaries and coastal regions,
such as off the Mississippi River in the Gulf of Mexico.
Knowledge Gaps and Ocean Research Priorities
Accurate projections of climate change and ocean acidification
impacts on living marine resources hinge on several key questions: (1)
how will greenhouse gas and aerosol emissions and atmospheric
composition evolve in the future? (2) how sensitive are regional-scale
ocean physics and chemistry to these changes in atmospheric
composition? and (3) how will individual species and whole-ocean
ecosystems respond? Fossil fuels are deeply intertwined in the modern
global economy, and carbon dioxide emissions depend upon changing
social and economic factors that are not well known: global population,
per capita energy use, technological development, national and
international policy decisions, and deliberate climate mitigation
efforts. Future projections of atmospheric carbon dioxide levels are
also relatively sensitive to assumptions about the behavior of land and
ocean carbon sinks, which are expected to change due to saturation
effects and responses to the modified physical climate (Fung et al.,
2005). Climate change on local and regional scales is more relevant for
people and ecosystems than global trends. While progress is being made,
improved and better-validated regional ocean climate forecasts remain a
major need for future research.
Even when predictions about the physical environment are well
known, significant knowledge gaps exist about ocean ecology, hindering
the creation of the skillful forecasts needed to guide ocean management
decisions. While not precluding taking action now to address climate
change and ocean acidification, better scientific understanding will
help refine ocean management in the long-term. Several elements need to
be pursued in parallel: improved on-going monitoring of ocean climate
and biological trends; laboratory and field process studies to quantify
biological climate sensitivities; historical and paleoclimate studies
of past climate events; and incorporation of the resulting scientific
insights into an improved hierarchy of numerical ocean models from
species to ecosystems.
Rapid advances in in situ sensors and autonomous platforms, such as
moorings, floats and gliders, are revolutionizing ocean measurements,
and ocean observing networks are being constructed for coastal and open
ocean regions (e.g., Gulf of Maine Ocean Observing System http://
www.gomoos.org/; Pacific Coast Ocean Observing System http://
www.pacoos.org/; National Science Foundation Ocean Observing Initiative
http://www.ooi.org). The number of historical, multi-decadal ocean time
series is limited, but their scientific utility is almost unrivalled.
Federal commitment is needed for continued, long-term investment in
ocean monitoring and enhanced coordination across observing networks.
In a similar vein, satellite measurements provide an unprecedented
view of the temporal variations in ocean climate and ecology. The ocean
is vast, and the limited number of research ships move at about the
speed of a bicycle, too slow to map the ocean routinely on ocean basin
to global scales. By contrast, a satellite can observe the entire
globe, at least the cloud free areas, in a few days. The detection of
gradual climate-change trends is challenging, and the on-going
availability of high-quality, climate data records is not assured
during the transition of many satellite ocean measurements from NASA
research to the NOAA/DOD operational NPOESS program. For example, the
present NASA satellite ocean color sensors, needed to determine ocean
plankton, are nearing the end of their service life, and the
replacement sensors on NPOESS may not be adequate for the climate
community. Further, refocusing of NASA priorities away from Earth
science may dramatically limit or fully preclude new ocean satellite
missions needed to characterize ocean climate and biological dynamics.
We need to know if there are climatic tipping points or thresholds
beyond which climate change may induce rapid and dramatic regime shifts
in ocean ecosystems. Many current scientific studies examine climate
sensitivities of species in isolation; the next step involves examining
responses of species populations, communities of multiple interacting
species, and entire ecosystems to realistic size perturbations.
Experiments on plankton and benthic communities can be conducted under
relatively controlled conditions in mesocosms (large enclosed volumes
such as aquarium or floating bags deployed at sea) or by deliberate
open-water perturbations studies. Both approaches will benefit from
further directed technological developments. Larger mobile species
require different approaches such as using past climate events as
analogues for human-driven climate change. Biology models are pivotal
to ocean management. They are being improved progressively by
incorporating new information from laboratory and field experiments and
by comparing model forecasts with real-world data. It is often as
important to identify where the models do poorly as where they do well
because research can then be focused on resolving these model errors.
Climate Adaptation, Mitigation, and Ocean Management
Given the potential for significant negative impacts of climate
change and ocean acidification on living marine resources, we need to
develop comprehensive local, national and international ocean
management strategies that fully incorporate climate change and
acidification trends and uncertainties. The strategies should follow a
precautionary approach that accounts for the fact that ocean biological
thresholds are unknown. The strategies should include improved
scientific information for decision-support, adaptation to reduce
negative climate change and acidification impacts, and mitigation to
decrease the magnitude of future climate change and acidification.
Currently the United States and other countries invest significant
resources in monitoring the ocean and improving scientific
understanding on many of the physical, chemical and biological
processes relevant to climate change and acidification. However, this
wealth of data and information is typically not in a form that is
easily accessible by ocean resource managers and other stakeholders,
ranging from private citizens and small-businesses to large
corporations, NGO's and national governments. For example, even state-
of-the-art climate projections typically resolve climate patterns at
relatively coarse spatial resolutions and include either relatively
simple ocean biology or no ocean biology at all. In contrast,
decisionmakers need information tailored to specific local fisheries
and ecosystems. The national climate modeling centers should be
encouraged to create on a routine basis targeted ocean biological-
physical forecasts on seasonal to decadal time-scales, building on
nested regional models, probabilistic and ensemble modeling of
uncertainties, and downscaling methods developed for related
applications (e.g., agriculture, water-resources). The utility of such
forecasts and their uncertainties will be maximized if stakeholders are
involved in their design from the onset and if the model results are
translated into more accessible electronic forms that are widely
distributed to the public.
A second challenge is to create more adaptive ocean management
strategies that emphasize complete and transparent discussion on the
risks and uncertainties from climate change and ocean acidification.
Some amount of climate change and acidification is unavoidable because
of past greenhouse emissions, and even under relatively optimistic
scenarios for the future, substantial further ocean impacts should be
expected at least through mid-century and beyond. Decisions will need
to be made in the face of uncertainty, relying on for example the
precautionary principle to limit future risk. Climate change trends are
growing in magnitude, but will still be gradual compared with natural
interannual variability; management policies must include both types of
variations and uncertainties. Empirical approaches developed from
historical data cannot be used in isolation because climate change will
shift the baseline for ocean biological systems. Serious efforts should
be directed at reducing other human factors such as overfishing and
habitat destruction to allow more time for ecosystems and social
systems to adapt. Mechanisms such as marine reserves, that protect
specified geographical locations, need to account for the fact that
ecosystem boundaries will shift under climate change. Procedures also
need to be in place to monitor over time the effectiveness of ocean
conservation and management policies, and that information and improved
future climate forecasts should be used to modify and adapt management
approaches.
The third challenge is to pursue climate mitigation approaches that
limit the emissions of carbon dioxide and other greenhouse gases to the
atmosphere or that remove fossil-fuel carbon dioxide that is already in
the atmosphere. Stabilizing future atmospheric carbon dioxide at
moderate levels to minimize climate change impacts will require a mix
of approaches, and no single mechanism will solve the entire problem.
Emissions of carbon dioxide can be reduced through energy conservation
and transition to alternative, non-fossil fuel based energy sources
(wind, solar, nuclear, biofuels). Attention also needs to be placed in
the near-term on limiting other greenhouse gases such as
chlorofluorocarbons, which may provide additional time to tackle the
more challenging issues associated with carbon. Progress is being made
on approaches that would remove carbon dioxide at power plants so that
it can be sequestered in subsurface geological reservoirs (e.g., old
oil and gas fields, salt domes).
Mitigation approaches have also been proposed using ocean biology,
but these methods should only be pursued if critical questions are
resolved on their effectiveness and environmental consequences.
Biological mitigation strategies are based on the fact that plants and
some marine microbes naturally convert carbon dioxide into organic
matter during photosynthesis. Enhancing biological carbon removal can
reduce atmospheric carbon dioxide if the additional organic matter is
stored away from the atmosphere for multiple decades to a century or
longer. The deep-ocean is one such reservoir because it exchanges only
slowly with the surface and atmosphere. Thus one potential mitigation
method would be to fertilize the surface ocean phytoplankton so that
they produce and export more organic carbon into the deep ocean. In
many areas of the ocean, phytoplankton growth is limited by the trace
element iron, which is very low in surface waters away from continents
and dust sources. About a dozen scientific experiments have been
conducted successfully showing that adding iron to the surface ocean
causes a phytoplankton bloom and temporary drawdown in surface water
carbon dioxide. But there remain outstanding scientific questions about
whether iron resulted in any enhanced long-term carbon storage in the
ocean.
As with any other mitigation approach on land or in the sea, the
scientific and policy communities need to work closely to assure that
the following questions are answered for large-scale commercial ocean
fertilization. Is the method effective in removing carbon from the
atmosphere, can the removal be validated, and how long will it remain
sequestered? Could the method result in unintended consequences such as
enhanced emissions of other, more powerful greenhouse gases (in the
case of iron fertilization potentially nitrous oxide and perhaps
methane)? What are the broad ecological consequences, and could carbon
mitigation efforts conflict with maintaining living marine resources
and fisheries? Systematic approaches to verify effectiveness and
environmental impacts need to be put in place to assure a level playing
field for commercial mitigation and carbon credit trading systems.
Conclusions
Over the past two centuries, human activities have resulted in the
buildup in the atmosphere of excess carbon dioxide, other greenhouse
gases and aerosols. There is now significant evidence that these
changes in atmospheric composition are altering the planet's climate.
Human-driven climate change is expected to accelerate over the next
several decades, leading to extensive global warming, sea-ice retreat,
sea-level rise, ocean acidification, and alterations in the freshwater
cycle. As the reality of climate change is becoming clearer, the
emphasis shifts toward understanding the impact of these climate
perturbations on society and on natural and managed ecosystems.
Marine fisheries and ocean ecosystems are susceptible to global
warming and ocean acidification. While ocean biological responses will
vary from region to region, some broad trends can be identified
including poleward shifts in warm-water species and reduced formation
of calcium carbonate by corals and other shell-forming plants and
animals. For fisheries, climate change impacts will interact and
perhaps exacerbate other problems including over-fishing and habitat
destruction. Management strategies are needed balancing adaptation to
an evolving climate and mitigation to reduce the magnitude of future
climate change and atmospheric carbon dioxide growth. Decision support
tools should be developed for marine resource managers that incorporate
the emerging scientific understanding on climate change, focusing on
impacts over the next several decades. Systematic testing is required
on the effectiveness and environmental consequences of climate
mitigation approaches, such as deliberate iron fertilization, designed
to sequester additional carbon in the ocean.
Thank you for giving me this opportunity to address this
Subcommittee, and I look forward to answering your questions.
Selected References
Brander, K. (2006) Assessment of Possible Impacts of Climate Change
on Fisheries. Externe Expertise fur das WBGU-Sondergutachten ``Die
Zukunft der Meere--zu warm, zu hoch, zu sauer,'' Berlin WBGU, 27 pp.
Fung, I., S.C. Doney, K. Lindsay, and J. John, 2005: Evolution of
carbon sinks in a changing climate, Proc. Nat. Acad. Sci. (USA), 102,
11201-11206, doi: 10.1073/pnas.0504949102.
Hansen, J., M. Sato, R. Ruedy, K. Lo, D.W. Lea, and M. Medina-
Elizade, 2006: Global temperature change, Proc. Nat. Acad. Sci. USA,
103, 14288-14293, 10.1073/pnas.0606291103.
IPCC, (2007a) The Physical Science Basis, Summary for Policymakers,
Contributions of Working Group I to the Fourth Assessment Report of the
Intergovernmental Panel on Climate Change, 18 pp., (http://www.ipcc.ch/
).
IPCC, (2007b) Impacts, Adaptation and Vulnerability, Summary for
Policymakers, Contributions of Working Group II to the Fourth
Assessment Report of the Intergovernmental Panel on Climate Change,
22pp., (http://www.ipcc.ch/).
IPCC, (2007c) Mitigation of Climate Change, Summary for
Policymakers, Contributions of Working Group III to the Fourth
Assessment Report of the Intergovernmental Panel on Climate Change, 36
pp., (http://www.ipcc.ch/).
Orr, J.C., V.J. Fabry, O. Aumont et al., (2005) Anthropogenic ocean
acidification over the twenty-first century and its impact on marine
calcifying organisms, Nature, 437, 681-686, doi: 10.1038/nature04095.
Sabine, C.L., R.A. Feely, N. Gruber et al., (2004) The oceanic sink
for anthropogenic CO2, Science, 305, 367-371.
Sarmiento, J.L. and N. Gruber (2002) Sinks for anthropogenic
carbon, Physics Today, August, 30-36.
Sarmiento, J.L., et al., (2004) Response of ocean ecosystems to
climate warming, Global Biogeochem. Cycles, 18, GB3003, doi: 10.1029/
2003GB002134.
Senator Cantwell. Thank you very much.
Dr. Feely, thank you very much for being here. We are very
proud, obviously, of the Pacific Marine Environmental
Laboratory in the Northwest and we appreciate you being here as
NOAA's representative today.
STATEMENT OF RICHARD A. FEELY, Ph.D., SUPERVISORY
CHEMICAL OCEANOGRAPHER, PACIFIC MARINE
ENVIRONMENTAL LABORATORY, NOAA,
U.S. DEPARTMENT OF COMMERCE
Dr. Feely. Thank you very much. Good morning, Madam Chair
Cantwell, Ranking Member Stevens, and members of the
Subcommittee. My name is Richard Feely and I am a Supervisory
Oceanographer at NOAA's Pacific Marine Environmental Laboratory
in Seattle. Part of NOAA's mission is to understand and predict
changes in Earth's environment. My area of expertise and the
focus of my research is that of the study of the ocean's carbon
cycle and its effect on marine life. Thank you for inviting me
today to provide my insights on ocean acidification and its
effects on living marine resources.
Over the past 200 years the release of carbon dioxide from
our collective industrial and agricultural activities has
resulted in atmospheric CO2 concentration increases
of about 100 parts per million. During this period the oceans
have absorbed 525 billion tons of carbon dioxide from the
atmosphere. This is about one-third of human-generated carbon
dioxide emissions. The oceans' daily uptake of 22 million tons
of carbon dioxide is now starting to have a significant impact
on the chemistry and biology of the oceans.
Hydrographic surveys and modeling studies reveal the
chemical changes that have taken place. We see change in the
lowering of the pH. This pH is a measure of the acidity and the
acidity of our oceans has changed by 30 percent since the
beginning of the Industrial Revolution. Our projections through
the end of the century suggest that the acidity may change by
as much as 150 percent if we follow CO2 emissions
scenarios based on the IPCC IS92a projections.
This process of acidification of the oceans is causing a
lowering of the carbonate ion concentration levels as well. The
carbonate ion plays an important role in shell formation for a
number of marine organisms, such as corals, marine plankton,
and shellfish. Many marine organisms which use carbonate ions
to produce calcium carbonate shells experience detrimental
effects due to these increasing CO2 levels.
For example, ocean acidification is shown to significantly
affect coral reefs. It reduces the ability of rebuilding corals
to produce their skeletons, affecting growth of individual
corals and making the reefs more vulnerable to erosion. Some
estimates indicate that by the end of this century coral reefs
may erode faster than they can be rebuilt. This could
compromise the long-term viability of these ecosystems and
perhaps affect the thousands of species that depend on this
particular habitat.
In long-term experiments, corals grown under the most
acidic conditions for periods more than 1 year have not shown
the ability to adapt their calcification rates to these higher
CO2 levels. In fact, a recent study has shown that
projected CO2 increase in the oceans is sufficient
to dissolve the calcium carbonate skeletons of some coral reef
species.
Ongoing research has shown that the increase in acidity may
have deleterious impacts on commercially important fish and
shellfish larvae. Both king crab and silver seabream larvae
exhibit a very high mortality rate in CO2-rich
waters. The calcification rates of the edible mussel and
Pacific oyster of the Pacific Northwest region decline linearly
with increasing CO2 levels. Squid are especially
sensitive to ocean acidification because it directly affects
their blood oxygen transport and respiration. Scientists have
been seeing a reduced ability of marine algae, free-floating
plants and animals to produce their protective calcium
carbonate shells.
One of these free-swimming mollusks is called a pteropod.
Pteropods are eaten by organisms ranging from krill to whales
and are a major food source for North Pacific juvenile salmon
and serve as food for mackerel, pollock, herring, and cod.
Ocean acidification is one of the most significant and far-
reaching consequences of the buildup of human-generated carbon
dioxide in the atmosphere and the oceans. Results from
laboratory, field, and modeling studies, as well as evidence
from the geological record, clearly indicate that many
ecosystems are highly susceptible to changes in ocean
CO2 and the corresponding decrease in pH and
increase in acidity. Because of the very clear potential for
ocean-wide effects of ocean acidification at all levels of the
marine ecosystem from the tiniest phytoplankton to the
zooplankton to fish and shellfish, we can expect to see
significant effects that are immensely important for mankind.
Ocean acidification is an emerging scientific issue and
much research is needed before all the species and ecosystem
responses are well understood. However, to the limit that the
scientific community understands this issue right now, the
potential for environmental, economic, and societal risk is
quite high. Ocean acidification demands serious and immediate
attention.
For these reasons, the national and technological
scientific communities have recommended a coordinated research
program with four major themes: carbon system monitoring,
calcification and physiological response studies under both
laboratory and field conditions, environmental and ecosystem
modeling studies, and socioeconomic risk assessments. This
research will provide resource managers with the basic
information they need to develop strategies for protection of
species, habitats, and ecosystems.
I am deeply grateful for the opportunity to discuss this
issue with you and look forward to answering your questions.
[The prepared statement of Dr. Feely follows:]
Prepared statement of Richard A. Feely, Ph.D., Supervisory Chemical
Oceanographer, Pacific Marine Environmental Laboratory, NOAA,
U.S. Department of Commerce
Introduction
Good morning, Chairman Cantwell and members of the Subcommittee.
Thank you for giving me the opportunity to speak with you today on the
short- and long-term impacts of ocean acidification on marine
resources. My name is Richard Feely, I am a Supervisory Chemical
Oceanographer at the Pacific Marine Environmental Laboratory of the
National Oceanic and Atmospheric Administration (NOAA) in Seattle, WA.
My personal area of research is the study of the oceanic carbon cycle
and its impact on marine organisms. I have worked for NOAA for more
than 32 years and have published more than 160 peer-reviewed scientific
journal articles, book chapters and technical reports. I serve on the
U.S. Carbon Cycle Science Program Scientific Steering Group and I am
the co-chair of the U.S. Repeat Hydrography Program Scientific
Oversight Committee. For today, you have asked me to provide my
insights on ocean acidification and its effect on living marine
ecosystems. Most of my comments below are derived from the Royal
Society Report, ``Ocean Acidification Due to Increasing Atmospheric
Carbon Dioxide'' (Raven et al., 2005) and the recent U.S. report,
derived from a workshop held jointly by the National Science Foundation
(NSF), NOAA, and the U.S. Geological Survey, entitled ``Impacts of
Ocean Acidification on Coral Reefs and Other Marine Calcifiers `'
(Kleypas et al., 2006).
Ocean Acidification
Over the past 200 years the release of carbon dioxide
(CO2) from our collective industrial and agricultural
activities has resulted in atmospheric CO2 concentrations
that have increased by about 100 parts per million (ppm). The
atmospheric concentration of CO2 is now higher than
experienced on Earth for at least the last 800,000 years, and is
expected to continue to rise, leading to significant temperature
increases in the atmosphere and oceans by the end of this century. The
oceans have absorbed approximately 525 billion tons of carbon dioxide
from the atmosphere, or about one-third of the anthropogenic carbon
emissions released during this period (Sabine and Feely, 2007). This
natural process of absorption has benefited humankind by significantly
reducing the greenhouse gas levels in the atmosphere and minimizing
some of the impacts of global warming. However, the ocean's daily
uptake of 22 million tons of carbon dioxide is starting to have a
significant impact on the chemistry and biology of the oceans. For more
than 25 years, NOAA and NSF have co-sponsored repeat hydrographic and
chemical surveys of the world oceans, documenting the ocean's response
to increasing amounts of carbon dioxide being emitted to the atmosphere
by human activities. These surveys have confirmed that the oceans are
absorbing increasing amounts of carbon dioxide. Both the hydrographic
surveys and modeling studies reveal that the chemical changes in
seawater resulting from the absorption of carbon dioxide are lowering
seawater pH (Feely et al., 2004; Orr et al., 2005; Caldeira and
Wickett, 2005; Feely et al., in press). It is now well established that
the pH of our ocean surface waters has already fallen by about 0.1
units from an average of about 8.21 to 8.10 since the beginning of the
Industrial Revolution (on the logarithmic pH scale, 7.0 is neutral
(e.g., water), with points higher on the scale being ``basic'' and
points lower being ``acidic.''). Estimates of future atmospheric and
oceanic carbon dioxide concentrations, based on the Intergovernmental
Panel on Climate Change (IPCC) CO2 emission scenarios and
general circulation models, indicate that by the middle of this century
atmospheric carbon dioxide levels could reach more than 500 parts per
million (ppm), and near the end of the century they could be over 800
ppm. This would result in a surface water pH decrease of approximately
0.4 pH units as the ocean becomes more acidic, and the carbonate ion
concentration would decrease almost 50 percent by the end of the
century (Orr et al., 2005). To put this in historical perspective, this
surface ocean pH decrease would result in a pH that is lower than it
has been for more than 20 million years (Feely et al., 2004). When
CO2 reacts with seawater, fundamental chemical changes occur
that cause a reduction in seawater pH. The interaction between
CO2 and seawater also reduces the availability of carbonate
ions, which play an important role in shell formation for a number of
marine organisms such as corals, marine plankton, and shellfish. This
phenomenon, which is commonly called ``ocean acidification,'' could
affect some of the most fundamental biological and geochemical
processes of the sea in coming decades. This rapidly emerging issue has
created serious concerns across the scientific and fisheries resource
management communities.
Effects of Ocean Acidification on Coral Reefs
Many marine organisms that produce calcium carbonate shells studied
thus far have shown detrimental effects due to increasing carbon
dioxide levels in seawater and the resulting decline in pH. For
example, increasing ocean acidification has been shown to significantly
reduce the ability of reef-building corals to produce their skeletons,
affecting growth of individual corals and making the reef more
vulnerable to erosion (Kleypas et al., 2006). Some estimates indicate
that, by the end of this century, coral reefs may erode faster than
they can be rebuilt. This could compromise the long-term viability of
these ecosystems and perhaps impact the thousands of species that
depend on the reef habitat. Decreased calcification may also compromise
the fitness or success of these organisms and could shift the
competitive advantage toward organisms that are not dependent on
calcium carbonate. Carbonate structures are likely to be weaker and
more susceptible to dissolution and erosion. In long-term experiments
corals that have been grown under lower pH conditions for periods
longer than 1 year have not shown any ability to adapt their
calcification rates to the low pH levels. In fact, a recent study
showed that the projected increase in CO2 is sufficient to
dissolve the calcium carbonate skeletons of some coral species (Fine
and Tchernov, 2007).
Effects of Ocean Acidification on Fish and Shellfish
Ongoing research is showing that decreasing pH may also have
deleterious effects on commercially important fish and shellfish
larvae. Both king crab and silver seabream larvae exhibit very high
mortality rates in CO2-enriched waters (Litzow et al.,
submitted; Ishimatsu et al., 2004). Some of the experiments indicated
that other physiological stresses were also apparent. Exposure of fish
to lower pH levels can cause decreased respiration rates, changes in
blood chemistry, and changes in enzymatic activity. The calcification
rates of the edible mussel (Mytilus edulis) and Pacific oyster
(Crassostrea gigas) decline linearly with increasing CO2
levels (Gazeau et al., in press). Squid are especially sensitive to
ocean acidification because it directly impacts their blood oxygen
transport and respiration (Portner et al., 2005). Sea urchins raised in
lower-pH waters show evidence for inhibited growth due to their
inability to maintain internal acid-base balance (Kurihara and
Shirayama., 2004). Scientists have also seen a reduced ability of
marine algae and free-floating plants and animals to produce protective
carbonate shells (Feely et al., 2004; Orr et al., 2005). These
organisms are important food sources for other marine species. One type
of free-swimming mollusk called a pteropod is eaten by organisms
ranging in size from tiny krill to whales. In particular, pteropods are
a major food source for North Pacific juvenile salmon, and also serve
as food for mackerel, pollock, herring, and cod. Other marine
calcifiers, such as coccolithophores (microscopic algae), foraminifera
(microscopic protozoans), coralline algae (benthic algae), echinoderms
(sea urchins and starfish), and mollusks (snails, clams, and squid)
also exhibit a general decline in their ability to produce their shells
with decreasing pH (Kleypas et al., 2006).
Effects on Marine Ecosystems
Since ocean acidification research is still in its infancy, it is
impossible to predict exactly how the individual species responses will
cascade throughout the marine food chain and impact the overall
structure of marine ecosystems. It is clear, however, from the existing
data and from the geologic record that some coral and shellfish species
will be reduced in a high-CO2 ocean. The rapid disappearance
of many calcifying species in past extinction events has been
attributed, in large part, to ocean acidification events (Zachos et
al., 2005). Over the next century, if CO2 emissions are
allowed to increase as predicted by the IPCC CO2 emissions
scenarios, mankind may be responsible for increasing oceanic
CO2 and making the oceans more corrosive to calcifying
organisms than anytime since the last major extinction, over 65 million
years ago. Thus, the decisions we make about our use of fossil-fuels
for energy over the next several decades will probably have a profound
influence on makeup of future marine ecosystems for centuries to
millennia.
Economic Impacts
The impact of ocean acidification on fisheries and coral reef
ecosystems could reverberate through the U.S. and global economy. The
U.S. is the third largest seafood consumer in the world with total
consumer spending for fish and shellfish around $60 billion per year.
Coastal and marine commercial fishing generates upwards of $30 billion
per year and employs nearly 70,000 people (NOAA Fisheries Office of
Science and Technology; http://www.st.nmfs.gov/st1/fus/fus05/
index.html). Nearly half of the U.S. fishery is derived from the
coastal waters surrounding Alaska. Increased ocean acidification may
directly or indirectly influence the fish stocks because of large-scale
changes in the local ecosystem dynamics. It may also cause the
dissolution of the newly discovered deepwater corals in the Alaskan
Aleutian Island region. Many commercially important fish species in
this region depend on this particular habitat for their survival.
Healthy coral reefs are the foundation of many viable fisheries, as
well as the source of jobs and businesses related to tourism and
recreation. In the Florida Keys, coral reefs attract more than $1.2
billion in tourism annually. In Hawaii, reef-related tourism and
fishing generate $360 million per year, and their overall worth has
been estimated at close to $10 billion. In addition, coral reefs
provide vital protection to coastal areas that are vulnerable to storm
surges and tsunamis.
Conclusions
Ocean acidification may be one of the most significant and far-
reaching consequences of the buildup of anthropogenic carbon dioxide in
the atmosphere. Results from laboratory, field and modeling studies, as
well as evidence from the geological record, clearly indicate that
marine ecosystems are highly susceptible to the increases in oceanic
CO2 and the corresponding decreases in pH. Corals and other
calcifying organisms will be increasingly affected by a decreased
capability to produce their shells and skeletons. Other species of fish
and shellfish will also be negatively impacted in their physiological
responses due to a decrease in pH levels of their cellular fluids.
Because of the very clear potential for ocean-wide impacts of ocean
acidification at all levels of the marine ecosystem, from the tiniest
phytoplankton to zooplankton to fish and shellfish, we can expect to
see significant impacts that are of immense importance to mankind.
Ocean acidification is an emerging scientific issue and much research
is needed before all of the ecosystems responses are well understood.
However, to the limit that the scientific community understands this
issue right now, the potential for environmental, economic and societal
risk is also quite high, hence demanding serious and immediate
attention. For these reasons, the national and international scientific
communities have recommended a coordinated scientific research program
with four major themes; (1) carbon system monitoring; (2) calcification
and physiological response studies under laboratory and field
conditions; (3) environmental and ecosystem modeling studies; and (4)
socioeconomic risk assessments. This research will provide resource
managers with the basic information they need to develop strategies for
protection of critical species, habitats and ecosystems, similar to
what has already been developed for coral reef managers with the
publication of the Reef Manager's Guide by the U.S. Coral Reef Task
Force to help local and regional reef managers reduce the impacts of
coral bleaching to coral reef ecosystems.
Thank you for giving me this opportunity to address this
Subcommittee. I look forward to answering your questions.
Selected References
Caldeira, K., and M.E. Wickett, Ocean model predictions of
chemistry changes from carbon dioxide emissions to the atmosphere and
ocean. Journal of Geophysical Research (Oceans) 110, C09S04, doi:
10.1029/2004JC002671, 2005.
Feely, R.A., C.L. Sabine, K. Lee, W. Berrelson, J. Kleypas, V.J.
Fabry, and F.J. Millero, 2004, Impact of anthropogenic CO2
on the CaCO3 system in the oceans, Science, 305(5682): 362-
366.
Feely, R.A., J. Orr, V.J. Fabry, J.A. Kleypas, C.L. Sabine, and C.
Landgon (in press): Present and future changes in seawater chemistry
due to ocean acidification. AGU Monograph on ``The Science and
Technology of Carbon Sequestration''.
Fine, M. and D. Tchernov (2007). Scleractinian coral species
survive and recover from decalcification, Science (315): 1811.
Gazeau, F., Quiblier, C., Jeroen M. Jansen, J.M. Jean-Pierre
Gattuso, J.-P., Middelburg, J.J., and C. H.R. Heip (in press) Impact of
elevated CO2 on shellfish calcification, Geophysical
Research Letters.
Ishimatsu, A., Kikkawa, T., Hayashi, M., Lee, K.-S., and J. Kita
(2004): Effects of CO2 on marine fish: Larvae and adults,
Journal of Oceanography, Vol. 60, pp. 731-741.
Kleypas, J.A., R.A. Feely, V.J. Fabry, C. Langdon, C.L. Sabine, and
L.L. Robbins (2006): Impacts of ocean acidification on coral reefs and
other marine calcifiers: A guide to future research. Report of a
workshop held 18-20 April 2005, St. Petersburg, FL, sponsored by NSF,
NOAA, and the U.S. Geological Survey, 88 pp.
Kurihara, K. and Shirayama, Y. (2004): Impacts of increased
atmospheric CO2 on sea urchin early development, Mar. Ecol;.
Prog. Ser., 274, 161-169.
Marshall, P. and H. Schuttenberg (2006): A Reef Manager's Guide to
Coral Bleaching, Great Barrier Ref Marine Park Authority, Townsville,
Australia, 139 pp.
Michael A., Litzow, M.A., Short, J.W., J.W. , Persselin, S.L., Lisa
A. Hoferkamp3, L.A. and S.A. Payne, (submitted for publication).
Calcite undersaturation reduces larval survival in a crustacean,
Science.
Orr, J.C., V.J. Fabry, O. Aumont, L. Bopp, S.C. Doney, R.A. Feely,
A. Gnanadesikan, N. Fruber, A. Ishida, F. Joos, R.M. Key, K. Lindsay,
E. Maier-Reimer, R. Matear, P. Monfray, A. Mouchet. R.G. Najjar, G.-K.
Plattner, K.B. Rodgers, C.L. Sabine, J.L. Sarmiento, R. Schlitzer, R.D.
Slater, I.J. Totterdel, M.-F. Weirig, Y. Yamanaka, and A. Yool, 2005,
Anthropogenic ocean acidification over the twenty-first century and its
impact on calcifying organisms, Nature, 437: 681-686.
Portner, H.O., M. Langenbuch, and B. Michaelidis (2005) Synergistic
effects of temperature extremes, hypoxia, and increases in
CO2 on marine animals: From Earth history to global change,
J. Geophys. Res. 110, C09S10, doi: 10.1029/2004JC002561.
Raven, J. Caldeira, K. Elderfield, H. Hoegh-Guldberg, O. Liss, P.
Riebesell, U. Shepherd, J. Turley, C. Watson, A. (2005) Acidification
due to increasing carbon dioxide. In Report 12/05. London, T.R.S.o.
(ed.) London: The Royal Society, pp. vii + 60.
Zachos, J.C., U. Rohl, S.A. Schellenberg, A. Sluijs, D.A. Hodell,
D.C. Keely, E. Thomas, M. Nicolo, I. Raffi, L.J. Lourens, H. McCarren,
and D. Kroon, 2005, Rapid acidification of the ocean during the
Paleocene-Eocene thermal maximum, Science, 308: 1611-16.
Senator Cantwell. Thank you very much.
Dr. Conover?
STATEMENT OF DAVID O. CONOVER, Ph.D., DEAN
AND DIRECTOR, MARINE SCIENCE RESEARCH CENTER,
STONY BROOK UNIVERSITY
Dr. Conover. Good morning, Chair Cantwell, Ranking Member
Stevens, and members of the Subcommittee. My name is David
Conover. I am a fisheries scientist and I also serve as Dean of
Marine and Atmospheric Sciences at Stony Brook University on
Long Island, New York. I am mostly going to talk about the
effect of ocean warming on fisheries.
I have studied the ecology of marine fishes along the U.S.
East Coast for over 30 years. My message is this. We already
see strong evidence of the effects of ocean warming on fish and
shellfish along the East Coast. The evidence includes declines
in cold-water species due to heat stress and disease, northward
expansion of southern species, and explosions of invasive
species. Let me explain what is going on.
Because most animals in the sea are cold-blooded, ocean
temperature has an enormous direct impact on their biology. We
know a lot about the direct thermal effects at the species
level, less so at the ecosystem level. But we know enough to
make strong predictions.
All species are adapted for life over a relatively narrow
range of temperatures. Some species like it warm, others like
it cold. Certain regions of the world ocean, particularly the
East Coast, have transition zones between cold-water and warm-
water habitats. That is where you are going to first see the
impacts of warming. My home state of New York sits right in the
middle of a transition zone. We are the southern end point for
northern species like cod, herring, and American lobsters and
we are at the northern end point for southern species like
weakfish, fluke, and bluefish.
Here is what we see happening in New York. In 1999, we had
a massive summer die-off of lobsters in Long Island Sound,
followed by continued summer mortality in subsequent years. The
probability is that lobsters cannot tolerate the exceptionally
warm summer temperatures we have been having. Heat stress leads
to physiological, pathogenic, and parasitic diseases. The
result has been an 85 percent reduction in landings, and these
diseases now appear to be moving northward.
Another example is a parasitic disease called dermo. It
causes catastrophic mortality of oysters. Prior to 1990, this
parasite was unknown north of Chesapeake Bay. In the 1990s
dermo underwent a massive northward range expansion, extending
all the way into the Gulf of Maine. The expansion occurred
during years when winters were unusually warm. Dermo is now
highly prevalent from Delaware Bay to Cape Cod, with no signs
of abating.
Winter flounder is another species at the southern end of
its range in New York. It too is declining drastically in our
area. Commercial landings in New York are only 15 percent of
what they were a few years ago. And it is not just winter
flounder. When you look at the fin fish community of Long
Island Sound as a whole over the last 15 years, nearly all of
the cold-water species have been declining and nearly all of
the warm-water species are increasing.
Finally, there is the problem of invasive species. The
recent trend of warmer winters in Long Island Sound has favored
the growth and recruitment of exotic species over natives.
Invasive sea squirts that like winters that are warm are
coating the bottom of Long Island Sound, driving away native
species.
What do we do about this? From a fishery management
perspective, we need to recognize that harvested populations
near the limits of their ranges will need extra precautionary
measures to protect them from extinction. Predators, pathogens,
parasites and invasive species are moving across ecosystem
boundaries. We may need to reduce harvest of some of these
species in certain areas to enable them to withstand additional
stress.
Of course, the ultimate and best solution is the reduction
of greenhouse gases. One way of doing this, advocated by some
scientists and soon to be commercialized, is the purposeful
fertilization of the open ocean with iron. The idea is that
phytoplankton blooms will draw carbon out of the atmosphere.
Here we need to be careful. Fertilizing aquatic systems almost
always has some undesirable consequences. Hypoxia in Long
Island Sound, for example, results largely from over
fertilization by nitrogen. Sometimes enrichment causes blooms
of harmful algal species like red tide or brown tide. The pros
and cons of iron fertilization need much further investigation.
Regarding ocean acidification, my colleagues have already
discussed this issue. I just want to underscore that there will
be direct impacts of acidification on marine fishes. It is a
problem we need to look more seriously at.
Also, changes in habitat due to loss of coral and shellbed
habitats will alter the food web that supports our fisheries.
We need to understand these complex interactions.
Finally, I want to underscore the need for a comprehensive
ocean observation system. Scientists are frequently asked to
explain catastrophes like the die-off of lobsters in Long
Island Sound. We need an observation system that can track
environmental changes before, during, and after these events to
provide the clues to what happened. Otherwise we are like the
detective at the scene of a crime, with no evidence and lots of
potential suspects.
The technology exists. Let us put it to use. Such
observation systems will greatly aid resource managers in
ensuring sustainable fisheries. Thank you and I look forward to
answering your questions.
[The prepared statement of Dr. Conover follows:]
Prepared Statement of David O. Conover, Ph.D., Dean and Director,
Marine Sciences Research Center, Stony Brook University
Introduction
I thank Madame Chair Cantwell, Ranking Member Snowe, and the other
Members of the Subcommittee for the opportunity to describe to you the
likely consequences of climate change on marine fisheries. My name is
David Conover. I am the Dean and Director of the Marine Sciences
Research Center of Stony Brook University, Long Island, New York. My
research expertise involves the ecology and natural history of marine
fishes and the impacts of harvesting and other human influences on wild
fish populations. Of particular relevance to the subject of this
hearing, I have devoted much of my 30-year career to studying the
physiological mechanisms by which fish adapt evolutionarily to climate
change. Much of this work concerns species that live along the East
Coast of North America from Florida to the Canadian maritimes, a region
that encompasses dramatic changes in climate. We can learn a lot about
what to expect from climate change by studying species that span the
U.S. East Coast.
You have asked me to address the consequences of climate change for
fisheries, fish habitats, the distribution and abundance of species,
food webs, and the gaps in our knowledge that preclude our ability to
predict immediate and long term impacts. In addition, you have asked
for suggestions on how resource managers should respond to these
threats. I will begin by briefly outlining the major changes in the
ocean ecosystems that are already underway and are expected to
accelerate in the years ahead, touching briefly on ocean acidification
and then devoting most of my attention to the effects of warming. Both
the direct and indirect impacts of acidification and warming will be
highlighted. I will then discuss several East Coast examples where
already there is strong evidence that climate change is harming local
species and altering ecosystems in transitional zones. Finally, I'll
talk about short-term solutions and research needed to provide a
longer-term prognosis and options for the future.
Ocean Acidification
Knowledge of the potentially devastating impact of reduced pH on
aquatic ecosystems is not new. Decades ago it became evident that acid
rain was afflicting numerous freshwater ecosystems leading to declines
and extinctions of numerous fish and macro-invertebrate species from
certain lakes and streams that lacked a natural buffering capacity.
What is new is the recognition that acidification of entire oceans is
possible. It is caused not by acid rain, however, but from increased
CO2 in the atmosphere, which in turn leads to increased
carbonic acid in the ocean.
Most of our knowledge of the direct effects of ocean acidification
on marine organisms focuses on species known as ``marine calcifiers''
(e.g., corals, mollusks) that build skeletons or shells made of calcium
carbonate. Many of these species will suffer impaired ability to build
skeletons as pH decreases. We know less about the direct impacts of
acidification on harvested species like fishes and squids. In these
species, the response to acidification is likely to involve
physiological diseases including acidosis of tissue and body fluids
leading to impaired metabolic function. Egg and larval stages are
likely to be much more susceptible than adults, suggesting that reduced
reproductive success will be among the first symptoms to appear. The
indirect effects of acidification on fisheries will include loss of
reef habitat constructed by marine calcifiers. Many fishes depend on
the physical structure provided by coral skeletons or shell-building
organisms such as oyster reefs as essential habitat for one or more
life stages. In addition, food web alterations will likely affect
harvested species through bottom-up effects on the food chain resulting
from pH-induced shifts in the plankton community. More research is
needed to understand these complex interactions.
Ocean Warming
Temperature is a pervasive environmental factor with direct effects
on nearly all aspects of the ecology, physiology, morphology, and
behavior of poikilothermic or so-called ``cold-blooded'' animals. There
is a vast scientific literature describing the temperature-dependence
of physiological processes and thermal ecology of individuals of a
given species. Less is known about population and ecosystem level
responses to temperature change but we know enough to make fairly
strong, general predictions about the consequences of warming at least
for the species level.
All species are adapted for life over a relatively moderate range
of temperatures compared with the extremes experienced form the poles
to the tropics. Temperatures below the optimal range slow the rate of
metabolism and, if too low, can become lethal. Temperatures above the
optimal range increase metabolism and, because warmer water contains
less dissolved oxygen, a thermal threshold is reached where respiratory
demand exceeds the capacity for oxygen uptake, sometimes referred to as
the ``temperature-oxygen squeeze'' (Portner and Knust 2007). Hence,
temperature is one of the primary environmental factors that determine
the geographic range of a species. Minimum winter temperatures often
determine the high-latitude boundary (the northern boundary in the
northern hemisphere) while summer maximums determine the low-latitude
limit of a species. Even within the normal range of a species, the
dynamics of populations often show strong correlations with temperature
trends.
While scientists can use the thermal physiology of a species to
predict how it might respond to the direct effects of ocean warming,
there are indirect effects at the ecosystem level that complicate the
overall impact considerably. In temperate regions, for example, the
complex of species found at a given latitude are a mixture of those
adapted to colder or warmer thermal regimes. These species are
interconnected through a web of predatory, competitive, pathogenic,
parasitic, and mutualistic interactions that influence the abundance of
species. Invasive species also sometimes get a foothold more easily in
systems undergoing disturbance. In addition, changes in temperature may
influence the overall primary productivity of ecosystems in either
positive or negative directions (Behrenfeld et al., 2006), which may
ultimately impact fisheries yields.
In general, the impact of ocean warming should be most evident at
the northern and southern boundaries of the distribution of a given
species. These boundaries tend to be shared among numerous species, and
they tend to occur where there are sharp discontinuities in thermal
gradients. Hence, there are certain regions of the world ocean that are
transitional zones for numerous species. Cape Hatteras and Cape Cod are
two such regions. It is within these transitional regions where we are
likely to first see the strongest impacts of climate change. Most of
the phenomena described above are illustrated by changes we are now
seeing along the East Coast of the U.S., particularly within Long
Island Sound.
Impacts of Warming on Fisheries as Exemplified by Long Island Sound
The Long Island region has represented a thermal transition zone
for thousands of years. During the Pleistocene, this region was the
transition from glaciated to non-glaciated terrain. Today it still
represents a subtle but ecologically important transitional zone
between warm-water and cold-water regions.
Most temperate marine species of fishes and macro-invertebrates can
be described as having either cold-water or warm-water affinities.
Northern species like cod, winter flounder, and American lobster are
classic cold-water species. For many of these species, the Long Island
Sound region represents that southern terminus of their migration and/
or geographic distribution. Southern species like weakfish, summer
flounder, and blue crab are physiologically adapted to warm
temperatures. Long Island Sound represents the northern end of their
geographic occurrence. We are seeing strong evidence of shifts in the
relative abundance of cold-water and warm-water species in our region
that are consistent with the predictions of ocean warming.
The most well studied example is American lobster. Massive,
catastrophic summer-fall mortalities of lobsters in Long Island Sound
began in August 1999, and have continued to occur to a greater or
lesser degree in subsequent summers. An extensive federally-sponsored
research program has identified summer warming of Long Island Sound
bottom waters, coupled with hypoxia, and the outbreak of disease as the
most likely causes. One of these diseases called ``excretory
calcinosis'', discovered by scientists at Stony Brook University, is a
gill tissue blood disorder resulting directly from warm temperatures
(Dove et al., 2004). Other lobster diseases also appear to result from
the stress of high temperature and hypoxia. The result of these
multiple stresses has been a 75 percent reduction in total landings and
85 percent reduction in the overall abundance of the population. These
diseases now appear to be moving northward.
Another example of climate-induced effects on fisheries involves
the northward expansion of a disease known as ``dermo'' that afflicts
the oyster. It is caused by Perkinsus marinus, a parasite that yearly
kills 50 percent of oysters in the Gulf of Mexico. Prior to the late
1980s, the parasite was known to occur only south of lower Chesapeake
Bay. In the early 1990s, however, dermo underwent a 500 km northward
range expansion extending all the way into the Gulf of Maine.
Researchers at Rutgers University have demonstrated that the range
expansion occurred during years when winters were unusually warm (Ford
and Smolowitz 2007). The prevalence of dermo is now high from Delaware
Bay to Cape Cod, with no signs of abating.
Shifts in the relative abundance of finfish in Long Island Sound
also bear the signature of ocean warming. Like the lobster, winter
flounder is also at the southern end of its distribution and it too is
showing extremely severe declines. Commercial landings in New York are
only 15 percent of what they were 50 years ago. According to annual
resource assessment surveys conducted since 1984 by the Connecticut
Department of Environmental Protection (CTDEP), winter flounder
abundance in Long Island Sound is now less than 10 percent of what it
was in 1990. We need more research to determine if winter flounder are
declining due to warming temperatures. But when you look at the finfish
community of Long Island Sound as a whole (CTDEP 2006), evidence of
warming as the causative factor becomes much stronger. Most of the
cold-water species of Long Island Sound have been declining over the
past 15 years (e.g., lobster, winter flounder, Atlantic herring,
cunner, longhorn sculpin, sea raven, ocean pout, winter skate, little
skate) while most of the warm-water fishes have been increasing (e.g.,
striped bass, weakfish, summer flounder, menhaden, scup, striped sea
robin, butterfish, Atlantic moonfish, hickory shad).
Finally, there is also evidence from Long Island Sound that the
recent trend of warmer winters favors the growth and recruitment of
invasive species over those of native species. Researchers from the
University of Connecticut showed that exotic ascidian species (sea
squirts) benefit more from mild winters while native species benefit
more from cold winters (Stachowicz et al., 2002). Overgrowth of bottom
habitat by invasive sea squirts is becoming an increasing problem in
Long Island Sound.
Implications for Management
Resource managers need to recognize that local populations of
species near the limits of their distributional ranges will need
additional precautionary measures to protect them from extinction.
Warming and acidification represent additional stresses that make
populations less resilient to the effects of harvest. We may need to
reduce harvest of some species in certain areas to enable them to
withstand the additional stress.
Transitional regions are where the impact of climate change will
first be evident. These regions are also conduits for species exchange.
The transmittal of pathogens, predators, and invasive species across
ecosystems will increase as species migrate into new regions across
thermal and faunal boundaries such as Cape Cod, which separates the
Mid-Atlantic region from the Gulf of Maine. Management practices that
transplant species across ecosystems need to be viewed with caution.
Solutions, Their Implications, and Further Research
The ultimate and best solution is the reduction of greenhouse gases
that cause acidification and warming. One solution advocated by some
scientists and soon to be commercialized is the purposeful
fertilization of open ocean habitats that are deficient in iron. The
resulting pulses of phytoplankton growth sequester carbon from the
atmosphere and may help reduce the buildup of atmospheric
CO2. Although this possibility deserves serious scrutiny,
the ecosystem impacts of fertilization in most aquatic ecosystems
almost always contain undesirable consequences for water quality, food
webs, and fisheries. Hypoxia in Long Island Sound, for example, results
largely from over-fertilization by nitrogen, which is the limiting
nutrient in many coastal waters. Sometimes the blooms produced by
enrichment turn out to be harmful algal species like ``red tide'' or
``brown tide''. The ecological consequences of ocean fertilization on a
scale sufficient to stem the build-up of green house gases needs much
further research to evaluate the potential risks of unintended negative
impacts.
The certainty of climate change and its potential impacts on ocean
ecosystems underscore the need for a comprehensive ocean observation
system. Our ability to unravel the causes and consequences of ecosystem
change is directly dependent on the availability of a continuous time
series of many different kinds of environmental data. Gradual trends in
highly variable environmental parameters like temperature, oxygen,
salinity, pH, chlorophyll, wind, circulation patterns, and others
become evident only after many years. Fishery ecologists are frequently
asked to explain the cause of episodic events like the die-off of
lobsters in Long Island Sound, but we need an observation system that
can provide ``before, during, and after'' data to give us the clues.
Otherwise, we are like the detective at the scene of a crime with no
evidence and lots of potential suspects. The technology exists to
continuously measure numerous physical and biological parameters that
will greatly help us understand and therefore devise strategies to cope
with ecosystem alterations caused by climate change or other forces.
The number and diversity of sensors currently deployed in U.S. ocean
waters is woefully inadequate. Such observation systems will greatly
aid resource managers in ensuring sustainable fisheries.
References
Behrenfeld, M.J., R.T. O'Malley, D.A. Siegel, C.R. McClain, J.L.
Sarmiento, G.C. Feldman , J. Milligan, P.G. Falkowski, R.M. Letelier ,
and E.S. Boss, 2006: Climate-driven trends in contemporary ocean
productivity. Nature, 444(7120), 752-755.
CTDEP, Bureau of Natural Resources, Marine Fisheries Division.
2006. A Study of Marine Recreational Fisheries in Connecticut. Federal
Aid in Sport Fish Restoration, F-54-R-25, Annual Performance Report.
Dove ADM, LoBue C., Bowser P., Powell M. 2004. Excretory
calcinosis: a new fatal disease of wild American lobsters Homarus
americanus. Diseases of Aquatic Organisms 58 (2-3): 215-221.
Ford, S.E. and R. Smolowitz. 2007. Infection dynamics of an oyster
parasite in its newly expanded range. Mar. Biol. 151: 119-133.
Portner, H.O., Knust R. (2007) Climate change affects marine fishes
through the oxygen limitation of thermal tolerance. Science 315, 95-97.
Stachowicz, J.J., J.R. Terwin, R.B. Whitlatch, and R.W. Osman.
2002. Linking climate change and biological invasions: ocean warming
facilitates nonindigenous species invasions. Proc. Natl. Acad. Sci. 99:
15497-15500.
Senator Cantwell. Thank you, Dr. Conover.
Dr. Hansen?
STATEMENT OF DR. LARA J. HANSEN, CHIEF SCIENTIST, CLIMATE
CHANGE PROGRAM, WORLD WILDLIFE FUND
Dr. Hansen. Thank you very much, Madam Chair.
I'll attempt to make this show up on your screen as well.
Perhaps yes, perhaps no. Ah, there we go.
I have submitted written testimony, but for the purposes of
my 5 minutes today I would actually like to take people on a
more personal journey. In 2001, I was brought to the World
Wildlife Fund to help them design conservation strategies to
prepare for climate change. Over the course of the past 6 years
we have developed this suite of projects and I think that I
will take you through a couple of them that really illuminate
the challenges that we face in the world's oceans in response
to climate change. The basics of that have been presented by
the previous speakers very eloquently. I am going to take you
through what this means if you are a resource manager or a
conservation planner.
In the Florida Keys, which is a place near and dear to my
heart--I did my postdoctoral research there--coral bleaching,
coral disease, and hurricanes have resulted in the listing of
two coral species for the entire range of the Caribbean. It is
not clear how we can protect these species from those types of
changes since we only see more of it on the horizon.
Currently we are trying to reduce the proximal threats that
are not related to climate change in order to increase the
resilience of these systems to a changing climate, by reducing
things like pollutants. But it is not clear that we can do that
for much longer.
In the Bering Sea, we are trying to protect fisheries. The
fisheries of the Bering Sea are an enormous industry, not only
for the United States but for Russia and many other countries
of the world as well. But more importantly, this is a crucial
ecosystem to the world's oceans. It is a very productive part
of the world and we are trying to see if there are ways we can
better manage fisheries to respond to climate change.
We are also working on protecting mangroves around the
world because they protect both coral reefs and coastal systems
where humans and biodiversity live.
But all of these actions that I talk about, be it better
fisheries management, reducing pollution, or restoring
habitats, will be inconsequential if climate change is allowed
to continue at the rate it currently is. For climate change-
increasing temperatures, we recognize that there is about a
limit of 2 degrees before we cannot use these types of methods
to help these systems.
In the case of ocean acidification, we do not know what
that limit is. It is probably fairly low before we start seeing
remarkable impacts, because the oceans historically have been
believed to have a very high buffering capacity, so we would
not need to worry about things like ocean acidification. In
fact, that is not the case, as we can all--as Dr. Feely has
already indicated.
We are at a point now where we need to not only be dealing
with adaptation, but we need to be dealing with mitigation as
well. Unfortunately, we are currently dealing with neither. As
a result, I suggest a number of things. Obviously, the Congress
is doing a great job of taking on issues of mitigation, of
reducing greenhouse gas emissions. There are several bills in
process for that. But there is virtually nothing in process for
what we are doing about adaptation, and we will be seeing the
effects of climate change on every sector of society.
We need a national adaption plan or strategy. As part of
this, we also need the capacity to deal with climate change. It
is almost impossible to find people who know how to design
adaptation strategies and adaptation actions, because we have
not trained people for these types of activities. We need an
adaptation extension agency analogous to the land grant and Sea
Grant extension agencies, with also an international component
that can help people in other countries adapt.
We have been told, according to the IPCC Second, Third--
Fourth Assessment Report, second working group, that it will be
the poorest of the poor that will be affected by climate
change. In fact, I would argue that we will all be affected by
climate change, and I think that the slow recover of the Gulf
Coast following Hurricane Katrina is an excellent example of
the low adaptive capacity of even the United States, a very
wealthy country by world comparison.
We need to act now. We cannot wait and continue to do
studies. We are seeing the changes. Obviously we need to
continue to learn as we go, but we cannot wait for all the
answers before we decide what it is we are going to do. This
problem is already upon us.
Thank you very much, Madam Chair.
[The prepared statement of Dr. Hansen follows:]
Prepared Statement of Dr. Lara J. Hansen, Chief Scientist, Climate
Change Program, World Wildlife Fund
``Climate change is arguably the greatest threat to the world's
biodiversity.'' That is how I began my testimony to the Senate
Committee on Commerce, Science, and Transportation in March of 2004.
Three years later this is no less true. In fact, the situation we find
ourselves in is even more dire as was most recently highlighted in the
Intergovernmental Panel for Climate Change (IPCC) Fourth Assessment
Report released this year. Representing the top scientific experts in
their fields, the three working groups of that body present the state
of the science as demonstrating that:
1. Climate change is caused by greenhouse gas emissions from
fossil fuels, such as carbon dioxide, and land use change;
2. We are already seeing the effects of climate change around
us; and
3. We need to take action now both in terms of mitigation and
adaptation to avoid an unacceptable future.
The time to act is now.
The primary response among policymakers has been to focus on
reducing emissions of greenhouse gases, that is, mitigation of climate
change. However, as the IPCC Working Group II emphasized, and as I have
emphasized in my work over the years, adaptation--our ability to adjust
to and prepare for the changes in climate already occurring and future
changes to which our past emissions have already committed us--is now
equally important. There is no need to debate the virtues of mitigation
versus adaptation. Neither alone will solve our problems. We need both
and we need to see meaningful legislation addressing both mitigation
and adaptation during this Congressional session.
As part of a conservation organization, my colleagues and I work to
protect the world's biodiversity and natural resources. Traditional
approaches to this work have relied on creating protected areas,
limiting ``take'' of key species and resources and monitoring
ecosystems of great importance and/or at great risk. Climate change
makes these approaches inadequate. As the world's oceans warm and
acidify, storm intensity increases, sea level rises, timing and
concentrations of nutrient and contaminant run-off from terrestrial
systems change, currents and upwelling patterns stop or move, timing of
migration and lifecycle stages shifts, and ranges of species move, the
oceans can not be protected from climate change by these old
mechanisms. Conservation is now being planned across a matrix that is
changing before our eyes and we are not prepared.
It could further be argued that the United States as a whole is not
prepared. The IPCC Fourth Assessment Report asserts that climate change
will be hardest on the poorest of the poor globally. The 2005 hurricane
season indicates that the United States will not be unscathed by
climate change. It is now over a year and a half since a record number
of Category 5 storms hit our Gulf Coast, and it has still not recovered
from the battering. New Orleans is still in tatters. The calamities of
climate change will be events like these and we are not prepared.
To address climate change in our conservation planning, WWF has
adopted an approach to increase the resilience of natural systems to
climate change that we are employing in ecoregions around the planet.
This work is based on four basic tenets:
1. Protecting adequate and appropriate space. As the climate
changes species (plants and animals) will react to these
changes. They will react by altering how they live, such as
using new resources, by moving to new areas, or by disappearing
because they cannot find the habitat or resources they require.
To help ecosystems respond to climate change we need to start
planning where protected areas need to be in the future for
species survival and how they need to be managed differently to
support species groups. We need to look for locations that can
act as refuges from climate change, opportunities for networks
of reserves along climatological gradients (often across
latitude or elevation), locations with high amounts of
heterogeneity (or areas with different habitats and species)
and opportunities to support genetic diversity and gene flow.
All of these strategies try to maximize the opportunity for
species or ecosystems to respond to climate change, without
adversely affecting ecosystems with our actions.
2. Reducing all non-climate stresses. Climate change presents a
number of environmental stresses--increasing temperature,
altered precipitation patterns, sea level rise, altered
environmental chemistry to name just a few--but these stresses
are not occurring in a vacuum. There are already a host of
other environmental stresses out there, including invasive
species, over-harvest, habitat degradation and fragmentation,
disease and pests, and pollution. Unfortunately in many cases
there are synergistic interactions between these traditional
stresses and the stresses of climate change, effectively
lowering the effect or ``toxicity threshold.'' To increase
ecosystem resilience to climate change we must lower the risk
of adverse reactions by lowering the acceptable limits of these
other stresses in the environment because climate change is
already happening and our actions/inaction has already
committed us to some changes.
3. Implementing these pro-active approaches in adaptive
management so we can learn as we go. The actions we suggest are
just good sense in light of climate change. If we enact small-
scale tests and wait to implement our approaches broadly, the
system will have changed and our approaches may no longer be
useful or applicable. The window of opportunity for
preparations may close as climate change progresses.
Additionally, we do not have the funds or the human capacity to
test strategies everywhere so we need to be learning lessons to
share and implement as rapidly as possible.
4. Reduce the rate and extent of climate change. There is a
limit to our ability to adapt to climate change. For example if
we think about ocean acidification, there is a permanent
commitment to changing the pH of the ocean every time we add
more carbon to the atmosphere and it is not at all clear how we
can adapt to these changes. Best estimates are that 2+ C (3.6+
F) increase in average global temperature brings us to a point
where adaptation options become dramatically limited in
feasibility and efficacy and prohibitively expensive in terms
of cost. It is not new thinking that mitigation is necessary.
This is simply another reason why we need to act sooner rather
than later.
WWF's conservation adaptation projects are being implemented around
the world, including in our marine ecoregions. In the tropics, we are
testing how to protect coral reefs in American Samoa, Florida and the
Mesoamerican Reef of Central America. We are also restoring and
protecting mangrove forests to provide better coastal protection in
Fiji, Cameroon and Tanzania. We are planning for sea level rise in low
lying regions of the world, especially those that are home to
endangered species, like endangered sea turtles in the Caribbean and
beautiful tigers in the Sundarbans of India. In the Bering Sea of
Alaska we are working to protect the future of that region's vital
fisheries for the realities of climate change.
Some of our first work on climate adaptation was focused on coral
reefs. Coral reefs are particularly sensitive to climate change. They
bleach when ocean temperatures climb by as little as one degree
Celsius. They are unable to create the calcium carbonate skeleton that
forms the reef structure when the pH drops. And, they are damaged by
increasingly intense tropical storm activity. The fate of coral reefs
will have ramifications for human societies as well. It has been
estimated that coral reefs have a global economic value of $30 billon
in net benefits. In the case of coral reefs we are particularly
interested in increasing resilience by decreasing those non-climate
stresses that exacerbate the adverse effects of climate change; those
factors that add to the overall stress and prevent corals from being
able to withstand the stresses of climate change itself. In American
Samoa our research group worked with local stakeholders to assess the
current and potential impact of climate change on their coral reef
resources. Almost annual coral bleaching in this region may be leading
to reef degradation. Increased awareness of this issue in the region,
in part due to this project, has lead to climate change being front and
center on the agenda of the upcoming U.S. Coral Reef Task Force meeting
to be held in American Samoa.
This first project led us to explore similar issues on a reef
closer to home. In the Florida Keys, in fact for their whole Caribbean
range, there are two species of coral, Acropora cervicornis and A.
palmata, which are listed as threatened under the Endangered Species
Act. The top three factors identified as the cause of their listing are
increasing sea temperatures, hurricanes and disease. It is unclear how
a recovery plan will be developed to respond to these threats given
their inextricable link to global climate change and increasing
greenhouse gas emissions. However the larger issue in the region is not
how to protect these two species but rather how to protect the entire
reef ecosystem. We are currently developing a decision-support tool to
allow for the integration of historic coral bleaching data and water
quality data in order to assess how improving regional water quality in
the Keys may increase the resilience of those very economically
valuable coral reefs. In 2001 it was estimated that coral reefs
generated $3.9 billion in income for Broward, Mimai-Dade, Monroe and
Palm Beach counties.
Coral reefs are not the only systems at risk from climate change.
Coastal communities, both people and wildlife, also experience multiple
climate change challenges--sea level rise, increasing storm intensity,
changing precipitation, and increasing temperatures. Couple those
stresses with the high human population density and development typical
of coastal regions and climate planning becomes quite complicated. In
some regions we are working to protect coastline and in other we are
preparing for its loss.
Mangrove forests are already one of the most degraded ecosystems in
the world. They have been cut down for firewood, building supplies and
to clear coastline for development. Unfortunately these trees provide
natural protection for shoreline from sea level rise and storm surge.
Their loss has increased the vulnerability of coastal communities. WWF
is working to restore and protect mangrove forests in order to increase
coastal resilience in Fiji, Cameroon and Tanzania. As it turns out
there is an added benefit of protecting mangroves; healthy mangroves
may support healthy reefs. Mangroves filter nutrients out of the water
as it flows from land to the oceans. It turns out coral reefs prefer
low nutrient waters and when high nutrient waters flow into the oceans
it can decrease the resilience of coral reefs. Additionally mangroves
produce a compound that can filter out the harmful ultraviolet
radiation that can exacerbate coral bleaching.
Sea level rise means the loss of land. For some species appropriate
land is limited; others thrive right along the shoreline. In either of
these cases, there are almost always human communities nearby that are
also competing for this already precious space. Unfortunately it is
getting more precious every day. An interesting case study is the Key
Deer, a federally endangered species that finds suitable habitat on
just two of the Florida Keys. With an elevation of less than 2 meters
(or about six feet) at their highest point the vulnerability of the
Florida Keys to climate change is clear. If you are a Key Deer, with
nowhere to migrate in response to climate change, your future is grim.
While it is not clear what can be done for the Key Deer, WWF is trying
to help develop plans to prepare other species for climate change. In
the Caribbean basin, we are learning how sea level rise will inundate
the nesting beaches of sea turtles. Sea turtles are vulnerable
throughout their lives to climate change--their sex is determined by
the temperature of the sand in which their eggs incubate, their long
migrations and food sources are to varying degrees affected by ocean
currents potentially vulnerable to climate, some rely on coral reefs
and sea grasses which are themselves vulnerable and then their nesting
beaches are being lost as the seas rise. Often as sea level rises,
beaches retreat inland creating new coastline that would be suitable
for turtle nesting. Unfortunately human infrastructure (buildings,
roads) can prevent the generation of suitable new habitat. We are
creating a new conservation plan for sea turtles that allows us to
assess rate of sea level rise, beach elevations (looking for beaches
that can withstand more sea level rise), local geology (subsidence and
uplift), and patterns of human development. This will allow for
choosing the right places for sea turtle protected areas and developing
better coastal planning for not only sea turtles but human populations
as well.
On the other side of the planet we are dealing with a similar but
potentially more dangerous issue. In the Sundarbans of India, tigers
live on low-lying mangrove islands. It is estimated that 12 of these
islands will be lost to sea level rise by 2020. These are home to not
only the tigers but people as well. As these islands are lost, both
tigers and people will be looking for new homes, and with this may come
increasing human/wildlife interactions that can have adverse
consequences for both sides. We are again trying to develop a new
conservation plan to prepare for the habitat that both humans and
tigers will need as the landscape changes.
A similar process is occurring in our most northern oceans. In the
Arctic, record sea ice loss is causing polar bears to spend more time
on land or drown at sea. It is also making them go hungry because they
require sea ice to hunt for their primary food source, ringed seals.
More time on land means more time for potential interactions with
people. In one Russian community where we work a young woman was killed
by a polar bear near her village last year. We are now working with
these communities on ways to decrease polar bear/human interactions
without loss of life on either side through what are called ``Polar
Bear Patrols.''
In the Bering Sea climate change is causing fish species ranges to
shift (generally moving farther north) and historic fishing grounds
will no longer be as robust. This is no small concern as the Bering Sea
is home to a $2.1 billion fishing industry. WWF is working to develop
new management approaches that plan for climate change and protect the
resource as well as the livelihoods that rely upon it.
Obviously projects like these will not solve the problem of climate
change. However they encompass the level of climate awareness that
managers must now have and the range of activities they can engage in
order to increase the resilience of their systems to climate change.
They are part of a larger strategy that we must develop to address both
the cause and effects of climate change.
Virtually all of the major bills introduced in this Congress
relating to climate change are focused on mitigation, whether in the
form of across-the-board cuts in U.S. greenhouse gas emissions, or in
more targeted cuts for electric power plants, mobile sources of
emissions, etc. Given the crucial need to address the root cause of
climate change this is not misguided. However we must now also begin
the task of addressing how to respond to the effects of climate change.
At this point, bills on climate change have not addressed adaptation in
a meaningful way.
Conservation organizations are not alone in their lack of
preparedness for the effects of climate change. We need a bold new plan
in all sectors to deal with this ubiquitous challenge. WWF proposes a
legislative approach with two components. First we need a National
Strategy for Adaptation, supported not only with funding, but with an
extension agency that works to develop the myriad responses we will
need in all sectors of our society, not just the oceans, not just
natural resources and wildlife, but in civil society and the
infrastructure on which we and our economy relies--food, water,
housing, transportation, education, public health . . . the list is
endless. This extension agency could be modeled after the Land and Sea
Grant programs to work with all levels of society across the country on
specifically addressing and adapting to climate change. Second, we need
an impact assessment approach modeled after National Environmental
Policy Act (NEPA) that would require public works, infrastructure
activities and all other projects that might adversely affect natural
systems to take into account the added effects of climate change, and
address how those adverse effects could be avoided. For instance, some
pollutants become more toxic at elevated temperatures, so existing
exposure limits may not adequately protect people and ecosystems as the
planet warms and this could affect permitting for new sewage treatment
projects. In fact this approach of assessing the vulnerability of
projects to climate change should be good business practice for all
federally funded project in order to ensure their value, success and
longevity, regardless of whether they focus on natural resources.
The task of fully addressing climate change is massive, but we can
no longer ignore it.
______
Sustainable Development Law & Policy--Winter 2007
Climate Change and Federal Environmental Law
by Drs. Lara Hansen and Christopher R. Pyke*
---------------------------------------------------------------------------
\*\ Dr. Lara Hansen is Chief Scientist on Climate Change at the
World Wildlife Fund. Dr. Christopher R. Pyke is the Director of Climate
Change Services for CTG Energetics, Inc.
---------------------------------------------------------------------------
Introduction
Human activities, particularly the combustion of fossil fuels and
the large-scale transformation of land cover, affect ecosystems around
the world, Changes in temperature, precipitation, and water chemistry
are altering our environment. These changes will also affect
environmental regulatory frameworks, either rendering them ineffective
or forcing them to adapt to achieve their goals under changing
conditions.
Global temperature has increased by 0.8+ C over the last century.
Climate scientists estimate that we arc committed to an additional 0.5+
C increase due to the amount of carbon dioxide (``CO2'')
that is already present in the atmosphere.\1\ Rising temperatures have
been accompanied by a wide range of environmental changes, including,
retreat of sea ice and glaciers, sea level rise, and changes in the
intensity and frequency of storms and precipitation events.\2\ Rising
CO2 concentrations has not only changed the composition of
the air, but it is also changing the chemistry of the water:
CO2 is absorbed by the oceans, which forms carbonic acid,
causing the acidification of the oceans.\3\
These changes mean that regulations intended to protect natural
resources and promote conservation will be applied under conditions
significantly different from those that prevailed when they were
drafted. Achieving the original goals of these regulations will require
a careful assessment of long-standing assumptions, as well as decisive
action to change regulatory practices in ways that accommodate, offset,
and mitigate climate change. Three such laws will be explored in this
article: the Endangered Species Act (``ESA''), the Clean Water Act
(``CWA''), and the Clean Air Act (``CAA'').
Climate Change and the Endangered Species Act
The stated purpose of the ESA is ``to provide a means whereby the
ecosystems upon which endangered species and threatened species depend
may be conserved.'' \4\ The architects of the ESA intended to save
creatures from proximal threats, such as bulldozers and dams. Yet,
today we see clear evidence that climate change creates new threats to
already imperiled species by contributing to the disruption of
ecological processes essential to entire ecosystems. Deteriorating
conditions will impact the viability of endangered species and the
practices used to protect them through implementation of the ESA (e.g.,
listing, ``take'' permitting, and recovery planning).
For example, in 2006, two species of Caribbean coral, Elkhorn
(Acropora palmata) and Staghorn (A. cervicornis) coral, were listed as
``threatened'' for their entire range under the ESA. The listing stated
that ``the major threats to the species' persistence (i.e., disease,
elevated sea surface temperature, and hurricanes) are severe,
unpredictable, likely to increase in the foreseeable future, and, at
current levels of knowledge, unmanageable.'' \5\ This listing
identifies three key threats that all relate to climate change: rising
sea surface temperatures, disease susceptibility, and hurricane-related
impacts. Sea surface temperatures are closely related to increasing
global surface air temperatures. A severe Caribbean coral-bleaching
event in 2005 demonstrated that high temperatures cause coral bleaching
and bleaching corals become more susceptible to disease.\6\ Moreover,
as global temperatures rise, the intensity and frequency of hurricanes
may increase.\7\ The timing of this listing was particularly profound
as it followed the unprecedented 2005 Caribbean summer, during which
the region experienced the hottest water temperatures ever recorded
with large-scale bleaching followed by disease,\8\ and a record
breaking hurricane season.\9\
Recently, the U.S. Fish and Wildlife Service proposed listing Polar
Bears (Ursus maritimus). The bears rely on Arctic sea ice for access to
food and breeding sites. Their primary food source, the ringed seal
(Phoca hispida), is also an ice dependent species. The loss of nearly
30 percent of Arctic ice cover over the past century, together with the
possibility that the Arctic will be seasonally ice-free before the end
of this century, strongly suggest that climate change will jeopardize
the survival of this species.\10\
Another example is the Key Deer, which is now limited to living on
two islands in the Florida Keys. Most of the Keys have less than two
meters of elevation. If sea levels were to rise one meter, most the Key
Deer habitat would be lost. The only way to limit sea level rise and
protect remaining Key Deer habitat is to take action to mitigate the
rate and extent of climate change.\11\
These three species represent the tip of the iceberg, so to speak.
Because climatic conditions are central to basic ecological processes
that control the distribution and abundance of life, the list of
species that are or will be endangered by climate change is potentially
enormous.\12\ The most direct way to protect the ecosystems in which
these species live--the mandate of the ESA--will be to address the
cause of climate change: greenhouse gas emissions. However, because
some impacts are inevitable, it is important that we also consider how
implementation of the ESA can be used to reduce the vulnerability of
imperiled species and aid in their recovery despite changing
conditions.
Climate Change and the Clean Water Act \13\
The CWA provides the legislative foundation for the protection and
restoration of the waters of the United States. The Act seeks to
``restore and maintain the chemical, physical, and biological integrity
of the Nation's waters'' with the goal of achieving water quality that
``provides for the protection and propagation of fish, shellfish, and
wildlife, and recreation in and on the water.'' \14\ The CWA gives the
U.S. Environmental Protection Agency (``EPA'') the statutory authority
to establish water quality standards and to regulate the discharge of
pollutants into waters of the United States.
Climate and water quality are linked by hydrologic processes
involved in the global water cycle. These processes move water from the
oceans, into the atmosphere, and back down into rivers, streams,
wetlands, and estuaries. The net result is a sustainable supply of
clean, fresh water and a wide variety ecosystem services, such as
recreational opportunities and food production. It has long been
recognized that humans intervene in this cycle through activities that
intercept, store, utilize, or otherwise alter natural hydrologic
processes (e.g., the expansion of impermeable surfaces, application of
excess fertilizer, and removal of ecological filtration processes such
as wetlands). The CWA provides a framework for understanding these
sources of impairment and acts to restore impaired waters and prevent
further degradation. Over time, the CWA contributed to significant
improvements in surface water quality in the United States despite a
steadily growing population and expanding economy.
Climate change adds a new and potentially disruptive element to
these long-running efforts. The Intergovernmental Panel on Climate
Change predicts a wide variety of changes, including rising air
temperature, more frequent heat waves, more intense precipitation
events, and increasingly severe dry-spells and droughts.\15\ These
changes reflect the biophysical consequences of an overall acceleration
of the global hydrologic cycle, and these general conclusions have been
a feature of the scientific literature for nearly twenty years.
However, the local and regional consequences of these complex processes
remain difficult to predict. The key conclusion for local and regional
decisionmakers is that ``change'' will be the operative word, and
historic observations will provide an increasingly unreliable guide to
future conditions. Changes in hydrologic processes will be reflected in
changes in the quantity and quality of surface waters, and, in many
cases, they are likely to undermine important assumptions used in the
implementation of the CWA. For example:
More intense precipitation events will increase nonpoint
source pollution loads.
Increasing storm water volumes may exceed expectations and
design specifications for water treatment works and sewer
infrastructure.
Decreases in flow volume may increase in-stream pollutant
concentrations and reduce the ability of waters to accommodate
pollutant discharges.
Increases in ambient air temperature will raise temperatures
in surface waters and threaten aquatic ecosystems.
Humans may respond to some climate change-related impacts
through increased use of some pesticides, fungicides, and
fertilizers, increasing the concentrations in surface and
groundwater (e.g., expanding nuisance species).
Climate change may also decrease the toxicity thresholds of
bioindicators to these pollutants.
These changes have significant implications for the most important
and far-reaching CWA programs, including the control of point source
discharge, management of nonpoint source pollution, and environmental
monitoring.
Point source discharges are typically managed by engineered
systems. Most modern systems are designed to accommodate a relatively
wide range of environmental conditions. However, there are limits, and
climate change may drive systems unexpectedly close to their design
tolerances--sometimes risking catastrophic outcomes (e.g., levies
surrounding New Orleans). Changes to long-term, capital-intensive
investments such as sewer and stormwater facilities are costly and time
consuming. Consequently, those involved in their design, construction,
and operation need to begin anticipating the impacts of climate change
immediately.
Nonpoint source pollution represents a different kind of problem.
By definition, nonpoint loads come from many small sources. Pollution
is controlled by means of so-called Best Management Practices
(``BMPs''), such as riparian buffers, retention ponds, and cover
cropping. Climate change will alter both the volume and concentration
of nonpoint source pollution and the effectiveness of BMPs. Managing
nonpoint source pollution under changing climatic conditions will
require thoughtful monitoring and attention to the relative
sensitivities of different land uses and BMPs. In many cases,
thoughtful land use planning and the selection of climatically-robust
BMPs may be able to achieve many nonpoint source pollution control
goals despite changing conditions.
CWA programs are based on observations of the actual water quality
conditions and activities that may contribute to impairment.
Observations include information about a water body's physical,
chemical, and biological condition. These indicators are used to assess
compliance with water quality standards and attribute degradation to
specific sources. This process typically assumes that drivers of change
can be found within a given watershed. However, climate change will
alter water quality regardless of local actions and, in most cases,
climate-related changes will compound or exacerbate on-going water
quality problems and a myriad of existing conditions and on-going
restoration activities. In other words, climate change will make an
already complicated analysis significantly more challenging.
Untangling complex, changing mixtures of factors contributing to
water quality will require monitoring systems that allow for separation
of climatic and non-climatic factors. The EPA uses a system of
bioindicators to evaluate the biological integrity of surface
waters.\16\ These are typically fish, aquatic insects, and other
organisms that have well-known responses to changes in water quality.
These bioindicators provide synthetic measures of water quality that
can help diagnose specific causes of impairment or degradation.
However, bioindicators are themselves part of ecological systems that
will respond to changes in both climate and water quality.\17\ The
myriad examples offered in toxicological literature demonstrate that
elevated temperature and altered water chemistry can exacerbate the
toxicity of pollutants. Consequently, the use of this important
information for attribution will require understanding the response of
specific bioindicators to changing conditions and specifically
selecting indicators with methods that allow for partitioning between
climatic and non-climatic impacts.\18\
Climate Change and the Clean Air Act
The stated purpose of Title IV of the CAA is ``to reduce the
adverse effects of acid deposition.'' \19\ It seeks to address
Congressional findings that:
1. the presence of acidic compounds and their precursors in the
atmosphere and in deposition from the atmosphere represents a
threat to natural resources, ecosystems, materials, visibility,
and public health;
2. the principal sources of the acidic compounds and their
precursors in the atmosphere are emissions of sulfur and
nitrogen oxides from the combustion of fossil fuels;
3. the problem of acid deposition is of national and
international significance;
4. strategies and technologies for the control of precursors to
acid deposition exist now that are economically feasible, and
improved methods are expected to become increasingly available
over the next decade; and
5. current and future generations of Americans will be
adversely affected by delaying measures to remedy the
problem.\20\
The CAA is primarily targeted at reduction of sulfur
(``SOX'') and nitrogen oxides (``NOX''). It also
may be interpreted or amended to apply to greenhouse gases. Rising
atmospheric CO2-levels acidify ocean water and threaten
marine resources and ecosystems. Reducing CO2 emissions
would help mitigate this global problem, potentially using CAA
mechanisms originally designed for SOX and NOX.
For example, Title IV of the CAA encourages ``energy conservation, use
of renewable and clean alternative technologies, and pollution
prevention as a long-range strategy, consistent with the provisions of
this title, for reducing air pollution and other adverse impacts of
energy production and use.'' \21\ These activities also reduce
CO2, emissions and in so doing mitigate the effect of
atmospheric CO2, on the ocean.
Finally, CO2, acidification, like SOX and
NOX, is a problem of national and international scope.
Current and future generations will be affected by any delay in taking
action. Due to the fact that roughly half of anthropogenic emissions
end up in the oceans and because CO2 remains in the
atmosphere for a substantial period of time, CO2 will
continue to acidify the Earth's oceans for decades or centuries to
come. Failure to limit anthropogenic emissions will only perpetuate
this problem. The likelihood that reducing greenhouse gas emissions
will limit acidification is very high.
To date, the EPA has been unwilling to regulate CO2 as
an air pollutant, and legal action by states and municipalities on this
issue awaits a decision by the U.S. Supreme Court. Interpreting or
amending the CAA to regulate CO2, as an acidifying agent may
be an effective mechanism for curbing CO2 emissions.
Conclusion
The ESA, the CWA, and the CAA form the foundation of the effort to
protect and restore the environment in the United States. Climate
change undermines the ambitious goals of these laws. Changes in climate
can jeopardize the survival and recovery of endangered species. Climate
change is likely to alter hydrologic processes in ways that could
undermine the goal of providing clean, safe water resources. Climate
change can also exacerbate long-standing air quality issues by
increasing the likelihood of unhealthy or ecologically-damaging
conditions. The first step is to take our collective foot off our
fossil fuel-powered accelerator by implementing prompt and deliberate
measures to reduce the emission of greenhouse gases.
This first step, while necessary, is not sufficient. We are already
committed to significant levels of climate change due to the
accumulation of CO2, in our oceans and atmosphere. Achieving
conservation and resource protection goals will require developing
robust and resilient practices that explicitly anticipate and address
the potential for changing conditions. In the years ahead, efforts to
mitigate and adapt to climate change will constitute important, new
dimensions to these critical pieces of environmental legislation.
Endnotes
\1\ G.A. Meehl et al., How Much More Global Warming and Sea Level
Rise?, 307 Science 5716 (2005).
\2\ Kerry Emanuel, Increasing Destructiveness of Tropical Cyclones
Over the Past 30 Years, 436 Nature 7051 (2005).
\3\ Intergovernmental Panel on Climate Change, Summary for
Policymakers, Climate Change 2001: Impacts, Adaptation, and
Vulnerability (Feb. 2001), available at http://www.ipcc.ch/pub/
wg2SPMfinal.pdf (last visited Feb. 13, 2007) [hereinafter IPCC].
\4\ 16 U.S.C. 1531 (2000).
\5\ Rules and Regulations. Endangered and Threatened Species: Final
Listing Determination for Elkhorn Coral and Staghorn Coral, 71 Fed.
Reg. 26,852 (May 9, 2006).
\6\ See Mark Eakin, Management During Mass Coral Bleaching Events:
Wider Caribbean Case Study, International Tropical Marine Ecosystem
Management Symposium (October 16-20, 2006); see also National Park
Service, Coral Bleaching and Disease Deliver ``One-Two Punch'' to Coral
Reefs in the U.S. Virgin Islands (October 2006), available at http://
www.nature.nps.gov/water/Marine/CRTF_Fact_
Sheet1-1a.pdf (last visited Jan. 21, 2007) [hereinafter NPS].
\7\ Kevin E.Trenberth and Dennis J. Shea, Atlantic Hurricanes &
Natural Variability in 2005, 33 Geophysical Research Letters, June 27,
2006, at 1; see generally Emanuel, supra note 2.
\8\ NPS, supra note 6.
\9\ Trenberth & Shea, supra note 7.
\10\ Endangered and Threatened Wildlife and Plants; 12-Month
Petition Finding and Proposed Rule to List the Polar Bear (Ursus
maritimus) as Threatened Throughout its Range, 72 Fed. Reg. 1064 (Jan.
7, 2007).
\11\ See generally U.S. Fish and Wildlife Service, Southeast Region
Workforce Management Plan, available at http://www.fws.gov/southeast/
workforce/images/WorkforcePlan.pdf (last visited Feb. 13, 2007).
\12\ J.R. Malcolm et al., Global Warming and Extinctions of Endemic
Species From Biodiversity Hotspots, 20 Conservation Biology 538, at
538-548 (2006).
\13\ See generally C.R. Pyke, & R.S. Pulwarty, Elements of
Effective Decision Support for Water Resource Management Under a
Changing Climate, 8 Water Resources Impact 5 (Sept. 2006).
\14\ 33 U.S.C. 1251 (2001).
\15\ IPCC, supra note 3.
\16\ U.S. EPA website, Biological Indicators of Watershed Health.
http://www.epa.gov/bioindicators/html/indicator.html (last visited Feb.
13, 2007).
\17\ See generally Stephen R. Carpenter et al., Global Change and
Freshwater Ecosystems, 23 Ann. R. Of Ecology And Systematics 119
(1992).
\18\ B.G. Bierwagen and S. Julius, A Framework for Using
Biocriteria as Indicators of Climate Change, Second Annual Meeting of
the International Society for Environmental Bioindicators, April 24-26,
2006.
\19\ 42 U.S.C. 7651 (2003).
\20\ 42 U.S.C. 7651 (2003).
\21\ 42 U.S.C. 7651 (2003).
Senator Cantwell. Thank you, Dr. Hansen.
Dr. Kruse?
STATEMENT OF GORDON H. KRUSE, Ph.D., PRESIDENT'S
PROFESSOR OF FISHERIES AND OCEANOGRAPHY, SCHOOL OF FISHERIES
AND OCEAN SCIENCES, UNIVERSITY OF
ALASKA FAIRBANKS
Dr. Kruse. Madam Chair and members of the Committee: It is
my honor to testify to you this morning. My name is Gordon
Kruse. I am the President's Professor of Fisheries at the
School of Fisheries and Ocean Sciences, University of Alaska,
Fairbanks.
My objectives are to discuss potential mechanisms and
effects of climate change on living marine resources in Alaska,
future outlook for these resources, and implications for
management and research needs. As just one measure of the value
of marine ecosystems, in 2005 landings from Alaska totaled 5.7
billion pounds, representing 59 percent of the total 9.6
billion pounds landed in the United States.
Because the Arctic has been warming much faster than the
rest of the globe and this accelerated trend is projected to
persist, studies on its effects in Alaska are critically time
sensitive. A large body of scientific evidence implicates
climate as being primarily responsible for many observed
changes in marine ecosystems off Alaska. Three of the important
interrelated scales of variability I will discuss today are
inter-annual, decadal, and global warming.
Regarding inter-annual or year to year variability, an
important component is the El Nino, which occurs every 2 to 7
years. In association with warm ocean temperatures, species
more typical of tropical waters, such as ocean sunfish and
Pacific white-sided dolphins, extend their distributions into
Alaska. El Ninos appear to have become more intense in the
latter half of the 20th century, possibly as a manifestation of
global warming.
Coincident with the very strong 1997-1998 El Nino, the
first ever massive bloom of coccolithophores, which are very
small, rather non-nutritious microscopic plants or
phytoplankton, was observed in the eastern Bering Sea. The
bloom was so massive that it was observed from space. Some
seabird species experienced massive die-offs and others
produced very few surviving offspring owing to feeding
problems.
Much decadal-scale variability occurs in the form of
climate regime shifts every 10 to 30 years. For instance, in
the northeast Pacific Ocean temperatures were warm in the mid-
1920s to the mid-1940s, cool in the mid-1940s to the late
1970s, and warm since then. Marine ecosystem changes since the
regime shift of the 1970s include declines in forage fishes,
crabs and shrimps, and increases in salmon and groundfish,
presumably as a result of changes in nutrients supporting
phytoplankton production.
Global warming will have differential thermal effects on
the species distributions. In the Bering Sea, adult red king
crab and snow crab have shifted to the north since the late
1960s, likely due to an aversion to increasing bottom
temperature. It appears that the planktonic larvae of both
species are now being carried by ocean currents too far north,
beyond preferred nursery habitats. At the same time, warmer
temperatures have allowed predators of young crabs, such as
Pacific cod and rocksole, to shift their distributions to the
north. For these reasons, Bering Sea crabs may fare poorly
under continued global warming.
One species that seems to have particularly benefited
greatly from conditions since the late 1970s is arrowtooth
flounder, a species at its highest record levels of abundance.
This species is a voracious predator that consumes large
amounts of pollock, cod, and other commercially valuable
species. Unfortunately, the flesh of the arrowtooth flounder
has low market value owing to enzymes that degrade flesh
quality.
The Bering Sea is being restructured by ongoing warming
temperatures and loss of sea ice. In years of extensive sea
ice, an ice edge phytoplankton bloom occurs in April, which
falls to the sea floor and supports bottom or benthic species
like crabs and clams. In years of little sea ice, the spring
bloom occurs in May or June and it stays in the upper layers,
where it benefits water column or pelagic species, like
pollock. A sharp decline in sea ice has favored pelagic over
benthic species in the southeast Bering Sea since the late
1970s.
Recent studies are indicating that similar changes are now
beginning to occur in the northern Bering Sea. In these
northern areas, loss of benthic production will adversely
affect walruses and spectacled eiders, which feed primarily on
benthic clams or other bivalves.
What about implications of global warming on fishery
management? The North Pacific Fishery Management Council is
considering management actions with respect to likely northward
expansion of fish resources into the northern Bering Sea and
Arctic Ocean. At its June 2007 meeting, the North Pacific
Fishery Management Council is considering action that may ban
bottom fishing in the northern Bering Sea except for the
conduct of experiments to study fishing effects.
Over the long-term, the Council may develop an Arctic
Fishery Management plan, but these efforts are severely
constrained by lack of information on marine fish and
invertebrate resources in the region.
In general, global warming will cause greater uncertainty
about the productivity of fish stocks. Under science-based
management, increasing uncertainty translates into more
precaution, which will likely mean reduced fish harvests in
Alaska.
I have recommended five research needs to improve our
ability to forecast and address likely future marine ecosystem
changes in Alaska with regard to global warming. First, it is
critical at this time to establish baseline assessments of
marine ecosystems of the northern Bering Sea and Arctic Ocean.
Second, establishment of Integrated Ocean Observing Systems
is essential to monitoring and understanding the effects of
global climate change on these marine ecosystems. Third, it is
important to invest in studies on the biology, life history,
and ecology of very poorly studied species in the northern
regions. Fourth, it is important to establish linkages between
climate models and marine ecosystem and fishery models, so that
the effects of global warming can be better quantified. And
finally, climate change coupled to the likely increases in
marine transportation, development of other human uses of
marine ecosystems off Alaska, heighten the need for further
development of an ecosystem approach to management.
Thank you, Madam Chair, for the opportunity to speak to you
today and I would be pleased to answer any questions.
[The prepared statement of Dr. Kruse follows:]
Prepared Statement Gordon H. Kruse, Ph.D., President's Professor of
Fisheries and Oceanography, School of Fisheries and Ocean Sciences,
University of Alaska Fairbanks
Introduction
Madam Chair and members of the Committee, it is my honor to testify
to you this morning. My name is Gordon Kruse. Since 2001, I have been
the President's Professor of Fisheries and Oceanography at the School
of Fisheries and Ocean Sciences, University of Alaska Fairbanks. Prior
to my current position, I directed the marine fisheries research
program for the Alaska Department of Fish and Game for 16 years, where
I was the lead Science Advisor to the State of Alaska on state and
Federal marine fishery management. I have been a member of the
Scientific and Statistical Committee (SSC) of the North Pacific Fishery
Management Council (NPFMC's) for 7 years, including the two most recent
years as chair (2005-2006) and the two prior years as vice-chair (2003-
2004). I served an additional 11 years as a member of the NPFMC's Crab
Plan Team and Scallop Plan Team and co-authored the original crab and
scallop Fishery Management Plans. I am the current chair of the Fishery
Science Committee for the North Pacific Marine Science Organization
(PICES), an international marine science organization involving China,
Japan, South Korea, Russia, Canada and the U.S.
Objectives of Testimony
My objectives are to discuss: (1) potential mechanisms and effects
of climate change on living marine resources in Alaska, (2) future
outlook for these resources and implications for management under
continued global warming, and (3) uncertainties associated with gaps in
our understanding that require further research.
Importance of Marine Ecosystems Off the Coast of Alaska
Alaska is unique in that it is bounded by three large marine
ecosystems: the North Pacific Ocean, Bering Sea, and Arctic Ocean
(including the Beaufort and Chukchi Seas). These are some of the
world's most productive ecosystems, supporting thousands of marine
mammals, millions of seabirds, and trillions of fish and shellfish
belonging to hundreds of species.
These Arctic and subarctic oceans provide priceless ecosystem
services, including human use. Since before recorded history, Native
Alaskans have depended on the bounty of these ecosystems for their very
existence. Still today, many of these communities remain as
subsistence-based (barter) economies, and their harvests of fish,
shellfish, mammals and other resources (e.g., bird eggs, kelp) provide
the majority of their diets.
These ecosystems support extremely valuable commercial fisheries
that provide both U.S. food security and foreign exports that
contribute toward the national balance of trade. More than half of the
total U.S. fishery landings come from the waters off Alaska. In 2005,
landings from Alaska totaled 5.7 billion pounds, representing 59
percent of the total 9.6 billion pounds landed in the U.S. (NMFS 2007).
While important fisheries occur in the Gulf of Alaska and Aleutian
Islands, most of this catch is taken from the eastern Bering Sea, owing
to its broad, highly productive continental shelf. In 2005, the
Nation's top seafood port was again Dutch Harbor-Unalaska, accounting
for 888 million pounds of landings worth $283 million exvessel (before
value-added processing). Moreover, seven of the Nation's top 20 seafood
ports are located in Alaska. The Bering Sea supports the world's
largest fishery (walleye pollock), largest flatfish fishery (yellowfin
sole), and largest salmon (sockeye) fishery. Other valuable commercial
fisheries target a diversity of species of crabs, rockfishes, flatfish
(flounders and soles), cod, halibut, herring, and other fish and
invertebrates. These same waters provide world-class recreational
fishing opportunities for non-resident visitors and Alaskan residents
alike for salmon, halibut, rockfish and other species.
Resource Sustainability Versus Variability
In their report to the nation, the Pew Oceans Commission (2003)
noted that Alaska's fisheries were ``arguably the best managed
fisheries in the country. With rare exception, the managers have a
record of not exceeding acceptable catch limits set by scientists. In
addition, the North Pacific Fishery Management Council and Alaska Board
of Fisheries have done more to control bycatch and protect habitat from
fishing gear than any other region of the Nation.'' The sustainability
of groundfish, salmon and other fishery resources in Alaska is tied
directly to conservative, science-based fishery management.
Nonetheless, there are clear historical cases of overharvest and
resultant collapse of living marine resources, even in Alaska--examples
include the Steller's sea cow (hunted to extinction in 1768), northern
fur seal (1700s-early 1800s and again in the late 1800s-early 2000s),
great whales (mid 1800s-mid 2000s), sea otters (mid 1700s-early 2000s),
yellowfin sole (1960s), and Pacific ocean perch (1960s-1970s). Causes
of recent declines in Steller sea lions, northern fur seals, shrimp,
and king, Tanner and snow crabs are much less clear. Although human
effects have been implicated in many of these recent examples and
undoubtedly humans have contributed to varying degrees, a large body of
scientific evidence has emerged in support of climate change as being
primarily responsible for major shifts in the marine ecosystems off
Alaska. Environmental variability affecting marine ecosystems occurs
over a wide range of time scales; the scales most relevant to most
marine animal populations are seasonal to decadal and longer. Owing to
our rather short history (few decades) of research and monitoring of
marine organisms in Alaska, much of our outlook for impacts of global
warming on marine ecosystems is based upon our understanding of the
mechanisms and effects operating on shorter time scales, as summarized
below.
Effects of Seasonal Climate Variability on Living Marine Resources in
Alaska
Seasonal climate variability is vital to the productivity of
temperate, subarctic and Arctic marine ecosystems. In these regions,
there is a seasonal ``battle'' between winds that mix deep, nutrient-
rich waters into the photic zone and solar heating that warms the upper
layers of the ocean, causing thermal stratification that retains
microscopic plants (phytoplankton) in the upper layers of the ocean
where they can grow under sufficient light penetration and nutrient
concentrations.
In the spring, when solar heating wins the battle, an intense bloom
of large phytoplankton occurs, providing large amounts of food to
microscopic animals (zooplankton) that, in turn, bloom in abundance.
This sequential burst in abundance of phyto- and zooplankton serves as
food to higher trophic levels, including the planktonic early life
stages (larvae) of many commercially important species of fish and
shellfish, as well as adults of some species of planktivorous marine
mammals (e.g., humpback whales) and seabirds (e.g., crested auklet). In
other words, this spring bloom fuels the engine that supports much of
the productivity of marine ecosystems in Alaska. The timing of herring
spawning, hatching of red king crab larvae, and outmigration of salmon
smolts are tied to this remarkable annual event. As summer progresses,
nutrients in the warm upper layers of the ocean become depleted,
overall production tends to decline, and other species of small
phytoplankton adapted to low-nutrient conditions become prevalent.
In the fall, as winds strengthen and solar heating diminishes, the
water column mixes, stability breaks down and a smaller fall bloom may
occur. However, phytoplankton are mixed to deeper waters where light
levels are too low to sustain net growth and the engine that fuels the
marine ecosystem slows down. In winter, productivity is low, but, even
at this time of year some species (e.g., some flatfish) have adapted
strategies for optimum survival as winter spawners. In the following
spring, the cycle is repeated again.
Each species has evolved unique life history strategies to be
successful in these seasonally dynamic marine ecosystems. For many
species of marine fish and invertebrates, their success depends upon
the synchrony in time and space of their early life stages (eggs and
larvae) with abundances of suitable food, the abundance (or lack
thereof) of predators, and ocean currents that carry them (advection)
to nursery areas most amenable to their survival. Likewise, the success
of seabird and marine mammal populations depends largely upon the
ability of adults to secure adequate prey while feeding their young on
rookeries.
Effects of Interannual and Decadal Climate Variability on Living Marine
Resources in Alaska
El Nino
Although an understanding of seasonal variability in environmental
variables is important toward understanding the strategies by which
species thrive within marine ecosystems, it is the year-to-year
(interannual) variability in climate and ocean processes that
determines how animal populations change over time. One important
component of interannual variability that occurs every 2-7 years is El
Nino/La Nina, an oscillation of a coupled ocean-atmosphere system in
the tropical Pacific having important consequences for weather in the
North Pacific and around the globe. Prominent features of an El Nino
include the relaxation of the trade winds and a warming of sea surface
temperature in the equatorial eastern Pacific, extending along the U.S.
west coast into Alaskan waters. Species more typical of subtropical and
tropical waters extend their distributions into Alaska during El Nino
events. For instance, during the 1997-1998 El Nino, albacore tuna were
caught off Kodiak Island and ocean sunfish were observed in the
northern Gulf of Alaska (Kruse 1998). Global surface mean temperature
anomalies provided by NOAA's National Climate Data Center suggest that
El Ninos became more intense and more frequent in the latter half of
the 20th century, quite possibly as a manifestation of global warming.
Thus, range extensions and first-time sightings of southern species
have become more common in recent years.
Beyond the curiosity of such unusual sightings, more far-reaching
marine ecosystem changes can be associated with El Nino events.
Coincident with the 1997-1998 El Nino, salmon run failures occurred in
western Alaskan river systems imposing severe economic and social
hardships in some western Alaskan communities (Kruse 1998). A Federal
disaster was declared by the U.S. President. Also, in 1997, the first-
ever massive bloom of coccolithophores (a non-nutritious microscopic
phytoplankton covered with calcium carbonate platelets) was observed in
the eastern Bering Sea. The bloom was so dense and expansive, that it
was easily observed by satellites orbiting the Earth. A massive die-off
of short-tailed shearwaters was associated with reduced availability of
their preferred prey (euphausiids). Murres, a dive-feeding seabird,
produced fewer offspring, likely because dense coccolithophore
concentrations obscured their vision and ability to feed. It is
important to recognize that these ecosystem effects were likely the
product of an unusual combination of El Nino, decadal climate
variability, global warming, and other atypical regional conditions.
However, this suite of climatic conditions set the stage for repeated
coccolithophore blooms in the eastern Bering Sea for half a dozen years
after this initial event.
Decadal Climate Regime Shifts
Much marine ecosystem research in Alaska since the 1980s has
documented decadal climate variability patterns that have led to regime
shifts every 10-30 years. The Pacific Decadal Oscillation (PDO) is one
index of such shifts, based on warm-cold patterns of sea surface
temperature in the northern North Pacific Ocean. Some have likened the
warm phase of the PDO to an extended El Nino situation. For instance,
ocean temperatures in the northeast Pacific were typically warm in the
mid-1920s to mid-1940s, cool during the mid 1940s-late 1970s, and warm
since then. The opposite pattern was experienced in the northwestern
Pacific.
The regime shift of the late 1970s has been particularly well
studied. Since the late 1970s, Alaskan waters have experienced more
frequent winter storms associated with an intensified Aleutian Low
Pressure System, increased freshwater discharge into the Gulf of
Alaska, a stronger Alaska Coastal Current (which flows in a counter-
clockwise fashion around the gulf), and warmer ocean temperatures.
These changes appeared to have altered the flux of nutrients, leading
to a marked increase in the biomass of zooplankton in the Gulf of
Alaska. Other major ecosystem changes associated with this regime shift
include a decline in forage fishes, crabs, and shrimps and increases in
the abundances of salmon and groundfish (Anderson and Piatt 1999). Some
research supports the hypothesis that declines in a number of
populations of marine mammals and seabirds are related to observed
shifts in marine food webs (e.g., decline in forage fish) in Alaska.
However, as with any complex ecosystem with limited monitoring, the
evidence is less than conclusive.
Decadal-scale variability in the extent of sea ice formation has
had profound effects on the Bering Sea marine ecosystem. Sea ice forms
and melts seasonally spreading from the northern to southern Bering Sea
shelf waters. Timing of the spring bloom depends heavily on ice
formation and melt. In years of extensive ice coverage, the ice thaws
more slowly and melt water stratifies the upper water column with
buoyant, low salinity water. If this stratification occurs sufficiently
late (e.g., April), then sunlight is adequate at that time of year to
cause an early spring bloom near the ice edge. However, there is a
dearth of zooplankton in this cold melt water, so much of the
phytoplankton sinks ungrazed to the seafloor where it benefits bottom-
dwelling (benthic) species, such as clams, crabs and other
invertebrates. On the other hand, in years when ice is thin and less
extensive, it melts in February or March; the lesser amount of
freshwater is inadequate to stratify the water column and sunlight is
too weak at that time of year to support a plankton bloom. In such
years, the spring bloom is delayed until May or June after the sun has
had sufficient time to heat a stratified layer of warmer water. Warmer
ocean temperatures at this time of year support growth of the
zooplankton community and much of the phytoplankton production is
grazed by water column (pelagic) species, such as walleye pollock.
Sea ice in the southeast Bering Sea has declined markedly from
covering 6-7 months in the late 1970s to spanning just 3-4 months each
winter since the 1990s. As the ice-edge bloom may account for a large
fraction of the total annual primary production in the eastern Bering
Sea, there is considerable concern that declines in productivity have
occurred with reductions in sea ice since the late 1970s. Although
long-term records of phytoplankton are lacking, declines in summer
zooplankton have been clearly documented in the eastern Bering Sea by
the Japanese research vessel OSHORO MARU since at least 1990.
Effects of Global Warming on Living Marine Resources in Alaska
Terrestrial Impacts of Global Warming in Alaska
Increases in global air and sea temperatures have been clearly
documented since the 1800s. On land, observed changes in Alaska are
dramatic and well known, including retreat of nearly all glaciers,
melting of permafrost and associated structural damage to buildings and
roads, and increased insect outbreaks (e.g., spruce bark beetle) in
coniferous forests and an associated increase in frequency of forest
fires. Along the coast of western Alaska, higher sea levels and lack of
shore-fast sea ice in winter has led to extensive coastal erosion
during storms, prompting the imminent costly relocation of dozens of
Native villages.
Climate and Oceanographic Changes With Global Warming
A composite land-ocean index of global temperature provided by NASA
shows that temperature changes since the 1880s reflect the combined
influences of the two major frequencies already discussed--El Ninos
(every 2-7 years) and decadal variability (10-30 years)--plus a long-
term increase in temperature associated with global warming (*100
years). Because our history of research and monitoring of marine
organisms is very short (decades) relative to the century-long time
scale associated with global warming, the outlook for living marine
resources under continued global warming is based largely upon our
rather limited understanding of recent variability and mechanisms
associated with those observed changes. The outlook for these marine
resources also depends upon the accuracy of future projected changes in
temperature, precipitation and winds from climate forecast models.
Based on the working group of the Intergovernmental Panel on
Climate Change in 2007, the near-term projection is for an average
global increase of 0.2+ C per decade over the next two decades. The
Arctic has been warming twice as fast as the rest of the globe since
the mid 1800s, and this accelerated trend is projected to persist for
the higher latitudes into the foreseeable future. Based on these IPCC
models, increased precipitation is also very likely in the higher
latitudes. High-latitude changes in wind patterns are also projected,
but specific details in the projections concerning storm frequency and
intensity are somewhat less certain.
Shifts in Species Distribution and Abundance
Each species has its own preferred optimum temperatures within a
wider range of temperatures suitable for its growth and survival. With
warming ocean temperatures, species at the southern end of their
distributions (e.g., snow crabs in the southeastern Bering Sea) are
expected to contract, whereas those at the northern ends of their
distributions (e.g., Pacific hake in southeastern Alaska) are expected
to expand northward.
Increased temperatures may benefit some species and disfavor
others. With the warming experienced in the last two decades, in-river
temperatures in British Columbia have exceeded 15+ C, which causes
stress in sockeye salmon, increasing susceptibility to disease and
impairing reproduction. Studies have shown that mortality is positively
related to temperature and river flow in Fraser River sockeye salmon.
Turning back to the poor salmon runs in western Alaska in 1997-1998
mentioned earlier, among other potential causes, anecdotal reports
found a high incidence of a parasite, called Ichthyophonus. Infected
fish did not dry properly when smoked (a common means of preservation
by subsistence users) and had white spots on internal organs and
muscle. Follow-up studies found that 25-30 percent of adult chinook
salmon returning to the Yukon River in 1999-2002 were infected (Kocan
et al., 2003). Many of the diseased fish appear to have died before
spawning. The spread and pathogenicity of this parasite is correlated
with Yukon River water temperature in June, which increased from 11+ C
to 15+ C over 1975 to 2002 at Emmonak (river mile 24). Such examples of
adverse impacts of increasing temperatures on salmon may become more
common in Alaska with continued global warming.
Warming temperatures are expected to increase the northward
migration of piscivorous predators into the future. Pacific mackerel
and jack mackerel, species common to the coast of California, have
extended their distributions into British Columbia in recent warm
years. The productivity of Pacific mackerel populations is favored
during warm years off California. Mackerel compete with and prey on
juvenile salmon; reduced survival of sockeye salmon on the west coast
of Vancouver Island is correlated with the abundance and early arrival
of Pacific mackerel in British Columbia. The impact of mackerel
predation and competition with salmon is a concern for Alaska. Mackerel
have already been encountered in Southeast Alaska by salmon troll
fishermen.
There are additional concerns about the northward extension of
other predators, such as spiny dogfish in Alaska. A colleague from the
University of Washington and I have an ongoing project to evaluate the
evidence for an increase in dogfish abundance, as well as to evaluate
the life history and productivity of dogfish and management
implications in Alaska. Bycatch of dogfish is an increasing problem to
fishermen, particularly in the salmon gillnet and halibut/sablefish
longline fisheries in Alaska. On the one hand, dogfish bycatch causes
gear damage (gillnet) and hook competition for more valuable species
(sablefish and halibut), but, on the other hand, this species could
provide new economic opportunities (dogfish supply the fish and chips
industry in Europe). Determination of sustainable harvest levels is
problematic for this abundant species that has a low rate of annual
productivity associated with delayed maturity and low reproductive
rate.
In the Bering Sea, the centers of distribution of adult female red
king crab and snow crab have shifted to the north since the late 1960s
and early 1970s, likely due to increases in bottom temperature (Loher
and Armstrong 2005, Orensanz et al., 2004, Zheng and Kruse 2006). The
larval stages of both species are planktonic--subject to passive drift.
Given the northward flow of prevailing ocean currents and the probable
fixed location of juvenile nursery areas, the northward shift of
females has most likely adversely affected the ability of these
populations to supply young crabs to the southern end of their
distribution in recent decades. At the same time, warming ocean
temperatures have allowed predators of young crabs, such as Pacific
cod, rock sole, and skates, to shift their distributions to the north.
So, the young stages of crab not only have to deal with settlement into
suboptimal habitats, but they have to navigate the gauntlet of
increased predation by groundfish. These two mechanisms may be leading
reasons why crabs have generally faired poorly since the late 1970s
regime shift. For these same two reasons, crabs may continue to fair
poorly under continued global warming. On the other hand, groundfishes
like pollock and cod may continue to benefit.
One species that seems to have benefited greatly from conditions
since the late 1970s is the arrowtooth flounder, a species at its
highest recorded levels of abundance and still increasing. This species
is a voracious predator that consumes large amounts of pollock, cod,
and other commercially valuable groundfish and shellfish.
Unfortunately, the flesh of the arrowtooth flounder has low market
value owing to enzymes that degrade the flesh quality. So, future warm
ocean conditions may continue to result in a shift from commercially
valuable species, like pollock and cod, to this species, which has low
market value.
Other predatory species that may increase in Alaska with continued
global warming include seasonal predators, such as albacore tuna. This
species would provide new economic opportunities in Alaska, perhaps to
the detriment of salmon fisheries.
Restructuring of Ecosystems
Earlier, I discussed the role of sea ice extent on funneling energy
to the benthic ecosystem (early spring bloom) or the pelagic ecosystem
(late spring bloom). Although the trend since the late 1970s has been
toward a late spring bloom favoring pelagic species (such as pollock)
in the southeastern Bering Sea, the spring bloom remains largely an
ice-edge bloom in the northern Bering Sea, where the ecosystem remains
benthic dominated (e.g., clams). This benthic production is essential
for a number of charismatic species, such as walruses and spectacled
eiders that feed on benthic clams and other bivalves. All, or nearly
all, of the world's populations of spectacled eiders overwinter in a
small area between St. Lawrence Island and St. Matthew Island in the
eastern Bering Sea. In the past decade with an increase in air and
ocean temperatures and a reduction in sea ice, there has been a
reduction in benthic prey populations and a displacement of marine
mammals (Grebmeier et al., 2006). With a commensurate increase in
pelagic fishes, the northern Bering Sea is shifting from a benthic to a
pelagic ecosystem, posing risks to benthic prey-dependent species of
seabirds and marine mammals. This benthic to pelagic trend is expected
to increase and expand northward with continued global warming.
Loss of sea ice in the Bering Sea is likely to have major impacts
on ice-dependent marine mammal species, such as ring seals and bearded
seals. Ring seals excavate caves (lairs) under the ice in which they
raise their young for protection from the weather and predators. Ring
and bearded seals feed on a variety of invertebrates and fishes. Both
seals are major components of the diet of polar bears. Polar bears also
have the capacity to kill larger prey, such as walruses, a species with
seasonal migrations also tied to the advance and retreat of sea ice.
Therefore, it seems very likely that the loss of sea ice associated
with global warming will have serious impacts on these ice-dependent
marine mammals.
Potential for Invasive Species
An additional area of concern under global warming is invasive
species. With increasing ocean temperatures, cold thermal barriers to
warm-water invasive species may become removed. One key species of
concern is the European green crab, a species that is native to the
North and Baltic Seas. Unintentionally introduced as an invasive
species, the green crab has consumed up to 50 percent of manila clams
in California, and it was blamed for the collapse of the soft-shell
clam industry in Maine. This species has the potential to alter an
ecosystem by competing with native fish and seabirds. Its recent
arrival on the U.S. west coast and potential to expand northward with
global warming causes concerns for Alaska with respect to our Dungeness
crab fishery and aquaculture farms for oysters and clams.
Changes in Seasonal Production Cycle
Increased temperatures may result in earlier stratification,
perhaps advancing the timing of the spring bloom. In such case, the
continued success of some species depends upon their ability to spawn
earlier so that their early life history stages continue to match the
spring bloom. Additionally, greater heat in the ocean may lead to
prolonged summer-like conditions favorable to small phytoplankton that
thrive in low nutrient conditions, including some phytoplankton species
that produce toxins, such as paralytic shellfish poisoning. Food chains
based on small phytoplankton (typical of summer) tend to be less
productive than those based on large phytoplankton (typical of the
spring bloom), because they require more steps of energy conversions
along the food chain to support upper trophic level species, such as
seabirds, marine mammals, and commercially important fish including cod
and halibut. So far, this seasonal cycle outlook is based solely upon
increased temperatures; other important considerations are the
forecasted future changes in storm frequency and intensity. If greater
storminess in the Gulf of Alaska and Bering Sea is associated with
global warming, then the increased mixing could somewhat compensate for
the tendency for increased stratification caused by warmer
temperatures, perhaps resulting in little change in the timing of the
spring bloom. However, in such case, given the temperature control of
the rate of many physiological processes (including reproduction) of
cold-blooded marine fish and invertebrates, a challenge for many
species will be to maintain current spawning timing despite warming
temperature conditions.
Ocean Acidification
As greenhouse emissions continue to increase, the ocean soaks up
more and more CO2, which when dissolved in water, becomes
carbonic acid. Such increases lower the pH of seawater, causing a
critical concern for species with calcium carbonate skeletons.
Preliminary results of studies in Alaska indicate that declining
seawater saturation of calcium carbonate induced by ocean acidification
may make it more difficult for larval blue king crabs to harden their
shells (J. Short, NMFS, Auke Bay Laboratory, pers. comm.). Juvenile
king crabs had substantially increased mortality, slower growth, and
slightly less calcified shells when exposed to undersaturated seawater
conditions projected for their rearing habitat within the coming
century in the North Pacific Ocean. These preliminary results indicate
that continued increasing carbonation of the ocean surface layer as a
result of increasing atmospheric CO2 may directly affect
recruitment of commercially important shellfish. Other witnesses on
this panel have outstanding expertise on ocean acidification and will
speak in much greater detail on this topic.
Management and Economic Implications
One need not look further than the Bering Sea pollock fishery in
2006 for an example of the sort of management implications expected
under global warming. During the B (fall) fishing season, pollock were
farther north and west than normal. Diesel fuel prices were high. The
at-sea (factory trawler fleet) sector has the ability to conduct 7-10
day fishing trips and a byproduct of their fish harvests is fish oil,
which they burn in their boilers and generators. On the other hand,
smaller shore-based vessels only have capacity for 2-4 day trips and
they cannot produce fish oil. The northward shift of pollock, typical
of expectations under global warming, had relatively small impact on
the at-sea sector, but had significant adverse impacts on the shore-
based fleet, owing to reduced access to the resource and increased
operational costs. Under northward shifts in fish resources, the shore-
based fleet will need to shift to a mothership-type fishery or will
need to relocate plants in new northern ports at greater investment of
capital.
Over the near term, the NPFMC is currently considering management
actions with respect to the potential northward expansion of pelagic
and other fishery resources into the northern Bering Sea and Arctic
Ocean. One major problem is that current surveys do not extend into the
northern Bering Sea, much less the Arctic, so allowance of fisheries to
follow the fish north would be conducted under increased uncertainty,
perhaps at greater risk to previously unexploited benthic resources,
which in turn could place sensitive populations of marine mammals
(e.g., walrus) and seabirds (e.g., spectacled eider) as risk. At its
June 2007 meeting, the NPFMC is scheduled to take action on a proposal
to define and mitigate essential fish habitat in the eastern Bering Sea
including an SSC proposal to allow fishing in the northern Bering Sea
only under an experimentally designed study to test fishing impacts
upon which future decisions can be based. Over the longer term, the
NPFMC is considering management options for the Arctic Ocean, perhaps
under a new Arctic Fishery Management Plan. Management options for the
Arctic are constrained by a serious lack of information on the marine
fish and invertebrate resources in this region. The reliance of species
of marine mammals and seabirds, as well as Native communities, on the
living marine resources of these northern areas, heightens the gravity
of management decisions for the Arctic Ocean.
Long-term forecasts of the implications of global warming and
fisheries management in Alaska are highly speculative, given present
levels of understanding. Just as there was a reorganization of marine
ecosystems after the regime shift of the late 1970s, marine ecosystems
off Alaska might be expected to reorganize again, perhaps to a new
unobserved state, in response to a climate regime shift associated with
continued global warming. If so, then a commensurate reorganization of
the fishing industry is to be expected. Uncertainty increases as
conditions (e.g., temperature, percent sea ice cover) move outside the
range of historical observations. Under science-based management,
increasing uncertainty typically translates into more precaution. Thus,
more precautionary management under greater uncertainty, coupled to the
increasing use of ecosystem-based fisheries management, will likely
result in more conservative fish harvests in Alaska in the future.
Data Gaps and Research Needs
Predictions of future changes of marine ecosystems for the Gulf of
Alaska, Aleutian Islands, and eastern Bering Sea are uncertain, partly
owing to gaps in our understanding of mechanisms affecting the dynamics
of living marine resources and partly due to uncertainties in climate
forecast models at the level of detail necessary for the Alaska region.
A combination of improved monitoring, process-oriented studies,
modeling, and policy development are recommended to improve our ability
to forecast and address likely future marine ecosystem changes in
Alaska:
Arctic baselines--very few data are available on the
abundance, distribution, and life history of marine species in
the northern Bering Sea and Arctic. It is critical at this time
to establish baseline understanding of community structure and
function before the Arctic region is perturbed by human impacts
and climate change.
Integrated Ocean Observing Systems--establishment of routine
observing systems for physical and biological features of
marine ecosystems off Alaska is essential to monitoring the
effects of global climate change.
Studies of physiology and life history. Models only go so
far; the biology and life history of many species off Alaska
are poorly known, including functional relationships between
their growth and survival and environmental conditions. In
order to understand the effects of global warming and human
effects on these populations and associated ecosystem
consequences, it is essential to invest in studies of basic
biology, life history, and physiology of poorly studied
northern marine species. Physiological studies can reveal a
great deal about the impacts of increasing temperature on the
scope for growth and survival of northern species.
Coupled climate-ecosystem and climate-fisheries forecasting
models. It is imperative to establish explicit linkages between
climate forecast models and regional ecosystem and fishery
models so that outlooks for changes in marine ecosystems and
fisheries can be made more quantitative and less qualitative.
In June 2007, PICES will convene a workshop on linking climate
and fisheries forecasts, but this is just a very initial step
in a process that will require substantial efforts.
Ecosystem approach to management. Climate change is just one
of a suite of both human and naturally occurring factors that
need to be considered in the management of living marine
resources. Effective management of marine resources off Alaska
will become increasingly complex, given the uses of these
resources by coastal Native communities and higher trophic
level species (e.g., birds and mammals). Potential for
increased marine transportation and oil and gas exploration and
development further heighten the need for an ecosystem approach
to management.
Thank you, Madam Chair, for the opportunity to speak to you and
your committee today. I would be pleased to answer any questions you or
other committee members may have.
References
Anderson, P.J., and J.F. Piatt. 1999. Community reorganization in
the Gulf of Alaska following ocean climate regime shift. Marine Ecology
Progress Series 189: 117-123.
Grebmeier, J.M., J.E. Overland, S.E. Moore, E.V. Farley, E.C.
Carmack, L.W. Cooper, K.E. Frey, J.H. Helle, F.A. McLaughlin, and S.L.
McNutt. 2006. A major ecosystem shift in the northern Bering Sea.
Science 311: 1461-1464.
Kocan, R., P. Hershberger, and J. Winton. 2003. Effects of
Ichthyophonus on survival and reproductive success of Yukon River
chinook salmon. U.S. Fish and Wildlife Service, Office of Subsistence
Management, Final Report 01-200.
Kruse, G.H. 1998. Salmon run failures in 1997-1998: A link to
anomalous ocean conditions? Alaska Fishery Research Bulletin 5(1): 55-
63.
Loher, T., and D.A. Armstrong. 2005. Historical changes in the
abundance and distribution of ovigerous red king crabs (Paralithodes
camtschaticus) in Bristol Bay (Alaska), and potential relationship with
bottom temperature. Fisheries Oceanography 14: 292-306.
NMFS (National Marine Fisheries Service). 2007. Fisheries of the
United States, 2005. National Marine Fisheries Service, Current Fishery
Statistics 2005, Silver Spring, MD.
Orensanz, J., B. Ernst, D.A. Armstrong, P. Stabeno, and P.
Livingston. 2004. Contraction of the geographic range of distribution
of snow crab (Chionoecetes opilio) in the eastern Bering Sea: an
environmental ratchet? CalCOFI Report 45: 65-79.
Pew Oceans Commission. 2003. America's living oceans: charting a
course for sea change. A report to the nation: recommendations for a
new ocean policy. Arlington, VA.
Zheng, J., and G.H. Kruse. 2006. Recruitment variation of eastern
Bering Sea crabs: climate forcing or top-down effects? Progress in
Oceanography 68: 184-204.
Senator Cantwell. Thank you, Dr. Kruse.
Admiral Watkins, welcome. Let me thank you again for your
leadership on the U.S. Commission on Ocean Policy, something
this Committee has had a lot of involvement with, starting with
Senator Hollings' bill on the Oceans Policy Act, and my
colleagues Senator Stevens and Senator Inouye and many others
have had much involvement in this. We are glad you are back
before the Committee.
STATEMENT OF JAMES D. WATKINS, ADMIRAL (RET.),
U.S. NAVY; CHAIRMAN, U.S. COMMISSION ON OCEAN POLICY;
CO-CHAIR, JOINT OCEAN COMMISSION INITIATIVE
Admiral Watkins. Thank you very much, Madam Chair and
distinguished members of the Subcommittee, for inviting me to
participate in today's hearing. I submitted a much longer
statement for the record that I hope will be included therein.
I appear before you today representing the interests of the
U.S. Commission on Ocean Policy, as well as the Joint Ocean
Commission Initiative, which I co-chair with Leon Panetta. As
you know, he was Chair of the Pew Ocean Commission, a
privately-funded commission. Because we were not doing very
much in Washington toward establishing a National Ocean
Commission Pew decided to go ahead anyway, which I think scared
the Congress and they passed the Ocean Policy Act of 2000,
which led to our commission.
I want to thank you, particularly the Senate, for the work
that you have done to bring national visibility to the oceans.
While today's hearing is focused primarily on the issue of
increasing acidification of the oceans and the impact on living
marine resources, I appreciate the opportunity to come and
speak to the broader issue of the role oceans play in climate
change and the need to pursue strategies, how to mitigate and
adapt to these changes.
As public awareness of climate change and its potential
economic and environmental consequences has increased, so has
the level of urgency to take action. Unfortunately, few people
fully appreciate the fundamental role oceans play in governing
climate through their immense capacity to store and distribute
heat and their part in the carbon cycle. I have never seen one
article on climate change that ever mentions the oceans and I
think it is a tragedy. They are the first victims and they are
also the hope for mankind to come out of this and to adapt to
it.
We have global ocean circulation and heat flux models that
clearly indicate major changes are under way. Yet we still lack
a clear understanding of the underlying dynamics of these
processes and are even less knowledgeable about activities
occurring along the highly dynamic coastal margins, where
ecological and economic activities are of greatest importance
to humans and many of the impacts of climate change, such as
sea level rise and coastal storms, will be directly felt.
Clearly, a more coherent strategy is needed, and a core
element of such a strategy must include increased attention to
the role of the oceans and impacts on ocean resources. Let me
proceed by focusing my remarks on three key points that I hope
my written statement communicates.
Congressional leadership. First, our oceans, coasts, and
Great Lakes need a voice and strong leadership and we are
counting on the members of this Committee to help fill this
role. The ocean community is in the process of a major
organizational transition, moving away from an outdated, highly
structured, institutional approach toward an integrated process
that more closely resembles the function of natural systems. We
call that ecosystem-based management.
This transition is necessary in order to respond to the
host of problems impacting the ecological health and economic
viability of the oceans. These problems range from impacts
associated with climate change, such as acidification, sea
level rise, more intense coastal storms, to degradation issues
such as water pollution, habitat loss, overfishing, and
invasive species.
The problems facing the oceans are too large and too varied
to continue the current piecemeal approach to management and
science. It will take leadership and vision from Members of
Congress to lay the foundation for a transition to ecosystem-
based management. It will be difficult and require some painful
decisions, but it is incumbent upon you to recognize the need
for reform and to move the process forward, and today's hearing
hopefully is a major step toward this objective.
Governance reform. My second point builds squarely on the
concerns raised in my first point. Governance problems in the
oceans community are severely limiting the oceans community's
capacity to provide the scientific information and management
options needed by Congress to make critical policy decisions.
Given the oceans' fundamental role in climate change, this
weakness in the ocean community is impacting its capacity to
make meaningful contributions toward the effort to understand
and address climate change.
We need a new governance regime within the Federal
Government that moves away from the stove-piped, command and
control organization where the budget process often discourages
inter-agency cooperation. The Joint Initiative has made ocean
governance reform one of its highest priorities and the urgency
of this issue has only escalated, given the need to address
ocean-related science and management demands associated with
climate change.
We must focus on improving our capacity to more accurately
assess the processes influencing climate change and place
greater attention on designing and implementing a comprehensive
strategy that balances resources across the spectrum of
scientific disciplines, that is physical, chemical, and
biological, and sectors, that is research, monitoring, and
modeling, as well as expand support for translating this data
into information that will allow you, Congress, to establish
policies aimed at meeting the goal of improving the resiliency
of the coastal communities and ecosystem.
My final point is straightforward: The time to act is now.
Leon and I are committed to pursuing the implementation of the
two Commissions' recommendations through establishment of the
Joint Initiative because we feel strongly that a failure to
respond to problems facing our oceans and coasts now will
result in irreversible damage to our economy and environment.
The urgency of the need for action is further highlighted by
growing concern over impacts associated with climate change and
the ocean's role in the process.
A much more comprehensive and robust science enterprise,
one that includes a better understanding of the ocean's role in
climate change, is required to more accurately predict the rate
and implications of change at the global through local level,
as well as to enable a more thorough evaluation of options for
mitigating and accommodating this change.
One of the first steps in the process of strengthening the
science enterprise should be a commitment to building a
comprehensive environmental monitoring system. Clearly, an
integrated ocean observing system such as the one recommended
in Senate 950, which is cosponsored by many members of this
Subcommittee, should be a key element of such a system.
Yet progress toward this goal is limited and appears to be
moving backward. A recent NRC study out of the National
Academies found that remote sensing satellite programs of NASA
are at serious risk due to a $500 million decrease in funding
for its Earth Science program and that the next generation of
satellites on the drawing board are generally less capable than
the current, rapidly diminishing system.
This situation must be addressed and a comprehensive
monitoring system that includes support for data management and
analysis and modeling must be the core of a national strategy.
I will conclude by noting that the recent elevation of
concerns surrounding climate change and its economic and
environmental implications validate similar concerns voiced by
the oceans community in the release of the U.S. Commission on
Ocean Policy and Pew Ocean Commission reports. At the heart of
the matter is the need for a more robust science enterprise
capable of advancing our understanding of the processes that
drive our planet and guide the decisions of policymakers. The
integration across agencies and scientific disciplines can only
occur if we succeed in implementing a new governance regime
that facilitates greater collaboration, including resources and
expertise outside of the Federal system.
So I am appealing to you publicly, as Leon and I have done
in private, to take up the mantle of governance reform in the
ocean community. It is the critical first step in a process
toward realigning and focusing the resources and energy of the
ocean community toward restoring the health and viability of
our oceans and coasts. I can assure you that the rewards will
be immense and enduring and will provide you with a lasting
legacy.
Thank you for the opportunity to appear and I stand ready
to answer your questions.
[The prepared statement of Admiral Watkins follows:]
Prepared Statement of James D. Watkins, Admiral (Ret.), U.S. Navy;
Chairman, U.S. Commission on Ocean Policy; Co-Chair, Joint Ocean
Commission Initiative
Madame Chair, Senator Snowe and members of the Subcommittee: Thank
you for the invitation to testify at today's hearing. I appear before
you today representing the interests of the U.S. Commission on Ocean
Policy as well as the Joint Ocean Commission Initiative, which I co-
chair with Leon Panetta. The Joint Initiative is a collaborative effort
of members of the U.S. Commission on Ocean Policy and the Pew Oceans
Commission. The purpose of the Joint Initiative is to advance the pace
of change for meaningful ocean policy reform.
Leon and I believe that this is an important hearing and hopefully
is the first of many hearings that will examine the fundamental role
oceans play in global climate change, as well as the impact climate
change is having on our oceans and coasts. We trust that the Members of
the Committee will work closely with the multitude of other
congressional committees that share jurisdiction over climate change
related issues and will champion the need for greater attention to
governance needs and the commitment of resources to support ocean-
related science, management, and education.
Multi-jurisdictional problems, such as climate change, are becoming
more common. In the work of our commissions, we found almost the
identical problem in the effort to deal with the many problems facing
our oceans, coasts, and Great Lakes. The lack of governance regimes
capable of reaching across the diversity of congressional committees
and Federal agencies is severely hampering our capacity to deal with
these issues. Thus, while I understand that today's hearing is focused
on the issue of the increasing acidification of the oceans and the
impact on living marine resources, I appreciate the opportunity to
speak to the broader issue of the role of oceans in climate change and
the importance of pursing strategies now to help coastal communities
adapt to the inevitable changes that will occur in the coming years.
Oceans Role in Climate Change
As public awareness of climate change and its potential economic
and environmental consequences has increased, so has the level of
urgency to take action to mitigate the causes of this change and to
make preparations to adapt to its impacts. Unfortunately, few people
fully appreciate the fundamental role oceans play in regulating climate
through their capacity to store and distribute heat and their role in
the carbon cycle. As a nation, we are even less knowledgeable about the
ramification of this change on the health of coastal and pelagic
ecosystems and their capacity to provide the services upon which we've
come to rely. This lapse has resulted in limited understanding of the
complexity of ocean-related physical, geochemical, and biological/
ecological processes that are influencing and being influenced by the
ongoing change. The consequences of this lack of knowledge are
significant. Policymakers struggle to evaluate alternatives to address
climate change because the levels of uncertainty associated with the
short- and long-term impacts of proposed options are relatively high
and the science underpinning these decisions is inadequate. Clearly, a
more coherent strategy is needed to address climate change, and a core
element of such a strategy must include increased attention to the role
of the oceans.
Oceans are key drivers in the Earth's heat and carbon budgets,
storing one thousand times the heat of the atmosphere and absorbing a
third of all anthropocentric carbon dioxide generated over the last few
centuries. Furthermore, oceans not only store heat, but transport it
around the globe, as well as vertically through the water column in
ocean basins, making it a driving force of climate change. While our
knowledge of physical oceanographic processes is further advanced than
that of geochemical and biological processes, it is still rudimentary
due to the lack of a comprehensive monitoring regime. As a result, we
have ocean circulation and heat flux models that clearly indicate major
changes are in progress. However, we still lack a clear understanding
of these processes on a global scale, and are even less knowledgeable
about activities occurring along the highly dynamic coastal margins,
where ecological and economic health are of the greatest importance to
humans and many of the impacts of climate change--such as sea level
rise and coastal storms--will be directly felt.
Further complicating the situation is the lack of understanding of
the interrelationship among the physical, geochemical, and biological
processes. As today's hearing clearly demonstrates, we need to know the
implications of ocean acidification on marine ecosystems--such as
phytoplankton communities, coral reefs, and fish larva. We also need to
know the rate of ice sheet melt and its impact on coastal communities,
polar ecosystems, and regional weather patterns.
The complex relationship between oceans and climate change, as we
currently understand it, cries out for reform in two core areas,
governance and science. Congress must respond to the chorus of
criticism directed at the lack of a coherent strategy and framework for
addressing the challenges facing our oceans and coasts. This strategy,
in turn, must be integrated into a broader national initiative to deal
with climate change. It is incumbent upon Congress to take this
opportunity to look beyond parochial interests and issue-specific
legislation, and work toward a governance regime and management
policies that place greater emphasis on cooperation and collaboration
within the Federal Government, while capitalizing on the wealth of
scientific expertise and resources that reside outside the Federal
system.
Governance
The complexity and breadth of issues associated with efforts to
understand, mitigate, and adapt to climate change make it essential
that the Nation have a coherent and comprehensive strategy to guide
this work. This is a daunting challenge given the multitude of
governmental and nongovernmental entities that have a vested interest
in this issue and its long-term impact on the health and viability of
the nation's economy and environment. The ocean community has been
struggling with this same problem, albeit on a slightly smaller scale.
But the challenge remains the same, we need a new Federal governance
regime that moves away from the stove-piped, command and control
organization in which individual departments and agencies formulate
policies and budgets that are reviewed by the Office of Management and
Budget and then sent to Congress for a similar review by the
appropriate committee of jurisdiction. While there is a continuing
effort to integrate programs and activities, it is the exception not
the rule. In addition, the budget process often discourages interagency
cooperation as funding for multi-agency programs is subject to cuts or
reductions during internal agencies budget negotiations, compromising
the integrity of the broader strategy and promoting further competition
among Federal and non-governmental players.
But don't take my word for it. There are a number of credible
entities that have recognized that governance problems are impeding the
Nation's capacity to respond to some of its most pressing challenges
and have recommended solutions. Earlier this spring the National
Research Council (NRC) responded to a request from the White House
Climate Change Science Program to identify lessons learned from past
global change assessments. In its report, the NRC cited the lack of a
long-term strategic framework for meeting the climate change research
mandate as an outstanding weakness of the current system.\1\
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\1\ Analysis of Global change Assessments: Lesson Learned. National
Research Council 2007.
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Testimony by former administration officials who oversaw the
climate change research program reiterated these concerns last Thursday
in a hearing before a House Energy and Commerce Subcommittee, where
recommendations were made to establish a program office with a sense of
permanence, the political power to make decisions across agencies, and
the authority over budgets.\2\ These recommendations closely track
those made by the two ocean commissions, which advocated for a new
management regime, based in the Executive Office of the President that
would have the authority to coordinate efforts and guide the
distribution of resources throughout the Federal Government in an
integrated system that reached across jurisdictional boundaries of
individual agencies.
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\2\ Hearing before the House Science and Technology Committee,
Subcommittee on Energy and the Environment; Reorienting the U.S. Global
Change Research Program Toward a User-Driven Research Endeavor. http://
science.house.gov/publications/hearings_markups_details.aspx?
NewsID=1798 May 3, 2007.
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Such a vision was partially implemented in the ocean community when
the President established the Committee on Ocean Policy (COP). However,
the COP's charge is limited to coordination. It lacks institutional
independence and a leader charged with resolving interagency disputes
and representing the interest of individual agency ocean programs in
the budget process. Consequently, efforts to move a new national ocean
policy forward have languished and the ocean community's capacity to
contribute toward the scientific and management needs to address
climate change have been compromised.
Similar problems exists in Congress, where cross-cutting issues
such as oceans and climate fall under the jurisdiction of multiple
committees and subcommittees. Take the case of ocean acidification. The
Commerce Committee clearly has jurisdiction; however, the Environment
and Public Works Committee has authority over water pollution and water
quality issues, the Energy and Natural Resources Committee has a role
regarding emissions from energy facilities, which are a major source of
CO2, and the Committee on Appropriations funds authorized
activities. The same diversity of oversight authority exists in the
House, significantly complicating efforts to develop a comprehensive
strategy to address climate change. In the 108th Congress, the U.S.
Commission on Ocean Policy identified a total of 58 standing committees
and subcommittees having jurisdiction over ocean-related issues in the
House and Senate.\3\ An early assessment of the 110th Congress shows
little change or consolidation.
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\3\ U.S. Commission on Ocean Policy, Appendix F. 2004.
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Further evidence of support for a more coherent approach to
science-related policy issues is reflected in the growing interest in
reestablishing an Office of Technology Assessment (OTA). OTA was a
congressional office charged with providing nonpartisan research on
technical and scientific issues pending before Congress, but was closed
in 1995. As Congress struggles with increasingly sophisticated and
complex technical issues such as biomedical research and climate
change, an entity such as OTA can provide timely and issue specific
guidance that would complement the more exhaustive, costly and time
consuming review process performed by the National Academies. Congress
relies on credible and readily available information to make informed
policy decisions. Right now, the lack of information on oceans and
coasts, or a clear strategy for collecting and translating this
information into products and services useful to decisionmakers and
managers, is hobbling Congress' ability to perform its role.
Thus, the focus must turn to improving our capacity to more
accurately assess the processes and phenomena influencing climate
change and society's impact on such processes and phenomena. This will
require much greater attention and support being devoted to the broader
problem of designing and implementing a strategy that balances
resources among basic and applied research, monitoring and analysis,
and modeling. This strategy must also be expanded to incorporate
support for translating and utilizing this information to evaluate the
effectiveness of mitigation, adaptation, and other management actions
aimed at meeting the goals of increasing the resiliency of coastal
communities and ecosystems.
Given the complexity and interdisciplinary nature of the issues
surrounding climate change, progress toward these goals will require
changes in the operation and coordination of Federal agencies and the
Federal budget process. The National Oceanic and Atmospheric
Administration (NOAA) is the logical lead Federal agency to oversee the
climate change science program; however, public and private confidence
in the agency is lacking. This is due, in great part, to the outdated
organizational structure of the agency and the lack of resources that
have been provided to fulfill its expanding mandate. The opportunity is
ripe to reevaluate and realign NOAA's programs along its core
functions, which include: assessment, prediction and operations;
scientific research and education; and marine resource and area
management. This step, taken in combination with an effort to enhance
the oversight role of the President's Committee on Ocean Policy, would
lay the foundation for a major transition in the ocean and atmospheric
policy that would be of enormous long-term benefit to Congress and the
public.
Congress should also take advantage of this opportunity to address
science agency mission and funding inconsistencies that are hampering
the collection and synthesis of long-term data measurements. While NASA
and NSF are charged with developing new approaches to collecting,
analyzing, and integrating data, NOAA has the charge--but lacks the
technical expertise and fiscal resources--to maintain increasingly
important remote and in situ observation platforms capable of sustained
data collection (the compilation of long-term data sets). These long-
term data sets are crucial to understanding the rate of change over an
extended period. Further exacerbating the situation is a disjointed
data management system that is preventing scientists from fully
utilizing data that are currently being collected. Given the
consolidation of science agencies (NOAA, NASA, and NSF) responsible for
ocean and atmospheric research under the jurisdiction of the Commerce
Committee and its sister appropriations subcommittee, the opportunity
exists to more closely link their complementary programs through both
the authorization and appropriations processes. While this proposal may
disturb many of those in the community who have a vested interest in
programs associated with the individual agencies, in the long-term
their collaboration is essential if our Nation is to succeed in making
progress toward understanding and responding to climate change while
also restoring the health of our oceans and coasts.
Clearly, a careful reevaluation of the governance regime guiding
climate and ocean-related science and management programs is needed to
overcome the obstacles that are currently hampering efforts to develop
a comprehensive response to climate change. Whatever action Congress
takes, it should look beyond the current models and existing
organizational structure to ensure that both ocean and climate change
programs are broad-based and charged with developing a balanced
strategy that incorporates science, management and outreach. Anything
less will perpetuate an approach that has proven to be ineffective and
is now jeopardizing the health and welfare of current and future
generations.
Science
Credible scientific information is essential as the Nation begins
the process of developing a new regime to mitigate and adapt to climate
change. Better science, when linked with improved risk management and
adaptive management strategies will help guide a process that must deal
with the relatively high levels of uncertainty surrounding mitigation
alternatives and the range of impacts associated with climate change. A
much more comprehensive and robust science enterprise--one that
incorporates a better understanding of the oceans' role in climate
change--is required to more accurately predict the rate and
implications of change at the global-through-local level, as well as to
enable more thorough evaluation of options for mitigating and
accommodating this change.
While the United States is making a significant financial
commitment to understanding climate change, the inadequacy of the
current strategy has become clear and reform is urgently needed.
Research that has been primarily focused on physical science and
validation of climate change must expand to incorporate greater
attention to the role and contributions of biogeochemical and
ecological processes, as well as interactions among these three
processes. This will require a significant commitment of new resources
and will increase the complexity of the science strategy to understand
and respond to climate change. However, these actions cannot be avoided
if the science community is going to be responsive to Congress' need
for credible scientific information to guide its decisionmaking
process.
One of the first steps should be a commitment to building a
comprehensive environmental monitoring system. We are supposedly well
on our way to fulfilling our international commitment to support
climate observing systems--which according to the most recent report
from the Climate Change Science Program is over 50 percent complete.
However, support for this system is in trouble, which is compounded by
the fact that considerably fewer resources are dedicated to supporting
an ocean-focused component of the observing system. A recent NRC study
found that remote sensing satellite programs in NASA are at great risk
and that the next generation of satellites is generally less capable
than the current, rapidly diminishing system. Projected budgets show
U.S. investment in these capabilities falling by 2012 to its lowest
level in two decades.\4\ Support for a dedicated ocean observing
program appeared in the President's budget for the first time this
year, at the level of $16 million, a fraction of what Congress has been
providing in recent years.
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\4\ Earth Science and Applications for Space: National imperatives
for the Next Decade and Beyond, NRC 2007.
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As a consequence our knowledge of physical ocean-related processes
is limited, and our capacity to understand biogeochemical and
ecological processes languishes due to the lack of capacity to study,
much less monitor and model these systems and their responses to
change. The expert scientific witnesses appearing before the
Subcommittee today have testified to this fact, presenting us with
quantifiable data that humans have contributed to the increased
acidification of the oceans and that there are very real and
potentially damaging consequences associated with this change. Yet, the
ocean scientific community does not have access to funding to support
large-scale field experiments, study environments that are naturally
more acidic, or more fully examine the geologic record to understand
past events that may have resulted in similar conditions.
It is now obvious that enhanced and integrated observing systems
are a key element underlying a robust ocean and climate science
strategy. From a research perspective this need was clearly articulated
in the release of the Administration's Ocean Research Priorities Plan
and Implementation Strategy in January, in which the deployment of a
robust ocean-observing system was highlighted as a critical element of
the plan. Such an observing system will require a commitment to deploy
and maintain infrastructure and instrumentation, such as satellites,
research vessels, buoys, cabled underwater observatories, and data
management networks. A sustained, national Integrated Ocean Observing
System (IOOS), backed by a comprehensive research and development
program, will provide invaluable economic, societal, and environmental
benefits, including improved warnings of coastal and health hazards,
more efficient use of living and nonliving resources, safer marine
operations, and a better understanding of climate change. However, the
value of this system will be fully realized only if an adequate
financial commitment is also provided to support integrated,
multidisciplinary scientific analysis and modeling using the data
collected, including socioeconomic impacts. Unfortunately, support for
the lab and land-based analysis of the data derived from these systems
is often inadequate, diminishing the value of these programs, while
support for socioeconomic analysis is virtually nonexistent.
The lack of a comprehensive climate change response strategy and
supporting governance regime that integrates fundamental research and
development, monitoring and analysis, and modeling efforts is a major
weakness in our national effort. It must be immediately addressed to
ensure that policymakers have the scientific information necessary to
guide their deliberation regarding both mitigation and adaptation
strategies. Congress should develop legislation, perhaps with guidance
from the National Research Council, requiring the development of a
comprehensive science strategy that incorporates support for ocean-
related sciences with a focus on enhancing the predictive capacity of
physical and ecological models. This advancement is necessary to
provide policymakers and the public with the information necessary to
make informed decisions regarding the collateral impact of potential
mitigation strategies--such as carbon sequestration in or under the
oceans or biofuel production that results in increased runoff of
agricultural pollutants into coastal watersheds--and strategies for
increasing the resiliency of coastal communities and marine ecosystems
to climate generated impacts.
Conclusion
The recent elevation of national conversation surrounding climate
change and its economic and environmental implications validate similar
discussions voiced by the ocean community upon the release of the U.S.
Commission and Pew Commission reports. At the heart of the matter is
the need for more a robust science enterprise capable of advancing our
understanding of the processes that drive our planet and can better
guide the decisions of policymakers. The integration across agencies
and scientific disciplines, with a focus of developing products and
services useful to policymakers and the public, will only occur if we
succeed in implementing and integrating new governance regimes for
climate change and ocean policy that facilitates greater collaboration,
including resources and expertise outside of the Federal system.
This transition must be well thought out and deliberate, perhaps
pursuing a phased approach such as that recommended in the U.S.
Commission report. In it, we recommended that the initial focus be on
strengthening NOAA, followed by a realignment and consolidation of
ocean programs that are widely distributed throughout the Federal
Government. The final phase would be the consolidation of natural
resource oriented programs under a single agency. This approach
responds to the recommendation of the Volker Commission, which
identified the proliferation and distribution of agencies and programs
throughout the Federal Government as a major hindrance to efficiency
and effectiveness of the Federal system.\5\
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\5\ National Commission on the Public Service: Urgent Business for
America: Revitalizing the Federal Government for the 21st Century
http://www.brookings.edu/gs/cps/volcker/volcker_hp.htm 2004.
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I am appealing to you publicly, as Leon and I have done in private
to many of you, to take up the mantle of governance reform in the ocean
community. It is the critical first step in the process toward
realigning and focusing the resources and energy of the ocean community
toward restoring the health and viability of our oceans and coasts. I
understand it will be difficult, but increased public awareness and
concern about the health of the environment has provided us with a
unique and timely opportunity to leave a lasting legacy, one we can
appreciate when sitting on a beach--free of closure and swimming
advisory signs--on a sunny summer afternoon with our children or
grandchildren while looking out over the horizon of a sparkling blue
sea.
Madame Chair and Members of the Subcommittee, I appreciate the
opportunity to appear before you today, and look forward to working
with you to address the ocean and coastal issues raised in this
hearing. I would be happy to answer any questions that you may have.
Senator Cantwell. Thank you, Admiral Watkins. Thank you for
your, as I said earlier, ongoing advocacy in this area.
We will start now with a round of 5-minute questions from
my colleagues. I will start off with Dr. Feely if I could,
asking you a question about this experience of acidification
that we are in now. Obviously, we have had other experiences in
the past on ocean acidification.
We obviously--I do not know if you are anticipating my
question.
[Laughter.]
Dr. Feely. If that is the question, I have a slide for you.
Senator Cantwell. I did not know I was going to ask this
question. But we obviously have had time periods before between
glacial and inter-glacial periods when we have had
acidification. So what is different now? That is my first
question. If you have a slide for that I am going to be very
surprised.
[Laughter.]
Dr. Feely. Actually, no. In the past, through the
geological past, the CO2 levels have been much
higher than we have seen now, perhaps 20 million years ago or
even farther back. The difference is that the organisms that
are responding to the acidification respond to the saturation
state of sea water, which is a combination of the
CO2 concentrations and the pH change and the calcium
changes.
It turns out that in our present condition calcium
concentrations are lower than they have ever been in geological
history. So therefore the saturation state that we are looking
at occurring in the future is going to be lower than has ever
been observed in the geological past. This is being influenced
directly by the CO2 increases that we are observing.
So these ecosystems will be looking at a lowered saturation
state that has not been observed through the entire history of
the oceans.
Senator Cantwell. So how should we look at the corrective
nature of things in the context if we were able to reduce
CO2 emission now how long would it take to have an
impact? How do we look at the time period if we continue for
another 10 years at the level of CO2 emissions? We
have heard from Dr. Hansen and Admiral Watkins about various
adaptive or ecosystem approaches. How do we look at what we can
do to correct this current trend?
Dr. Feely. That is very difficult to answer, particularly
because we do not have a lot of information on what the
biological tipping points are for these individual species. We
do for a select few species that have been studied in mesocosm
experiments under laboratory and bag experiments in the field.
These tipping points suggest that by the middle of this century
the coral reef systems will be severely impacted by the
increasing CO2 levels in the oceans.
The concern that we have is in the ocean itself, the reefs
are not only influenced by these simple relationships that we
just determined in the laboratory, but also other impacts such
as erosion, storm effects, and perhaps the tipping points that
we measure in the laboratory do not show and represent what the
organisms see in the field.
So what we dearly need is experiments that occur in the
field that are representative of field conditions, as well as
continuing experiments in the laboratory. Our best projections
right now are that for coral reef systems we may be seeing
severe impacts as soon as 2050 or earlier.
Senator Cantwell. Dr. Kruse, how do you as an expert in
fisheries management, how do you deal with this information? I
mean, are you working into, with salmon or Bering Sea species,
are you working factors of climate change and acidification
into the management plans for fisheries? How do you address
that if, as Dr. Feely says, we do not have all the data, but we
know that we are starting to see impact?
Dr. Kruse. Thank you for your question. In the North
Pacific Fishery Management Council, we are making some really
pretty good progress to incorporate climate variability into
fish stock assessments and fishery management. One of the ways
that scientists are doing that, for example, is they have found
that the catchability of the trawl used to survey of certain
species is very highly dependent on temperature. So they have
done experimentation both in the field, but also modeling
studies, that have identified the nature of that relationship.
So they are incorporating that into stock assessments.
Also, with the Bering Sea pollock, which is probably the
best assessed fish stock that we have in our system, there has
really been some excellent studies relating the dynamics of
that particular population to temperature and sea ice dynamics.
So those are finding their ways into the management strategies.
Admittedly, we are really early on the curve of doing this.
In fact, soon there will be a workshop to address these issues.
I chair the Fisheries Science Committee for the PICES, the
North Pacific Marine Science Organization. A subgroup of us are
having a workshop in Seattle in July 2007 with our
international Pacific Rim colleagues to see how we can better
make these connections between climate and our fish assessment
models and our management strategies.
So we are making some progress, but certainly there is a
lot more work to be done.
Senator Cantwell. Well, I applaud the North Pacific Fishery
Management Council for its leadership in this area. I think in
the past you have showed great stewardship on environmental
issues, so I applaud that, even though it seems challenging at
this point in time.
Senator Stevens?
Senator Stevens. Thank you very much.
Mr. Doney, I am informed that the Pacific Decadal
Oscillation has shifted every 20 to 30 years and that if we
look at the past there were temperature observations that the
ocean cooled from 2003 to 2006, but over the past 40 years that
the average of all those has been that the warming trend has
resulted in a .04 degrees change Centigrade. Do you agree with
that? The increase in the temperature of the oceans has been
.04 degrees Centigrade?
Dr. Doney. Senator, I think that is a reasonable estimate
of the volume average change. That is actually a rather large
number. The heat capacity of the ocean is several thousand
times that of the atmosphere, and the numbers, the back of the
envelope calculation, is that if the integrated global average
temperature of the ocean went up by .1 degrees it would be
equivalent to the atmosphere going up by 100 degrees.
So you have to think about it in the context----
Senator Stevens. That is in terms of stored heat.
Dr. Doney. That is in stored heat.
Senator Stevens. I understand that. But in terms of the
temperature, the implication of your testimony was there has
been this overwhelming rise in the temperature of the oceans.
Is that your position?
Dr. Doney. The surface temperature has been going up about
.2 degrees per decade over the last 30 years, and if you look
at the full water column much of the heating is occurring at
the surface. As you go down the water column, the heating rates
are smaller, but they are quite large relative to the natural
background.
Senator Stevens. You disagree with that figure that I just
gave you, then, that the average for 40 years is .04?
Dr. Doney. I think it is .04 degrees Celsius over the 40
year period. That is actually quite a large number, considering
the rates that the ocean heats and cools naturally.
Senator Stevens. Do you agree or disagree, doctor? Is that
a proper figure?
Dr. Doney. I would have to check my numbers, but I think
that is a reasonable estimate.
Senator Stevens. I have been told that we are ending the
Little Ice Age, that this period we are seeing right now is a
return to the normal situation at the beginning of that Little
Ice Age. Do you disagree with that?
Dr. Doney. I do think the paleoclimate data suggest that
the current temperatures are much higher than the temperatures
that were existing before the Little Ice Age. These are records
that are based on, for example, tree ring records and isotope
records. The best estimates of the climate over the last
thousand years show that the 50-year period we are in now is
warmer than at any time in the last 1,000 years.
Senator Stevens. How long do you think the Little Ice Age
lasted?
Dr. Doney. The Little Ice Age was a couple hundred years.
So we are certainly experiencing much warmer climate than
existed prior to the Little Ice Age.
Senator Stevens. Would you check that, please, because that
is not my information.
Dr. Doney. I can check that for you, sir.
Senator Stevens. Let me ask Admiral Watkins. I think I
agree with everything you said. The difficulty is the funding.
Since 2001 the Congress and this administration has allocated
$29 billion just to climate-related science alone. There may be
some question of whether those funds were spent effectively,
but that is a massive increase over the previous 6 year period.
How much more do you think we need to have?
Admiral Watkins. Senator, last year we worked with the
staff up here and members to deliver the answer to some
questions raised by the Senate, and I think you were a co-
signer on that letter.
Senator Stevens. Yes.
Admiral Watkins. We worked very hard on that to come up
with what do you need, what are we talking about here? We came
up in that report, ``From Sea to Shining Sea,'' that the Senate
acted on last year, at least in one case, and that was
Magnuson-Stevens Reauthorization Act. That was a good product
that came out of that.
That was the Senate. You had to push it through the House.
We have not had any support from the House on funding. In fact,
the Senate has had to restore every year for the last 5 years
significant cuts by House Appropriations, coming over here with
NOAA getting a $500 million cut, and you have had to restore it
all.
So we have spent all our time restoring to status quo. And
our report said status quo ain't good enough. We have got to
start making the investment in science. We have got to start
getting serious about organization and structural changes of
how we deal with an ecosystem-based approach that cuts across
jurisdictional lines both in the White House and up here and in
the states. And we still have not done anything. So it has been
3 years now.
So I am just saying I count on the Senate because the
Senate has been the only receptive body, and we have not put
enough money in. We said $750 million over 2007 appropriated is
the right kickstart, and to do that for the next 4 or 5 years
to try to buildup to about $13 billion----
Senator Stevens. I wanted that in the record. $750 million,
if we had that increase by that amount over 5 years----
Admiral Watkins.--over 5 years that would do everything we
recommended in our report, and that would include the climate
change issue.
Senator Stevens. Madam Chairman, I have a conflict. May I
ask one more question?
Senator Cantwell. Yes.
Senator Stevens. Dr. Kruse, I do appreciate your coming, as
I indicated. I want to know this. I am told, and as a matter of
fact you said in your own testimony here today that is printed,
that the North Pacific temperatures warmed between 1920 and
1940. Do we have any records to show what happened to king crab
and other species during that time? Did they shift northward
during that period, that 20 years of warming? Can we show--when
the temperature went down, were they restored naturally?
Dr. Kruse. Thank you, Senator Stevens, for your question.
That is really an excellent question. Unfortunately, as we go
back in time we find we just do not have the routine stock
assessments that we have now. For example, in the Bering Sea
the very first National Marine Fisheries Service bottom trawl
survey started, I believe it was 1969, and it was in a small
area of Bristol Bay, focusing on Bristol Bay red king crab.
Likewise in the Gulf of Alaska, most of our surveys started
in the 1980s or maybe in the 1970s. So we do not have the
fishery-independent information to really objectively look at
that question. If you look at fisheries data, you always have
to be careful because catch rates can be affected by fishing
practices and there may not be a direct reflection to what the
populations are doing.
In the Kodiak area, for example, those fisheries did not
begin until the late 1950s and really got under way in the
1960s. King crab catches peaked in 1965. So we just did not
have observations prior to that time.
There were, however, some fishermen who were fishing for
other species who claim that in the earlier time period it was
very rare to find king crab. So it is anecdotal information
that lends support that crab populations were down.
Senator Stevens. Did those peaks follow the temperature
curve, is what I am getting at? Have they followed the
temperature curve? There seems to be a 20 year up and 20 year
down in the North Pacific. Have the peaks in our species
followed that curve?
Dr. Kruse. The short answer is some of them do and some of
them don't. I spend a lot of time with colleagues examining
crab population dynamics and some crab populations seem to be
related to temperature signals. The northern shrimp that had
supported a big fishery in Alaska is more clearly related to
temperature, particularly in the North Atlantic. But it is
difficult to simply connect temperature to king crab population
dynamics. It is much more complicated.
Senator Stevens. I thank you. I have overstayed my leave. I
saw a chart just recently that showed that the CO2
spike was very small compared to the spike in methane. We have
now got enormous amounts of methane being released from the
permafrost in Russia and in the Arctic. Has anyone examined
this? Is that going to affect the oceans at all as the methane
continues to increase?
Dr. Kruse. I have not done that. It is not my area.
Dr. Doney. I will take a shot at that. Molecule for
molecule, methane is about 20 times or 30 times more potent as
a greenhouse gas than CO2.
Senator Stevens. Why have we not measured that, then?
Dr. Doney. Actually, there is a global network that NOAA is
part of that measures methane, and there are actually quite
good measurements.
Senator Stevens. I mean in relation to the oceans.
Dr. Doney. The effect of methane on the oceans is, as I
mentioned in my testimony, is one of the other greenhouse gases
that is leading to increased warming. The methane doesn't
dissolve in the ocean, so most of its impacts are through
increased warming.
Senator Stevens. Thank you very much.
Senator Cantwell. Dr. Feely, did you want to respond to
that too?
Dr. Feely. I just wanted to add that when methane is
released into the oceans it quickly oxidizes to CO2
by bacterial processes. So the impacts that we see in the
oceans are the oxidation product of CO2.
Senator Stevens. Resulting from the increase in methane?
Dr. Feely. When methane is released, for example from
sediments or from methane hydrates, it quickly gets oxidized to
CO2 by methane-oxidizing bacteria. So the impacts
that we would see in the oceans would be the CO2
enrichment.
Senator Cantwell. Thank you.
Senator Klobuchar?
Senator Klobuchar. Thank you, Madam Chair.
I just wanted to follow up, Dr. Doney, on some of the
questions that Senator Stevens was asking about the temperature
issue, just to clarify this. I am also on the Environment
Committee and I get questions about this kind of thing a lot. I
always use the example for the air temperature that it has gone
up one degree in the last century and the EPA predicts it will
go up 3 to 8 degrees in this coming century. To give some
perspective to people, because especially in Minnesota we
think, well, in the middle of the winter that does not sound
that bad, but I give them the perspective that since the Ice
Age it has only gone up 5 degrees, the height of the Ice Age,
the temperature worldwide.
So I wondered if you could use that kind of analogy with
the ocean temperatures in some way to better clarify this for
us, when you said that it was actually a large amount to go up
.04.
Dr. Doney. Right, and I also wanted to make one additional
clarification, which is there were some early reports that
global ocean temperatures had started to drop around the year
2002. But when they went back and reexamined the data, they
found that they had been making errors in the way they had been
treating some of the data. The most recent estimates are that
the ocean temperatures leveled off or cooled slightly but there
has not been a significant, long-term drop since the
observational record began.
Yes, the ocean changes that we are seeing are unprecedented
in the historical record and are comparable to what was seen
during the deglaciation from the last glacial period. You have
to remember, though, when you are talking about the temperature
change of 5 degrees between the glacial maximum and what we
call the Holocene, the modern period, that occurred over
several thousand years. We are experiencing the same
temperature change over decades, and that is what I mentioned
in my testimony that it is not just the magnitude of the
change, it is the rate of change that species cannot adapt to.
Senator Klobuchar. Thank you.
One of the things I get asked about is the effect that this
has had on the severity of storms with the warming of the
ocean. Does anyone want to lend some expertise to that issue?
Dr. Doney. I will try to answer that. There is some data
that suggests that the intensity of tropical storms has been
increasing for things like hurricanes and typhoons. There is
still not clear evidence whether the frequency of storms will
change. There are good theoretical reasons to believe that
storms will increase in intensity because warmer air can hold
more water, and the whole process of the energetics of warmer
sea surface temperatures and warmer atmospheres holding more
water should lead to stronger storms, both in the tropics, but
also at mid-latitudes, which could lead to not just effects in
the ocean, but effects on land like increased flooding.
Senator Klobuchar. I mentioned the Great Lakes earlier in
my opening comments and I just wanted to put something out
there because I am not sure we will have a hearing entirely
devoted to the Great Lakes and climate change. But as I
mentioned, the water in Lake Superior is lower, and there are
studies out of the University of Minnesota at Duluth and other
places showing that part of this, the opposite of the oceans
where it is going up, is that because we have less ice because
of the increasing temperatures and so the water is evaporating,
and it is having an actual tremendous effect on the economy up
there.
Just to give you a sense, in 2006 at just one terminal dock
in Duluth it took 42 more ships to load the same amount of
tonnage as it did in 2005 because of the fact that we are
seeing a lowering of the water level in the Great Lakes. I
always look for examples to use for some of my colleagues that
are in states that are not on the coast areas, to use about why
the climate change issue is affecting us just as it is
affecting people in the coastal areas.
I know that this was not the focus of this hearing, but if
anyone had any information to add to the information we are
gathering on the Great Lakes that would be helpful. Dr. Feely?
Dr. Feely. Yes. I just wanted to add, the same problems
that we are talking about with ocean acidification should be
also thought about with respect to the Great Lakes. The Great
Lakes are lakes that are not as well buffered as the oceans, so
the impacts could be even more severe. To my knowledge there
has been very few studies of this particular problem.
Historically, we have looked at acid rain in the Great Lakes
regions and acid rain is very similar to this kind of problem
because it involves sulfuric acid and nitric acid and those
kinds of impacts are usually quite severe and short-lived over
the seasonal changes due to snow melt and its impacts on rivers
and lakes.
This is a different kind of problem because it is a gradual
increase in CO2 over a long period of time. So we
should look at these kinds of issues with respect to the Great
Lakes as soon as possible.
Senator Klobuchar. Madam Chair, could I do one more
question or are we running out of time?
Senator Cantwell. No, absolutely ask additional questions.
I thought perhaps, though, given your question, I think that
Dr. Feely's slides are about acidification and acidification
impact. Would now be a proper time to show that?
Dr. Feely. Sure, I would love to.
Senator Klobuchar. Very good. We have been waiting to see
this slide.
[The PowerPoint presentation is retained in Committee
files.]
Dr. Feely. I actually prepared this slide for this
presentation. What we have done with the global CO2
surveys, we made measurements in the 1990s of the distribution
of anthropogenic carbon in the ocean and we used that
information to develop models of how the oceans will change
over time with respect to saturation levels that the coral reef
systems and the pteropods and many of these calcifying
organisms are sensitive to.
Then we worked together with the modelers who had been
working with global circulation models. This is a composite
model output of the 13 best models throughout the world that
have been used for these studies. What this map shows is the
pre-industrial level of saturation state for the oceans in the
surface waters. What we have plotted on here in the map in the
very black dots are the present day distributions of tropical
coral reefs. The magenta dots are the present day distributions
of the deep water coral reefs.
What the tropical coral reefs need is a saturation state in
excess of 3, a saturation state of 3 for them to survive
naturally. We do not know what the saturation state requirement
is for deep water corals because those studies have not been
done.
So we move into the present condition in 2000 and we see
that the system has changed. It is no longer optimal for
calcification, but many of the regions are still safely within
that saturation state of 3. We would prefer to have it at 3.5
or 4. Again, most of the tropical coral reefs are within that
state. But we see we are now encroaching on that optimal
saturation state.
If we go out to 2040, we see that now the coral reef
systems in the Hawaiian Islands region and other locations are
also very, very close to being well within this limit of 3.0
saturation, and therefore there is some concern whether they
can continue to calcify by 2040.
The magenta regions here are the thermodynamic limit where
dissolution begins to occur, and we can see that occurring in
the southern ocean by 2040.
When we go out to 2100, what we see is that the entire
world oceans are no longer within this level of 3.0, which
means that the coral reef systems would not be able to continue
to calcify. Again, the entire southern ocean would be a region
of complete dissolution. In other words, no organism would be
able to calcify. They would begin to dissolve.
Now we see in the North Pacific, high northern latitudes,
also in the Atlantic particularly and presumably the Bering
Sea, we have the same conditions of undersaturation in which
the coral organisms and the other calcifying organisms would--
--
Senator Cantwell. But Dr. Feely, on calcification, you are
treating that like an indicator species? Or should we attribute
other----
Dr. Feely. Calcification is the process by which they form
their shells. So the question is can they form their shells or
not? What these models show is where they can form their shells
and when the shells will actually begin to dissolve.
Senator Cantwell. You are treating that as, you are
treating that like any other indicator species as to the health
of an environment, or are there other implications we should
draw from that, I guess as you keep going through this?
Dr. Feely. Yes. Well, for example, for coral reefs, this
means whether they can continue to produce their skeletons. But
for other species, this would suggest that they would no longer
be able to calcify. For example, the pteropods which are the
primary food source for salmon would no longer be able to form
their calcium carbonate shells. So these are the regions where
they would have to be--no longer can exist in those locations.
So they would be removed from those locations. So the food
chain would change dramatically.
Senator Cantwell. So you are saying they are the beginning
of the food chain indication?
Dr. Feely. Right.
Senator Cantwell. Is that what you are saying?
Dr. Feely. That is exactly correct.
Senator Cantwell. OK.
Dr. Feely. So what we are seeing, this process of
CO2 enrichment really starts from the poles and
moves toward the tropical regions. So the high latitude
regimes, the high productivity regimes for fish and shellfish,
are going to be affected first, and this is what we are seeing
in these model outputs.
Senator Cantwell. Thank you very much.
Senator Klobuchar?
Senator Klobuchar. I think Dr. Hansen wanted to comment a
little more.
Dr. Hansen. I wanted to add something with regard to the
Great Lakes. The Great Lakes have not only, as well as the
world's oceans, have not only an issue of quantity--as you
stated, the world's oceans are growing, while the lakes are
shrinking--but also issues of water quality. In the Great Lakes
region you have not only the issue of increased evaporation
because of altered ice cover, but you also have periods of
drought that have been occurring there.
Coupled with that drought are altered use of fertilizers
and pesticides for agriculture and other human adaptations, if
you will, to the changes that are already going on. And as part
of that, I think that one of the concerns for the Great Lakes
should be how is the water quality being protected under that
changing climate regime and how do we rethink the way we set
regulatory limits on things like contaminants, sewage outflow,
in response to the fact that there is now less water in that
water body that historically has been receiving those outputs.
Senator Klobuchar. Thank you.
My last question was for you, Admiral Watkins. As we looked
at all the enormous challenges we are facing, you had some
ideas for solutions, and obviously some of it is the funding
for research. But I was interested in your idea of the more
integrated management of our ecosystem and if you could just
spend a little time explaining that to us as we look at how we
can better do things in addition to the additional funding.
Admiral Watkins. Well, let me say first, Senator, that I do
not know if you noticed, but when we put out our draft report
in the spring of 2004 the biggest negative comment we had on
that draft was from the Great Lakes area saying, it is oceans,
coasts, and Great Lakes. We agreed and you will see it in our
report. It is not only what we just heard here, but also
invasive species are coming in there and destroying the
fisheries.
Senator Klobuchar. The Asian carp.
Admiral Watkins. It is a huge issue. If you ask the White
House, what are you doing you will hear: Look, we have
established a task force, we have got a Federal to State
relationship, we have got the Canada-Great Lakes Commission, it
has been there for many, many years. And the answer is: Yes;
what have you done? And the answer is not very much.
So it is like everything else. It is a lot of rhetoric and
very little substance to the investment that we need in the
Great Lakes. But it is part of the whole regime that we are
talking about here. We are saying that we need to have a
governance response and we need to have a science response, and
both of those come into play for the Great Lakes.
On the governance side, we have mentioned to Congress in
our reports we need to codify and strengthen NOAA. That should
be a pigh priority of this Committee to pass a NOAA Organic
act. NOAA should focus on three core functions: assessment,
prediction, operation; research and education; and marine
resource and area management; a realignment that would benefit
the Great Lakes.
Congress should also request a National Academies study to
make organizational recommendations for a national climate
change response office. That could deal with the Great Lakes
issue. It should also require an integrated budget in support
of the national climate change response office.
This Committee, members of this Committee here and other
committees, sent a letter 2 years ago to the White House
saying, we want an integrated ocean policy budget submission.
If you want to send them up this way, from 15 agencies, that is
fine, but horizontally integrate them and get them up here, so
we can tell; are you doing anything. So far we have not seen
such a budget, so the answer is no, they are not doing
anything. So it is all superficial stuff.
So again, the Great Lakes get affected by all that.
We say codify and strengthen the White House Committee on
Ocean Policy. Could this work in the current system? Yes. All
the President would have to say is: Do it, Mr. OMB, and do it,
Mr. Adviser, the Policy Adviser. That happened to me when I was
Secretary of Energy. I wanted to clean up the bomb factory
after 40 years when the Cold War ended. It was President H.W.
Bush who said: No, Mr. Secretary of Defense, I know it is
coming out of your hide, but we are going to do it. We went
from $800 million a year to $6 billion. Now it is $7 billion.
We are turning Rocky Flats back to the State of Colorado,
Fernault back to the State of Ohio.
So we can work with the current system if we want to do it.
So it really starts in the White House. I think if they took
the lead the Congress would respond very positively.
So then we want to codify the Committee on Ocean Policy, to
prevent it from disappearing, since it currently exists under
an executive order. That is how NOAA was established via an
executive order, and we do not want that any more. We want
Congress to codify NOAA to give them responsibility,
accountability, and resources. Of the $750 million a year over
JOCI recommended, about 60 percent of that would go to NOAA, to
support all the projects that we have outlined in our report.
So that addresses the governance issue. On the science
side, we say fund the climate-related research priorities in
the administration national ocean research priorities plan.
They have a plan that was released in January. Fund it. And you
know, in the initial funding for the plan they allowed NASA to
refuse funding to support its Earth sciences. So I do not trust
implementation of that plan solely by the Administration. So
Congress has to codify it and say: No, we expect it to do its
job.
Fund the Integrated Earth Observing System. We have heard
that here today. We have got to have a comprehensive
observation system. We have got to know what is going on out
there. And we can build on that. It is 50 percent completed
now, but not in the ocean. There is not even close to 50
percent there. We are way down at the bottom of the heap in
terms of our science, technology, data management, ability to
convert data into useful product.
Senator Cantwell. Admiral Watkins, if I could jump in here,
are you suggesting that we incorporate the oceans impact when
we are talking about setting a target for CO2
emissions reduction? And if we were, how would you do that?
Admiral Watkins. Well, the Oceans Commission was never
tasked by the Congress to do that. We are on the fringes of it
because we kept running into the time. But we could not address
it. So we did not feel we had the mandate out of Congress to
deal with greenhouse gas mitigation. Obviously, as Secretary of
Energy when I was there we did. We ran some of the ocean flux
studies. We ran the carbon cycle. We put a lot of emphasis in
this.
I think it dissipated at that point. So I have some
personal views on it, but I do not have any clues as to--you
know, there has been so much talk about this, to give a
specific number and set these. I am on the same wavelength as
some of the witnesses this morning on doing both mitigation and
adapting, and adaptation. We have not addressed the subject of
adaptation at all and that is sad, because for the next two and
a half decades, no matter what we do with greenhouse gas
reduction, we are going to have a problem of global warming. It
is there for us to deal with and we have got to manage our way
through it. So we need both.
Senator Cantwell. Well, let us turn to Dr. Feely on that so
we can understand, because I think that the Fiscal Year 2008
budget would decrease about 14 percent from the 2006 level
research related to acidification. Is that correct?
Dr. Feely. Yes, Senator, that is correct.
Senator Cantwell. And we do not have any money for
adaptation?
Dr. Feely. Well, the research that is presently being
provided for directly funding ocean acidification research is
about $1.6 million per year throughout all the Federal
agencies. There is an additional $4 million per year that is
being funded within NOAA on related activities to ocean
acidification, but they are not directly funding ocean
acidification research.
We draw from that additional related research to identify
and proceed on ocean acidification studies. But they are not
directly funded for doing ocean acidification studies.
Senator Cantwell. You have suggested, I think, four themes.
One would be--in this research realm. One would be monitoring.
Another would be understanding the response of the animals to
acidification, ecosystem modeling, and risk assessments.
Dr. Feely. That is correct.
Senator Cantwell. So do you have a sense of how much that
would cost in the context of where we are today and where we
need to get a clear picture of ocean health and a plan?
Dr. Feely. Well, we have discussed this in a number of
workshops that involve the scientists that are doing ocean
acidification research and related activities. In those
workshops, the community has indicated that a national program
on the order of $30 million per year would be appropriate.
Senator Cantwell. Dr. Hansen, did you--in best practices on
adaptation, what do you think are the key things that we should
be looking at?
Dr. Hansen. Well, the first thing is that we actually need
the capacity to do this type of work. We are not training
people to do this work whatsoever. We are also not raising the
awareness of people that it needs to be done. Many people are
still trying to pretend that climate change either is not
happening or someone else is taking care of it. Unfortunately,
it is a reality for all of us.
So the sort of steps that I have laid out in my testimony
and that my colleagues and I have been talking about is first
the need to train the next generation of people who will be
taking this on, as well as getting ourselves up to speed on it;
developing some sort of extension agency that actually is going
out, raising awareness about this issue, engaging people on
what the options are, getting them to implement them, and
taking the lessons back to synthesize and provide the next
generation of guidance.
Then finally, we need to be incorporating climate
adaptation into literally everything that is being done in
national and local and international legislation, quite
frankly, where we are preparing all of the projects we are
working on so that they are climate-prepared, be it in coastal
infrastructure, preparing it for sea level rise, be it
agriculture, preparing it for periods of drought or movement of
pest species, forestry, preparing for increasing fire regimes,
fisheries, preparing for movement and new management
strategies.
Literally every sector of our society is and will continue
to be impacted by climate change for decades to come, and we
are grossly underprepared for that.
Senator Cantwell. Dr. Kruse, it seems that you are kind of
on the front lines there in Alaska with the polar bears and
walruses and seals being impacted by melting ice. What can
managers do on these species?
Dr. Kruse. Thank you for your question. Certainly these
climate changes are out of the purview of fisheries managers,
but fisheries managers need to deal with the ramifications. So
one of the clearest things we can do is be more precautionary.
So if there is potential for fishery interactions with either
of those species directly or indirectly through their prey
base, I think we have to be more precautionary.
As I indicated briefly in my oral remarks and more fully in
my written remarks, the North Pacific Fishery Management
Council is looking at establishing perhaps an Arctic Fishery
Management Plan that would basically set those areas off
limits, particularly with an eye toward the loss of sea ice.
The loss of sea ice reduces habitats for the ice seals and
polar bears. Associated with the loss of sea ice, we may see a
switch from that system, which is a more benthic system that
support prey of birds like the spectacled eiders and walruses
to a pelagic system. Realizing that these changes are
happening, maybe it is best to not allow any fishing there.
At their next meeting in June 2007, the North Pacific
Fishery Management Council is looking at defining what we call
essential fish habitat. They will consider basically freezing
the northern boundary of the current areas that are being
fished in the Bering Sea, even realizing that fish may move
north, into previously unfished areas wtih increasing
temperature. The problem is that we simply do not have data nor
surveys up there, so we do not know what is there, and we
realize that these northern ecosystems can be very fragile with
respect to species, such as some of the seabirds, the marine
mammals. Certainly the coastal residents of those northern
areas make use of those marine resources and really depend on
them for their survival.
So being more precautionary I guess is the short answer.
Senator Cantwell. Dr. Conover, do we have to take this into
consideration in implementing the Magnuson-Stevens Act?
Dr. Conover. Yes. I think one of the most important shifts
that we are seeing in how we manage marine resources is to take
a more ecosystem-based approach. In an ecosystem-based
approach, then the impacts of climate change can be folded into
the decisions we make about how heavily we can harvest various
species or whether we need to back off.
A lot of the things we see happening in my region of the
world go beyond just the impacts of harvesting and include
diseases, the impacts of water quality, hypoxia, and all those
end up having an impact on the abundance of the species we are
trying to protect. So using an ecosystem approach, which really
we have only begun to do recently, lends itself to thinking
longer term rather than year to year, and including
expectations of climate change in that approach.
Senator Cantwell. Admiral Watkins, I am going to give you
the last word, with the emphasis on ``last.'' But if you could
briefly, what do you think that we need to change from a policy
perspective? Why from a political sense are we not getting this
done? What are the road blocks and what do you suggest that we
do to take the information we have had to date at this hearing
and integrate that into policy action?
Admiral Watkins. Well, you used the term here ``ecosystem-
based management.'' That is not a trivial issue. Eyes roll back
when you tell that to the public, but in Washington we know
what it means. It means major reorganization of how we do
business here. Horizontal integration across Federal agencies,
up here on the Hill and so forth becomes very important when
you get into climate change practices. We cannot separate these
things. So we have to kind of back away from the old way of
doing business, take advantage of the information technology
world we live in, bring business and industry into the game to
help us build these architectural systems that we want to
observe, get the database straightened out, be able to convert
that data to useful products at the local, county, State
levels.
We should be able to do all this, but the current
governance regime is a big hindrance right now. There is no
process to integrate activities across the Federal Government.
That is what we have got to deal with. That is why we put so
much emphasis on governance. It is not that governance will
answer everything. Obviously, you have to have a budget and you
have to have educational programs. You have to have a lot of
things. But if we are going to spend the money right, we better
do it right, and we better do it the way nature does it. We
fouled it up by managing it piecemeal, vertically. Nature
beautifully integrates horizontally and tells us what the
problem is. And we need to listen to that, and then we need to
manage within the natural process, and we are not doing that
today at all.
So that is why I put so much emphasis on governance. And
obviously the science is the other critical component. We have
not put adequate emphasis on it. When the President announced
his new American Competitiveness Initiative two years ago in
the State of the Union Address, oceans were not in the game.
They are not even considered in this.
So we have not put emphasis on science, in particular,
ocean science. The Office of Science and Technology Policy also
used to be the Science Adviser to the President. He is no
longer the Science Adviser to the President. It was removed. Is
science important to the administration or not? I do not think
so, not sufficiently important, particularly when you get into
this area of climate change.
So we have got a major job to do in the way we look at
this, and that is why, because the Senate has been so receptive
to our work over the last few years, we are kind of counting on
the Senate to take the lead. We tried the White House and we do
not get enough response. I do not know that Jim Connaughton is
not doing a decent job, but he is not given the time of day and
the strength to put the money into the budget process, to give
you a budget up here that is other than what we have always
done.
I will say the administration this year in the 2008 budget
finally put in a figure that was comparable to the 2007
appropriated. They have never done that before. So is that a
plus? Well, yes, I guess so, but not a big plus.
Senator Cantwell. We will stop on that note.
Admiral Watkins. Anyway----
Senator Cantwell. Because we all do want to work together,
and I appreciate your point. You had the scientists nodding at
the other end of the table about how we should look more at the
environment and its response from a systematic perspective.
I will point out that I think the Pacific Northwest,
particularly Washington State, has done fabulous work on two
areas, timberfish and wildlife, which is industry working
together with environmentalists. In fact, those ecosystem
plans, if they are ever challenged, you get the industry
officials as aggressively responding as you do the
environmentalists. So I think it has been a good measure. I
think Bill Ruckelshaus has done fabulous ecosystem work as it
relates to salmon recovery in the Northwest, again working with
a whole cadre of local governments, Native Americans,
fishermen, industry officials across the board. So we may be a
little bit more of a forerunner on that.
And as I mentioned, the Pacific Northwest Fishery Council I
think has been a forerunner in implementing environmental
impacts and management into their fisheries policy ahead of the
rest of the Nation. So we obviously do care greatly about our
environment in the Northwest, including our ocean.
So I want to thank all the panelists for a very detailed
presentation about the challenges that we face with our oceans
policy. Admiral Watkins, I hope that my colleagues will review
all of this. Obviously, we are going to leave the record open
for additional questions. If you could help us and comply by
answering that in a quick fashion, we will leave the record
open for a few weeks. But I hope my colleagues will take this
hearing and take the testimony and take up the baton that you
are passing to us to act and to consolidate this as part of our
response to healthy oceans.
So thank you all very much. We are adjourned.
[Whereupon, at 11:52 a.m., the hearing was adjourned.]
A P P E N D I X
Prepared Statement of Hon. Daniel K. Inouye, U.S. Senator from Hawaii
Coral reefs have been called ``the rainforests of the sea.'' In
addition to their great beauty, they offer critical habitat to a
variety of marine organisms. Coral reefs cover less than 1 percent of
the Earth's surface, but they provide resources and services worth
approximately $1.4 billion annually to the U.S. economy. In the State
of Hawaii, the economic value of coral reefs is estimated at more than
$360 million annually.
These diverse coral habitats have survived for millions of years,
recovering from natural disturbances. However, the reefs are under
threat from rising ocean temperatures and increasing ocean acidity.
Scientists are observing coral bleaching that is more widespread and
more severe, in some cases, severe enough to kill the corals.
I am pleased the Administration is proposing legislation to
reauthorize and strengthen the Coral Reef Conservation Act of 2000,
legislation that I introduced in 1999 to establish the Coral Reef
Conservation Program within the National Oceanic and Atmospheric
Administration.
However, this legislation will not be effective in protecting coral
reefs if we do nothing to reduce carbon emissions.
Coral reefs are just one of the kinds of living marine resources
that are impacted by climate change. Scientific research has confirmed
that emissions of greenhouse gases contribute to climate change and
that such emissions are causing our oceans to become warmer and more
acidic. These effects are harming our living marine resources. The
science is also clear that these impacts will grow worse as long as we
continue to do nothing to reduce greenhouse gas emissions.
Therefore, I hope that our distinguished panel members will be able
not only to help us understand these impacts, but also to suggest a way
forward.
______
Prepared Statement of Hon. Frank R. Lautenberg,
U.S. Senator from New Jersey
Madam Chairman, thank you for holding today's hearing.
Despite the Bush Administration's ongoing efforts to censor and
suppress science, there is no doubt that man-made global warming is
real, and it threatens the health of our planet, including our oceans.
The increase in carbon dioxide causes global warming and ocean
acidification.
NOAA researchers predict that oceans will continue to acidify to
``an extent and at rates that have not occurred for tens of millions of
years.'' Ocean acidification threatens our marine ecosystems. As the
chemistry of our ocean changes, some marine life may not be able to
survive.
Acidic water damages our corals, for example, which provide vital
habitat to many marine species, and plankton, the foundation of the
marine food chain.
In addition, the rise in ocean temperature has caused some fish to
move to colder waters, posing challenges to our commercial and
recreational fisheries.
The combined effects of global warming and ocean acidification
cannot be ignored. The potential environmental and economic cost to New
Jersey--and coastal states across the country--is too great.
I am concerned that the Administration is not taking the issue of
ocean acidification seriously enough. In the Magnuson-Stevens bill we
passed last year, Congress directed the National Research Council to
report on ocean acidification and its impact on the United States. I
have requested funding for this authorized study as a member of the
Appropriations Committee, and I will work with my colleagues to see
that the effects of ocean acidification are made a priority for this
Administration.
Thank you again Madam Chairman for beginning our work on this
important issue.
______
Response to Written Questions Submitted by Hon. Daniel K. Inouye to
Scott C. Doney, Ph.D.
Question 1. Coral reefs are not just critical habitat for fish. In
my state of Hawaii, they are also an economic engine supporting both
fishing and tourism. Is ocean acidification or the increase in sea
temperature the more pressing issue for protecting and preserving
Hawaii's coral reefs and other marine resources and why?
Answer. Surface ocean warming and acidification are two sides of
the same coin because their root cause is the same, namely the human-
driven rise in atmospheric carbon dioxide. Therefore we need to address
both issues simultaneously. Warming has already been linked to coral
bleaching events. Acidification has been shown to limit coral growth in
the laboratory, and more work is needed to assess the impacts on whole
ecosystems. One concern is that the combined effect of temperature and
warming may be much more harmful on coral reefs than either factor in
isolation. Thus it is difficult to separate temperature and
acidification effects and to assign one factor or the other as the most
pressing issue; they are both important.
Question 2. How can we incorporate actions to address these issues
into an overall management strategy for protecting Hawaii's corals and
other marine resources?
Answer. Climate warming and acidification are global processes that
are not easy to reverse at the local or state level (see below).
Management strategies, however, can be developed to minimize their
impacts on coral reefs and fisheries. The first step is to reduce the
negative effects of other factors that are more amenable to local
control. These include things like pollution, land runoff of excess
nutrients, over-fishing, and habitat destruction. The second step is to
create more adaptive, forward-looking management strategies that
explicitly include climate warming and acidification in their design.
For example, the catch limits for many fisheries are set based on
historical levels of fish stocks. But the future ocean will not look
like the past. Numerical climate models will provide some guidance for
helping resource managers, but at present there remain relatively large
uncertainties in our forecasts of the magnitude in climate change on
regional scales and resulting biological responses. Following a
precautionary principle, one strategy would be to lower present catch
limits to provide an additional safety factor for unforeseen climate
impacts and to closely monitor resource levels to maintain
sustainability. Climate change and ocean acidification also need to be
factored into the design of other management tools such as marine
reserves or marine protected areas. For example, as species
distributions shift with climate, will the size of a protected area be
sufficient and will it still protect the target species of interest.
Question 3. Dr. Doney, could you tell me what adaptation and
mitigation steps you think the United States needs to take to address
the threats that climate change and ocean acidification pose to our
ocean resources?
Answer. Increasing surface water temperatures and ocean
acidification are driven by the human emissions to the atmosphere of
greenhouse gases like carbon dioxide. The atmosphere mixes on time-
scales of months to a few years, and the climate impact of carbon
dioxide emissions is global rather than local. Thus ocean warming and
acidification require global solutions to limit the rise in atmospheric
carbon dioxide. The most direct mitigation steps would be to reduce the
amount of carbon dioxide released to the atmosphere. Reducing emissions
can occur through shifts to non-fossil fuel energy sources, increases
in energy efficiency, and deliberate actions to sequester carbon rather
releasing it to the atmosphere. One of the more promising sequestration
approaches appears to be storage of carbon dioxide in geological
reservoirs, such as old natural gas and oil fields. There are also
proposals to manipulate land and ocean ecosystems to remove some of the
excess carbon dioxide in the atmosphere and increasing carbon storage
plants, soils and the deep ocean. Adaptation strategies are discussed
in the answer above.
______
Response to Written Questions Submitted by Hon. Maria Cantwell to
Scott C. Doney, Ph.D.
Question 1. The most rigorous mitigation goal in the recent summary
report by the Intergovernmental Panel on Climate Change is to stabilize
atmospheric greenhouse gas levels between 445 and 710 parts per million
by 2030. But given that the current concentrations of atmospheric
carbon are estimated at 379 parts per million, shouldn't this target be
set at a much lower level if we are to effectively address climate
change? What is the expected temperature increase of this range?
Answer. The IPCC stabilization scenarios from the 4th IPCC
Assessment report are discussed in some detail in the Technical Summary
for Working Group III (Mitigation). I think the specific values of 445
to 710 parts per million are drawn from Table TS. 2 (page 21 and 22 of
the draft Technical Summary); the same table is given as Table SPM.5 on
page 23 of the Summary for Policymakers. This table is somewhat
confusing as it lists two columns of carbon dioxide (CO2)
levels, one an actual CO2 level and the other the
``equivalent'' CO2 level, that is the amount of
CO2 that would be needed to match the total radiative
warming of excess CO2 plus the other human driven greenhouse
gases (methane, nitrous oxide, chlorofluorocarbons, etc.).
(numbers from Table TS. 2; IPCC 4th Assessment, Technical Summary,
Working Group III)
------------------------------------------------------------------------
Equilibrium
Equivalent temperature
Category CO2 (ppm) CO2 (ppm) change
(deg. C)
------------------------------------------------------------------------
I 350-400 445-490 2.0-2.4
II 400-440 490-535 2.4-2.8
III 440-485 535-590 2.8-3.2
IV 485-570 590-710 3.2-4.0
V 570-660 710-855 4.0-4.9
VI 660-790 855-1,130 4.9-6.1
------------------------------------------------------------------------
The most extreme stabilization scenario is for stabilizing roughly
present day conditions (CO2 of 350-400 ppm; equivalent
CO2 of 445-490 ppm) by 2100. This is a very rigorous goal
and would require reductions of all greenhouse gas emissions by 2015
and net removal of CO2 by some means (e.g., growing biomass)
toward the end of the century. A series of stabilization scenarios are
then presented that allow for higher atmospheric CO2 (and
equivalent CO2 because of the other greenhouse gases).
Two different temperatures are often reported for stabilization
scenarios, the transient temperature at some point in time along a
pathway and the equilibrium temperature. Even once atmospheric
greenhouse gas levels are stabilized, the planet will continue to warm
for an extended period of time. The temperature differences given above
are for the equilibrium global mean temperature. Equilibrium
temperature changes relative to pre-industrial levels are estimated by
IPCC to range from 2.0-2.4 deg. C for the most aggressive stabilization
scenario (marked I in the table above). The temperature increases grow
as higher stabilization CO2 levels are allowed, reaching
4.9-6.1 deg. C for the most lenient case examined. Even these values
are considerably less than some business as usual scenarios considered
in IPCC.
Question 1a. What would be the impacts on our ocean resources if we
were to reach these emissions levels?
Answer. Even if we were to eliminate all greenhouse gas emissions
to the atmosphere, the ocean and the planet would experience some
additional amount of warming and acidification beyond current levels
(global mean temperature increase of 0.76 0.19 deg. C and
surface pH drop of -0.1 units) because of the inertia in the climate
system. Even the most aggressive IPCC stabilization scenarios lead to
further warming and acidification beyond what we have already
experienced (see above). Broadly speaking, there is a strong consensus
that reducing the total amount of climate change will lessen the
impacts of climate change and acidification on ocean resources. For
some specific ecosystems we can make estimates of the trends such as
reductions of some species and increases in others, poleward shifts in
the ranges of warm-water species, further degradation of coral reef
systems, etc. Making more detailed, quantitative forecasts for
biological systems comparing the impacts for one stabilization scenario
versus another is more difficult at present because of uncertainties in
our scientific understanding. Biological systems are not linear, and it
is likely that at least for some regions with larger climate change and
acidification ecosystems will reach thresholds beyond which there will
be significant and dramatic changes in ocean resources. Equally
important is the rate at which the changes are occurring. Faster rates
of climate change and acidification give species less time to adapt or
to migrate to different regions where conditions may be more favorable.
Faster rates of change also introduce additional social and economic
problems, particularly when significant changes happen over a time-
scale short relative to the lifetime of infrastructure used for a
particular ocean resource (e.g., fishing fleets).
Question 2. How can we improve our ocean and Earth observation
programs to ensure understanding of the impacts of global climate
change and ocean acidification on the marine environment?
Answer. The U.S. and other countries are putting in place elements
that will contribute to a global ocean observing system, but there
remain a number of gaps in such a system. First, much of the current
in-water observing network measures physical properties of the ocean.
Documenting ocean physical changes is key, as physical changes drive
biological changes. But there needs to be a corresponding rapid
expansion of in-water chemical and biological properties. In some
cases, we need to invest in the development and testing of new sensors
to routinely measure seawater chemistry and biology. For example, there
is an international network that uses volunteer observing ships (cargo
freighters, research vessels) and some moorings to measure surface
ocean carbon dioxide levels. Given concerns with ocean acidification,
that network needs to be expanded in scale (e.g., by using autonomous
drifters and profiling floats) and in scope by including pH
measurements.
Second, the U.S. needs to maintain and extend the capability to
monitor ocean trends from space using satellite-based remote sensing.
For ocean biology, sensors measuring ocean color, a proxy for surface
water phytoplankton chlorophyll, have been invaluable in understanding
biological spatial patterns and dynamics on time-scales from seasonal
to multi-year. We will soon have 10 years of data from the NASA and
GEOEYE SeaWiFS sensor. The future of U.S. ocean color remote sensing
and other routine satellite ocean measurements is somewhat in doubt
with the transition of many measurements from NASA research mode to an
operational mode under NPOESS by NOAA and DOD. In particular, the
requirements for long-term climate data records (e.g., consistency
across time and across satellite platforms) can be more demanding than
those for operational needs, and it is not clear that the appropriate
investments are being made within NPOESS.
Question 3. What are the potential impacts of some of the currently
proposed climate change mitigation strategies on the marine
environment--such as iron stimulated plankton blooms or injection of
CO2 into sea sediments?
Answer. Ocean iron fertilization has been proposed as a carbon
mitigation strategy because phytoplankton growth is limited by the
availability of the trace nutrient iron in some oceanic regions. As
indicated by the results from about a dozen deliberate experiments,
adding iron causes the plant-like phytoplankton to bloom, drawing down
seawater carbon dioxide levels. What is not clear, however, is the
long-term fate of the newly formed organic matter. If this material is
converted back to carbon dioxide in the surface ocean by respiration,
the net effect on ocean carbon storage will be small. If on the other
hand some of the carbon is transported to the deep ocean, iron
fertilization could act to sequester carbon and lower atmospheric
carbon dioxide levels.
Several concerns have been raised about the potential impacts of
iron fertilization:
1. To be effective, iron fertilization must alter ecosystem
dynamics, and the environmental consequences on other parts of
the food web are not well understood. For example, how will
iron fertilization effect fisheries? Will it increase the
likelihood of harmful algal blooms? Because of ocean
circulation, the environmental impacts of iron fertilization
may arise either locally near the fertilizationsite or non-
locally downstream.
2. Iron fertilization may stimulate the production and release
to the atmosphere of other climate greenhouse such as nitrous
oxide and methane. Since these gases are much more potent
greenhouse gases on a per molecule basis, the release of these
gases may greatly decrease the effectiveness of iron
fertilization as a mitigation approach.
3. Increased carbon export to mid and deep-ocean could decrease
subsurface oxygen levels, increasing the size of oxygen minimum
zones.
Two other proposed carbon mitigation strategies include direct
injection of carbon dioxide into the deep ocean water column or into
deep-sea sediments. Deep-sea sediment injection would have local
impacts on benthic (bottom) and water-column ecosystems because of the
infrastructure required for injection. If the leakage of carbon dioxide
into the overlying seawater can be minimized, the environmental
consequences on the ocean water column will be relatively small. Direct
injection of carbon dioxide into the ocean deep waters will result in a
lowering of seawater pH and ocean acidification. Locally around the
injection site the resulting acidification will be much larger than
that observed in the upper ocean. Extrapolating from studies of surface
species, one should expect significant negative impacts on calcifying
species (deep-sea corals, mollusks). Some studies suggest only minimal
acute (short-term) effects on fish; less clear are the longer-term,
chronic effects. There will also be local dissolution of carbonate
bottom sediments. Some injection schemes involve pumping down liquid
carbon dioxide, which is heavier than seawater and will form
concentrated pools along the ocean bottom. Benthic life will be
destroyed underneath the liquid carbon dioxide pools, but the effected
area would be considerably smaller than if the carbon dioxide were
dispersed in the seawater. The environmental impacts will depend upon
the extent to which the liquid carbon dioxide mixes into the overlying
seawater.
______
Response to Written Questions Submitted by Hon. Frank R. Lautenberg to
Scott C. Doney, Ph.D.
Question 1. According to NOAA, about 4,000 species of fish,
including approximately half of all federally-managed fisheries, depend
on coral reefs and related habitats for a portion of their life cycles,
and the National Marine Fisheries Service estimates that the value of
U.S. fisheries from coral reefs exceeds $100 million. Will corals and
plankton be able to survive or adapt to more acidic waters in our
oceans?
Answer. Our current information on the impacts of ocean
acidification is based almost entirely on short-term (days to months)
studies of shell forming plants and animals to large increases in
carbon dioxide. Higher CO2 will affect other organisms (non-
shell forming plankton, juvenile fish, etc.) but there is considerably
less data on non-calcareous (shell forming) organisms. Most of the
experiments to date have been conducted either in the laboratory or in
small controlled conditions (for example, outdoor seawater tanks or
floating tethered bags filled with seawater). The observed effects of
acidification include decreased calcification rates (slower shell-
formation), reduced growth rates, and in some cases reduced
reproduction rates. Extrapolating from those results to the ocean,
where the rise in carbon dioxide will be more gradual, involves
considerable uncertainties.
The ability of calcifying organisms to survive or adapt to high
CO2 conditions likely varies from group to group. Some types
of organisms, such as phytoplanktonic coccolithophores, have species or
ecotypes that can survive without a calcareous shell, and under high
CO2 conditions the population may shift toward the non-
calcareous variants. The shells of other groups of calcareous organisms
such as pteropods (planktonic marine mollusks) and most corals appear
to be integral to their life history. Most organisms experience
variations in seawater chemistry naturally due to seasonal cycles and
year to year variability. It is not well known the degree to which
organisms may possess mechanisms to adapt to small levels of
acidification or the extent to which those mechanisms would be
effective (even over decadal time-scales) against the significant
levels of acidification projected by the middle to end of this century.
A recent study (Fine and Tcernov, Science, Vol. 315, page 1811, 2007)
showed that a Scleractinian coral species could grow as individual
polyps without shells at high CO2 levels; while this
demonstrates survival to acidification, the ecological impact of these
naked polyps would be dramatic as they no longer would contribute to
reef formation.
Question 1a. If they cannot, what are the implications for other
marine species and the ocean's food chain?
Answer. Calcareous organisms are important components of ocean food
webs, and the reductions in calcareous organisms due to acidification
likely will have broad ecological effects. The gradual build-up of
warm-water coral skeletons produces reefs that provide habitat for some
of the richest marine ecosystems on the planet. The size of reefs
reflect a dynamic balance between calcium carbonate production that
adds to the reef and loss processes (storms, human reef destruction,
etc.) High CO2 conditions will likely shift the balance and
may cause a reduction in the size of reefs. Similar decreasing trends
for cold-water corals would result in habitat loss on the continental
shelf and slope in temperate to polar latitudes. Planktonic calcareous
organisms play important roles as prey for larger species. For example
pteropods (small planktonic snails), which are abundant in the North
Pacific and Southern Ocean, are eaten by fish (e.g., salmon) and baleen
whales. At present it is not clear how the impacts of acidification
will filter through the rest of the ecosystem and whether and how
predator species will adjust to the loss calcareous prey.
Question 1b. Species have migrated in response to ocean temperature
changes. Will marine organisms migrate to avoid acidification?
Answer. The ranges for calcifying species are expected to shift in
response to acidification. Most experiments show that organisms are
sensitive to the carbonate ion concentration and the saturation state
for carbonate minerals, both of which decrease as pH declines. Seawater
carbonate chemistry varies with temperature, and under present
conditions saturation decreases as one moves poleward. Under a high
CO2 world, species ranges therefore would have to shift
equatorward to maintain the same saturation state. In contrast, global
warming will drive species ranges poleward. One concern is that the
opposing forces of warming and acidification will eliminate the
combined temperature and saturation state niches to which some
organisms are adapted.
Question 2. There have been ocean acidification events in the past
that have resulted in the disappearance of marine organisms, including
corals. What does the fossil record reveal about the adaptation of
marine organisms to changes in ocean acidification?
Answer. Several different lines of geological evidence suggest that
ocean seawater carbonate chemistry has varied in the past in response
to alterations in atmospheric carbon dioxide levels and variations in
the weathering rates on land and deposition rates of carbonate minerals
in the ocean. Several processes buffer (damp) ocean pH variations on
the gradual time-scales of several thousand to several hundreds of
thousands of years that characterize many geological changes. The
current rate of ocean acidification is many times that of prehistoric
rates and because of the slow time-scales of ocean buffering the pH
changes over the next several centuries may be much larger than those
experienced throughout most of the geological record. Ocean pH levels
have already dropped by 0.1 since the preindustrial period, comparable
to the pH change thought to have occurred between glacial and
interglacial cycles, and an additional pH decrease of 0.14-0.35 may
occur by the end of this century.
Past analogues to present acidification may have occurred in
several catastrophic events in the geological record where it appears
that large amounts of carbon dioxide were released rapidly into the
atmosphere-ocean system, resulting in ocean acidification and dramatic
reductions in marine carbonate burial. The more extreme episodes are
associated with minor to major biological extinction events, which
because of the way the geological time-scale was originally developed
using paleofossils, often fall at the boundaries of geological periods.
A number of hypotheses have been proposed (e.g., isolated refuges) for
why some species (or groups of species) survive these acidification
events and others do not, but the exact reasons are not well
understood.
Question 2a. How long did it take for corals and other marine
organisms to recover from the acidification events in the past?
Answer. The recovery time-scales to past geological events most
likely were determined by both biology and geochemistry. One of the
best documented events occurred during the Paleocene-Eocene thermal
maximum (PETM) about 55 million years ago. The PETM is marked by rapid
increases in temperature and alterations in the ocean carbonate system
over about 1,000 to 10,000 years followed by a more gradual relaxation
over several hundred thousand years. A large acidification event throws
off the balance of alkalinity input and removal from the ocean, and the
hundred thousand year relaxation timescale can be explained as the
amount of time required for the ocean alkalinity cycle to come back
into balance through carbonate and silicate weathering on land. There
is only a limited fossil record to reconstruct what happened to
calcifying organisms during the PETM because carbonate sediments are
not buried under acidic conditions. Following the PETM, there was a
biological radiation of calcifying organisms.
Question 3. Dr. Feely indicates in his statement that ``the
atmospheric concentration of carbon dioxide is now higher than
experienced on Earth for at least 800,000 years and is expected to
continue to rise*the oceans are absorbing increasing amounts of carbon
dioxide . . . and the chemical changes in seawater resulting from the
absorption of carbon dioxide are lowering seawater pH.'' Have
scientists determined a dangerous level of pH that we need to avoid?
Answer. A report from the German Advisory Council on Global Change
(WBGU) recommends that the surface seawater pH decrease from
preindustrial conditions be limited to 0.2 pH units or less on scales
of either individual ocean basins or the global average (Schubert et
al., 2006). Estimates are that surface pH has already decreased by 0.1
since the preindustrial (30 percent drop in H+
concentration); a pH drop of 0.2 would result in a 60 percent decline
in H+ concentration. Lower pH increases the solubility of
calcium carbonate minerals (aragonite and calcite) making it more
difficult for marine organisms to make shells, and the rationale used
by Schubert et al., 2006 is that we should avoid a pH drop large enough
to drive aragonite understaturated in surface water (aragonite is the
more soluble mineral form used by corals and pteropods). The 0.2 pH
criteria is set by the surface waters of the Southern Ocean, which are
already close to undersaturation.
R. Schubert R., H.-J. Schellnhuber, N. Buchmann, A. Epiney, R.
GrieBhammer, M. Kulessa, D. Messner, S. Rahmstorf, J. Schmid, 2006: The
Future Oceans--Warming up, Rising High, Turning Sour, Special Report
from German Advisory Council on Global Change (WBGU), ISBN 3-936191-14-
X, http://www.wbgu.de 110 pp.
Question 3a. At the current rate of carbon dioxide emissions, how
long will it take for the oceans to reach a dangerous level of pH?
Question 3b. Have scientists determined at what level of carbon
dioxide concentrations we need to maintain in order to avoid this
dangerous level of pH?
Answer. Few model simulations have been run with constant present-
day emissions so question b) is a little difficult to answer directly.
Rather most model simulations have been conducted either with either
IPCC scenarios of carbon dioxide emissions or atmospheric carbon
dioxide stabilization trajectories. Orr et al., 2005 report that the
0.2 pH criteria would be reached and wide-spread aragonite
undersaturation would occur in the Southern Ocean with IPCC business as
usual emission scenarios between 2060-2075. Based on scenarios to
stabilize atmospheric carbon dioxide by 2100, Calderia and Wickett
found that a carbon dioxide stabilization target of 540 ppm would lead
to a global surface pH drop of 0.23, exceeding the 0.2 criteria. A
carbon dioxide target of 450 ppm would lead to a global drop of 0.17 pH
units.
Caldeira, K. and Wickett, M.E. Anthropogenic carbon and ocean pH.
Nature 425, 365 (2003).
Orr, J.C., V.J. Fabry, O. Aumont, L. Bopp, S.C. Doney, R.A. Feely,
A. Gnanadesikan, N. Gruber, A. Ishida, F. Joos, R.M. Key, K. Lindsay,
E. Maier-Reimer, R. Matear, P. Monfray, A. Mouchet, R.G. Najjar, G.-K.
Plattner, K.B. Rodgers, C.L. Sabine, J.L. Sarmiento, R. Schlitzer, R.D.
Slater, I.J. Totterdell, M.-F. Weirig, Y. Yamanaka, and A. Yool, 2005:
Anthropogenic ocean acidification over the twenty-first century and its
impact on marine calcifying organisms, Nature, 437, 681-686, doi:
10.1038/nature04095.
Question 4. In light of the latest findings published last month in
the journal Science in which the biological consumption and
remineralization of carbon in the ``twilight zone''--a zone in the
ocean where some sunlight reaches but not enough for photosynthesis to
occur at ocean depths between about 660-3300 feet--actually reduces the
efficiency of sequestration (Buesseler, et al., Science 316, 567,
2007). What does this mean for the future of carbon sequestration in
our ocean if carbon is recycled back into the surface ocean and
atmosphere faster than originally thought?
Answer. Ocean scientists have known for several decades that much
of the particulate organic matter that sinks out of the surface layer
is consumed in the mesopelagic (300-3,300 feet depth in the ocean). One
metric used to evaluate this consumption is the respiration or
remineralization length-scale, a measure of how vary down the water
column an average particle sinks before it is consumed and the organic
carbon turned back into dissolved inorganic carbon. The Buesseler et
al., study in Science magazine examined two regions, a low productivity
region off of Hawaii and a higher productivity region off Japan. They
deployed a new instrument (a floating sediment trap) that should
reduces biases in estimates of sinking particle flux. The major new
contribution of the paper was to better elucidate that the length-scale
for organic carbon differs from region to region. The length-scale near
Hawaii was quite short (most of the sinking material was consumed in
the upper water-column, while the length-scale off Japan was longer (a
larger fraction of the material sank deeper in the water column).
So far the experiment has been conducted at two sites and for
relatively short periods of time (a few weeks). The findings do not
necessarily imply that organic carbon is recycled shallower in the
water column than was previously thought as the results from the two
sites bracket the standard length-scale estimate derived from previous
studies. These results do have implications for ocean biological carbon
sequestration strategies in that in order to compute the effectiveness
of a fertilization experiment, one likely needs to better understand
both the surface water and subsurface ecosystems.
Question 4a. Do scientists know how much carbon sequestered to the
deep ocean is being overestimated?
Answer. The Buesseler et al., results do not change global average
estimates of the carbon consumption rate with depth, which have been
computed on large-scales (entire ocean basins) by geochemical
techniques; the findings do suggest that there may be more spatial and
temporal variability in the effectiveness of consumption.
Question 4b. How has this changed what scientists think about how
long carbon dioxide will be naturally sequestered and how long it will
take material to resurface from the twilight zone?
Answer. More field data from a diverse set of locations (and over
the full seasonal cycle) will need to be collected before this question
can be addressed with any confidence. Currently the results bracket
prior estimates and thus there is no immediate reason to think that our
present understanding of the ocean carbon system is too greatly wrong.
The Buesseler data does suggest that there is great spatial and
temporal heterogeneity in remineralization length-scales. Such data may
also help us better characterize the underlying mechanisms driving
subsurface organic matter consumption, and important factor if we are
to understand how the ocean carbon system may change with evolving
climate.
Question 5. It is essential to start a global research and
monitoring program for ocean acidification. We should be utilizing the
observing systems already in place including the undersea research
program. What are your recommendations for utilizing the current
infrastructure of ocean observing systems and satellites to monitor
ocean acidification?
Answer. The current ocean observing system has only limited
capabilities to monitor ocean acidification directly but can be
enhanced with targeted investments. At present there is a large in-
water observing system to measure ocean physical variables. For
example, the Argo global array of profiling floats of greater than
2,800 instruments now routinely measures temperature and salinity of
the upper 1,000 meters (3,300 feet) of the ocean. There is an
international network that uses volunteer observing ships (cargo
freighters, research vessels) and some moorings to measure surface
ocean carbon dioxide levels. But the spatial and temporal coverage is
much more restricted than the physical observing network, any many
cases pH is not measured directly, and the measurements are typically
limited to the upper few meters of the water column. The U.S. and
international CLIVAR CO2 and Repeat Hydrography Program
surveys subsurface pH and ocean carbonate variables but on only a
limited number of transects and on a time-scale of one occupation of
each transect approximately every 10 years. Even larger gaps exist for
monitoring pH in coastal waters, where the requirements for high
density measurements are great because there are larger variations in
space and time. There are pilot efforts underway within NOAA Coral Reef
Watch program to instrument several coral reefs for routine that would
serve as a model for other regions. Given concerns with ocean
acidification, the ocean network of chemical and biological
measurements needs to be expanded in scale (e.g., by using autonomous
drifters and profiling floats) and in scope by including pH
measurements and other relevant variables related to biological
responses to acidification (e.g., calcification rates; particulate
calcium carbonate concentrations, etc.). To do this, we need to invest
now in the development and testing of new sensors to routinely measure
seawater chemistry and biology on autonomous platforms.
Satellite remote sensing cannot measure ocean pH directly but does
provide a host of valuable information for assessing ocean
acidification and its biological impacts that complements the
information available from in-water sensors. Satellite sensors can be
used to locate and access the size of coral reefs. Blooms of planktonic
coccolithophores (a phytoplankton group with calcium carbonate shells)
can also be measured from space under some conditions. Satellites
provide a regional context for in-water measurements because satellites
often measure ocean properties over a wider window in space and time.
Data analysis methods are also being developed for estimating surface
water chemistry based on empirical relationships with physical and
biological variables that can be measured from space (e.g.,
temperature, chlorophyll) or estimated from ocean numerical models. The
U.S. needs to maintain and extend the capability to monitor ocean
trends from space using satellite-based remote sensing. For ocean
biology, sensors measuring ocean color have been used to map the
occurance and distribution of coccolithophore blooms from space. We
will soon have 10 years of data from the NASA and GEOEYE SeaWiFS
sensor. The future of U.S. ocean color remote sensing and other routine
satellite ocean measurements is somewhat in doubt with the transition
of many measurements from NASA research mode to an operational mode
under NPOESS by NOAA and DOD. In particular, the requirements for long-
term climate data records (e.g., consistency across time and across
satellite platforms) can be more demanding than those for operational
needs, and it is not clear that the appropriate investments are being
made within NPOESS. We also need to extend the capabilities of ocean
remote sensing with new sensors focused on detecting changes in the
ecological community (which species are present) and plankton
physiology and targeting coastal and coral reef environments, which
require high spatial resolution.
Question 5a. What information can be gained from monitoring natural
variations over a long time period of time and in several different
oceanic regions?
Answer. Ocean pH and related environmental conditions vary
naturally in time (event scales such as storms, seasons, year to year
variability) and in space (because of changes in temperature, upwelling
of subsurface carbon rich water, and biological photosynthesis and
carbon drawdown). A better understanding of the magnitude of those
changes and the resulting biological responses is critical to
unraveling the mechanisms by which acidification impacts ocean
ecosystems. Consistent long term records of pH trends and biological
responses (e.g., calcification rates) would provide data to evaluate
and test the climate models used to make future forecasts. More robust
models would provide increased confidence to the decisionmakers and
stakeholders using these forecasts. Better monitoring also would allow
scientists to identify the environmental conditions under which
calcifying organisms grow today and the extent to which present
acidification and natural variations are already impacting calcifying
organisms and whole ecosystems. Together with targeted laboratory
experiments and field process studies, a monitoring network will help
elucidate the ability of organisms to adapt to acidification and the
changes that will occur to other parts of the ocean food web if
calcifying organisms are harmed by acidification.
Question 6. This year I requested funding through the
Appropriations Subcommittee on Commerce, Justice, Science to fund the
National Research Council report on ocean acidification mandated by
Magnuson-Stevens Fishery Conservation and Management Reauthorization
Act. Has NOAA yet identified the compelling research needs for this
study?
Answer. I am not aware that NOAA has finalized the scope of the
proposed National Research Council report on ocean acidification, and
if they have done so the research needs have not been made widely known
to the public.
Question 6a. If so, what are the research needs for this report?
Answer. One concern is that if not properly framed the NOAA
sponsored NRC report could be too narrowly focused solely on the needs
and mission of a single agency (NOAA) and neglect the opportunities
offered by an integrated, multi-agency strategy for ocean
acidification. The U.S. scientific community has devoted considerable
thought and effort into defining the most compelling and urgent
research needs with regards to ocean acidification. These research
needs are well articulated in a recent report from a workshop sponsored
by the NSF, NOAA, and USGS (Kleypas et al., 2006). The recommendations
of this report on the major scientific issues that should be pursued
over the next 5-10 years include:
``Determine the calcification response to elevated
CO2 in benthic calcifiers such as corals (including
cold-water corals), coralline algae, foraminifera, molluscs,
and echinoderms; and in planktonic calcifiers such as
coccolithophores, foraminifera, and shelled pteropods;
Discriminate the various mechanisms of calcification within
calcifying groups, through physiological experiments, to better
understand the cross-taxa range of responses to changing
seawater chemistry;
Determine the interactive effects of multiple variables that
affect calcification and dissolution in organisms (saturation
state, light, temperature, nutrients) through continued
experimental studies on an expanded suite of calcifying groups;
Establish clear links between laboratory experiments and the
natural environment, by combining laboratory experiments with
field studies;
Characterize the diurnal and seasonal cycles of the
carbonate system on coral reefs, including commitment to long-
term monitoring of the system response to continued increases
in CO2;
In concert with above, monitor in situ calcification and
dissolution in planktonic and benthic organisms, with better
characterization of the key environmental controls on
calcification;
Incorporate ecological questions into observations and
experiments; e.g., how does a change in calcification rate
affect the ecology and survivorship of an organism? How will
ecosystem functions differ between communities with and without
calcifying species?
Improve the accounting of coral reef and open ocean
carbonate budgets through combined measurements of seawater
chemistry, CaCO3 production, dissolution and
accumulation, and, in near-shore environments, bioerosion and
offshelf export of CaCO3;
Quantify and parameterize the mechanisms that contribute to
the carbonate system, through biogeochemical and ecological
modeling, and apply such modeling to guide future sampling and
experimental efforts;
Develop protocols for the various methodologies used in
seawater chemistry and calcification measurements.''
Kleypas, J.A., R.A. Feely, V.J. Fabry, C. Langdon, C.L. Sabine, and
L.L. Robbins, 2006. Impacts of Ocean Acidification on Coral Reefs and
Other Marine Calcifiers: A Guide for Future Research, report of a
workshop held 18-20 April 2005, St. Petersburg, FL, sponsored by NSF,
NOAA, and the U.S. Geological Survey, 88 pp.
Question 7. About one-third of all man-made carbon dioxide
emissions are absorbed into the ocean. However, at a certain point the
oceans may no longer be able to absorb carbon dioxide at the same rate.
If this happens, warming of the atmosphere will increase even more
rapidly. Are we close to seeing the rate that the oceans absorb carbon
dioxide slow down to a point that our global temperatures increase even
faster?
Answer. Several factors may decrease the future effectiveness of
the ocean sink for anthropogenic carbon dioxide. The chemical buffer
capacity of seawater decreases as the levels of inorganic carbon
increase. Warming reduces the solubility of carbon dioxide. Surface
warming and increased vertical stratification are also expected to slow
ocean circulation, which will reduce oceanic carbon dioxide uptake.
Carbon dioxide uptake would also decline if the ocean deep-water
circulation in the North Atlantic were to slow dramatically. In
numerical models, most of these factors decrease ocean carbon dioxide
uptake rates gradually with time. Some effects are already being felt,
and their influence will grow with time with global warming and rising
atmospheric carbon dioxide.
Question 7a. How does temperature affect the rate at which ocean
acidification occurs?
Answer. The dominant factor in ocean acidification is the increase
in the amount of dissolved inorganic carbon in seawater. Some
researchers have explored the impacts of climate change on ocean
acidification, finding relatively small impacts relative to the signal
from increasing dissolved inorganic carbon. Temperature plays a key
role in determining the chemical impact of acidification. The
saturation state of carbonate minerals in seawater depends on
temperature. The saturation state of colder waters starts off lower
than in warmer waters and will become under-saturated with respect to
carbonate minerals before warmer waters.
Question 7b. The Arctic Ocean is becoming warmer and fresher which
may slow down thermohaline circulation. What are the implications of
these changes on ocean acidification?
Answer. Climate change is expected to warm and freshen the surface
ocean in the Arctic and reduce sea-ice cover. The increased vertical
stratification will reduce the transport of anthropogenic carbon
dioxide into intermediate and deep-waters in the Arctic, reducing the
influence of ocean acidification in mid- to deep-waters. In contrast,
reduced sea-ice will enhance surface gas exchange, surface water levels
of anthropogenic carbon dioxide and acidification.
Question 7c. How does the increase in atmospheric carbon dioxide
and subsequent warming affect atmospheric and oceanic circulation? Will
the increase in atmospheric and ocean temperatures result in more
frequent El Nino's and intense hurricane seasons?
Answer. This a wide-ranging and complex question at the heart of a
large research effort on climate change research within the U.S. and
internationally. A broad-brush picture of the expected changes in ocean
and atmosphere circulation are given in the 4th IPCC Assessment Report
that was recently released (IPCC, 2007). A major factor is that global
warming of the surface ocean will inject more water vapor into the
atmosphere, strengthening the planetary water cycle and potentially
providing more energy for storms. The Arctic and land surfaces will
warm faster than the ocean, altering the temperature gradients that
drive atmospheric circulation and winds. The Arctic will experience a
reduction in sea-ice cover, particularly in summer, and a general
warming and freshening of surface waters. Warming of the upper-ocean
and inputs of additional freshwater at high latitudes will tend to
increase vertical stratification of the upper water column and slow
exchange between surface and subsurface water masses. Altered wind
patterns will also change the location and strength of coastal and
open-ocean upwelling.
According to the Summary for Policy Makers for Working Group I, the
following more specific trends are expected:
heat extremes, heat waves and heavy precipitation events
will become more likely;
tropical cyclones (hurricanes and typhoons) will likely be
more intense with larger peak wind speeds; there is still
considerable debate about whether the number of tropical storms
will change;
the stormtracks for extratropical storms are likely to move
poleward, altering precipitation patterns;
the amount of precipitation will likely increase at high
latitudes and decrease at subtropical latitudes; the latter may
exacerbate subtropical droughts;
the meridional overturning circulation and deep water
formation in the Atlantic will likely decrease but it is very
unlikely to undergo an abrupt transition over this century.
There is less confidence in predictions of expected changes in
ocean and atmosphere circulation on more regional scales because the
model forecasts differ from climate model to climate model.
Question 7d. Which ocean regions will be first to experience large
changes in carbonate chemistry? How long before large changes occur?
Answer. The entire surface ocean is already experiencing changes in
carbonate chemistry, and these trends will increase approximately in
step with rising atmospheric CO2 concentrations. When
anthropogenic CO2 dissolves in seawater it decreases pH,
increases the partial pressure of carbon dioxide (pCO2), and
increases the concentration of dissolved inorganic carbon (DIC, the sum
of all of the different inorganic forms of carbon dioxide, carbonic
acid, and its acid-base dissociation products). Except in regions of
seasonal and permanent ice-cover, the positive trend in surface water
pCO2 and DIC appears to approximately track the rise in
atmospheric CO2 levels following solubility equilibrium
relationships. The magnitude of the pH change depends upon the
buffering capacity of seawater; more rapid pH changes occur in colder
waters and waters with higher DIC and pCO2 levels for the
same size incremental addition of carbon dioxide.
The penetration of the anthropogenic carbon dioxide signal into the
subsurface ocean is controlled by ocean circulation. The concentrations
of anthropogenic carbon and perturbations to pH tend to decrease as one
looks down the water-column. About half of all the anthropogenic carbon
dioxide is found in the upper 400 m ( 1,200 feet) of the water column.
Elevated levels of anthropogenic carbon are found below that depth in
the lower thermocline (400-1000 meters depth) below the surface water
convergence zones of the subtropical gyres and Southern Ocean.
Anthropogenic carbon is also observed below the thermocline in and
downstream of intermediate and deep-water formation regions in the
northern North Atlantic and Southern Ocean.
Question 8. How will lower calcification rates, due to an increase
in ocean acidification, higher ocean temperatures, and changes in
nutrients affect ocean carbon chemistry and carbon export rates?
Answer. Acidification will tend to reduce the calcification in the
upper ocean, the sinking flux (export) of particulate inorganic carbon,
and the remineralization of particulate inorganic in the subsurface
ocean. The effect of acidification on total biological productivity in
the surface ocean may be about neutral, as it is likely that non-
calcifying organisms may be able to replace calcifying phytoplankton
populations that are diminished due to acidification. Organic carbon
export to the subsurface ocean via sinking particles is not directly
proportional to biological productivity, but depends upon the
composition of the food web. Organic matter has a density similar to
seawater, and there is evidence indicating that heavier ballast
materials, such as carbonate shells, increase organic matter sinking
rates. The impact of reduced calcification on the export of organic
carbon in the open ocean is less certain, but may also result in a
reduction in export.
Reduced inorganic export has the opposite effect as reduced organic
carbon export on surface water chemistry and air-sea carbon fluxes. The
formation of organic matter lowers seawater dissolved inorganic carbon
(DIC) and lowers the partial pressure of carbon dioxide
(pCO2), which governs the air-sea gas exchange of carbon
dioxide. A reduction in organic matter export, therefore, would reduce
the effectiveness of the biological pump and act to increase surface
water and atmospheric CO2 thus accelerating climate change.
The formation of calcium carbonate (CaCO3) or calcification
in surface waters lowers both seawater DIC and alkalinity (a measure of
the acid-base balance of seawater). For each mole of CaCO3
removed, DIC drops by 1 mole and alkalinity drops by 2 moles. Somewhat
counter intuitively, calcification increases pCO2 because
the effect of the alkalinity change outweighs that of DIC. Therefore
reduced carbonate export would act to decrease surface water and
atmospheric CO2 thus helping to ameliorate climate change.
Preliminary model simulations, however, suggest that the calcification-
alkalinity feedback mechanism provides only a small brake on increasing
atmospheric carbon dioxide due to fossil fuel combustion.
Question 9. What are the expected changes to the biological pump--
the process which transports carbon throughout the ocean--due to the
increase in carbon dioxide and what will be the consequences of these
changes?
Answer. Rising atmospheric carbon dioxide has two major effects on
the ocean biological pump, altered ocean physics and ocean
acidification. The impact of ocean acidification is addressed in the
answer to question 8 above. Ocean physics will be altered because of
carbon dioxide induced global warming and other changes in physical
climate. Surface warming globally and larger freshwater inputs at mid-
to high-latitudes will increase the vertical stratification of the
water column.
Many areas of the tropical and subtropical ocean are nutrient
limited, and increased vertical stratification may decrease the supply
nutrients to the upper ocean. In these areas, biological productivity
and the sinking of organic particles, which drives the biological pump,
may drop because of the reduced nutrient supply. One possible
complication is nitrogen fixation; most organisms cannot use nitrogen
gas, but a small number can convert nitrogen gas into an organic form
that is broadly usable. Nitrogen fixation is enhanced in warm,
stratified waters and may increase in the future under climate warming.
Phytoplankton in some regions at mid- to high-latitude is currently
light-limited because of deep mixing. Biological production and
particle export may be enhanced in these areas because warming and
freshwater inputs will reduce vertical mixing rates and thus light
limitation. Model projections suggest that global ocean productivity
may not change substantially.
Question 10. Fossil-fuel use is also increasing the amounts of
nitric and sulfuric acid deposition in the oceans. How will these
elements alter surface seawater alkalinity and pH?
Answer. Fossil fuel combustion releases reactive nitrogen and
sulfur to the atmosphere. Some fraction is deposited to the surface
ocean as nitric and sulfuric acid, which reduces surface seawater
alkalinity. Agriculture releases reactive nitrogen that is deposited to
the ocean as ammonia. Because of biogeochemical transformations, the
ammonia input also leads to a reduction in ocean alkalinity. The
changes in surface seawater chemistry will lead to lower seawater pH
levels.
Question 10a. Will the impacts of these elements differ in coastal
waters versus open ocean and how may they affect marine ecosystems?
Answer. The effects depend upon the deposition rates of reactive
nitrogen and sulfur, which are highest in coastal regions and open-
ocean areas downwind of the major source regions in eastern North
America, western Europe, and south and east Asia. The effects of
acidification from reactive nitrogen and sulfur deposition will be
similar to that caused by oceanic uptake of fossil-fuel carbon dioxide.
Coastal regions may be more vulnerable to elevated acidification
because of other human perturbations (local pollution, nutrient runoff,
overfishing). Reactive nitrogen deposited from the atmosphere will also
stimulate ocean photosynthesis because nitrate and ammonia are
nutrients. Similar to excess nitrogen from river and groundwater
runoff, the resulting nutrient fertilization (eutrophication) may lead
to low oxygen zones and blooms of harmful algae.
Question 11. During the hearing a question was raised regarding the
global average increase in ocean temperature of 0.04+ C. It is well
known that the largest increases in ocean temperature are in the
surface waters and this plays a large role in the Earth's heat budget.
Can you please explain how significant the warming has been in the
surface waters and what the implications have been for increased sea
surface temperature as it relates to hurricane intensity, El Nino,
drought, and other extreme weather events? Can you highlight different
regions that have experienced large increases in surface water
temperature and how much the surface waters have warmed?
Answer. Ocean warming is indeed concentrated in the upper part of
the water column. The global average temperature increase of 0.037 deg.
C reported by Levitus et al., 2005 applies to a depth range from the
surface to 3,000m ( 10,000 feet) for time interval of (1994-98)
relative to (1955-59). In their analysis, they also report an average
temperature increase almost 5 times as large (0.171 deg. C) for the
upper water column 0-300m ( 1,000 feet) over the time period 1955-2003.
As shown in a table below, Atlantic temperatures in the 0-300m depth
range increased faster than the global trend.
Sea surface temperature also increased at a rate comparable to or
faster than the 0-300m trend. Hansen et al., (2005) present a spatial
map of the change in sea surface temperature for the period (2001-2005)
relative to a base period of 1951-1980. They find significant areas of
the Atlantic, Indian Ocean and tropical Pacific where the sea surface
temperature increased by between 0.4 to 0.8 deg. C. Examining modern
(2001-2005) sea surface temperature changes relative to preindustrial
conditions (1870-1900) reveals warmer sea surface temperatures almost
everywhere in the ocean, with larger regions showing temperature
increases of more than 0.5 deg. C.
Higher sea surface temperatures increase the transfer of heat and
moisture from the ocean to the atmosphere. Higher sea surface
temperatures have been proposed as a mechanism for strengthening the
intensity of tropical cyclones (typhoons and hurricanes), and
variations in sea surface temperature have been linked to periods of
both drought and flooding on land. Future climate model projections
suggest that increasing sea surface temperature and climate warming
will drive increased precipitation at high latitude, decreased
precipitation in the subtropics (and possible droughts) and a general
increase in the frequency of extreme precipitation events. The link
between sea surface temperature and El Nino is somewhat more subtle as
El Nino conditions in the tropical Pacific themselves results in
elevated sea surface temperatures in the tropical Pacific and along the
West Coast of North America. Through atmospheric teleconnections, El
Nino events also alter sea surface temperatures over much of the world
ocean.
Levitus, S., J. Antonov, and T. Boyer (2005), Warming of the world
ocean, 1955-2003, Geophys. Res. Lett., 32, L02604, doi: 10.1029/
2004GL021592.
Hansen, J., M. Sato, R. Ruedy, K. Lo, D.W. Lea, and M. Medina-
Elizade, 2006:
Global temperature change, Proceedings of the National Academy of
Science, 103, 14288-14293, doi: 10.1073/pnas.0606291103.
Table T1. Change in ocean mean temperature (deg. C) as determined
by the linear trend for the world ocean and individual basins. (Levitus
et al., 2005; supplementary material).
----------------------------------------------------------------------------------------------------------------
Ocean basin Change in mean temperature 0-300 m (1955-2003) (deg. C)
----------------------------------------------------------------------------------------------------------------
World Ocean 0.171
N. Hem. 0.188
S. Hem. 0.159
Atlantic 0.297
N. Atl. 0.354
S. Atl. 0.233
Pacific 0.112
N. Pac. 0.093
S. Pac. 0.127
Indian 0.150
N. Ind. 0.125
S. Ind. 0.154
----------------------------------------------------------------------------------------------------------------
______
Response to Written Questions Submitted by Hon. Daniel K. Inouye to
Richard A. Feely, Ph.D.
Question 1. I am pleased to learn that NOAA has been working with
other agencies, including NASA and NSF, to formalize a Federal research
effort, including research on ocean acidification. Could you describe
the current Federal interagency research program and how it might be
strengthened?
Answer. While there is no formal Federal interagency research
program, NOAA and other Federal agencies (e.g., the U.S. Geological
Survey (USGS), the National Science Foundation (NSF), and the National
Aeronautics and Space Administration (NASA)) are currently in the
process of developing a formal research and/or monitoring program to
address ocean acidification. Over the past two decades, a number of
large-scale international ocean research programs have documented
global increases in the amount of carbon dioxide (CO2) in
the world's oceans. These programs, co-sponsored by NSF, NOAA and the
Department of Energy, include the World Ocean Circulation Experiment
(WOCE), the Joint Global Ocean Flux Study (JGOFS) Global CO2
Survey and the CLIVAR/CO2 Repeat Hydrography Program. The
increase in ocean CO2 concentrations and corresponding
decreases in pH levels (ocean acidification) occur in direct response
to rising levels of atmospheric CO2 and will affect some of
the most fundamental processes of the sea in coming decades. In recent
years, the rapidly emerging issue of ocean acidification has garnered
considerable interest across the scientific community, and NOAA, NSF
and NASA have been working to identify what existing capabilities can
be better tailored to monitor and understand ocean acidification. NOAA
and NSF have played an important joint role in identifying the current
extent of ocean acidification through ocean observations. NOAA has also
been involved in using environmental models to forecast ocean
acidification levels over the coming century under a variety of
CO2 emission scenarios, and has begun investigating the
possible ecosystem consequences through research studies.
Detailed in the following discussion is an overview of various NOAA
programs, technologies, and research efforts that have yielded findings
deemed relevant to ocean acidification or have recently been initiated
with the intent of addressing the many remaining uncertainties
identified by the scientific community. These examples include some
description of current Federal interagency efforts, as well as
collaboration with non-Federal/academic institutions.
NOAA Collaborative Workshops
In 2005, NOAA, USGS, and NSF jointly sponsored a workshop focused
on ocean acidification, which resulted in a report entitled Impacts of
Increasing Ocean Acidification on Coral Reefs and Other Marine
Calcifiers: A Guide for Future Research. The workshop sought to
summarize existing knowledge on ocean acidification, identify the most
pressing scientific issues, and identify future research strategies
over the next 10 years. The report concluded that ocean acidification
will significantly impact biological systems in the upper ocean with
adverse responses being observed in most organisms studied that rely on
calcium carbonate to build their skeletal structures (calcifying
organisms or calcifiers; e.g., corals). The report also identified an
extensive list of remaining knowledge gaps and research needs with
regards to ocean acidification. Among the list offered by the workshop
report was a recommendation to better characterize the carbon chemistry
on coral reefs, including long-term monitoring of the response of these
sensitive ecosystems to ocean acidification.
Observations Relevant to Ocean Acidification
Global CO2 Surveys
NOAA has contributed to several international and national research
programs that have offered important findings relevant to ocean
acidification. These programs include the World Ocean Circulation
Experiment (WOCE), the Joint Global Ocean Flux Study (JGOFS), the joint
NOAA/NSF CLIVAR/CO2 Repeat Hydrography Program, the Tropical
Atmosphere Ocean (TAO) array, and the Global Ocean Observing System
(GOOS), as well as data collected through NOAA-supported hydrostations,
mooring stations, and vessel observations. These research programs
provide the most accurate and comprehensive view of the global ocean
carbon cycle to date. NOAA funded a 5-year WOCE/JGOFS data analysis
effort that culminated in NOAA's Pacific Marine Environmental Lab
(PMEL) lead-authoring two important Science articles highlighting ocean
acidification in July 2004. While one article detailed the ocean's role
as an important sink for anthropogenic carbon dioxide, (Sabine et al.,
2004), the other described the impact that this additional carbon
exerts on the ocean's chemistry and its potential long-term
consequences for marine ecosystems (Feely et al., 2004).
Sabine et al. (2004) inventoried the amount of anthropogenic
CO2 (i.e., fossil-fuel and cement-manufacturing emissions of
carbon dioxide) that has been absorbed by the world's oceans. Results
from the inventory demonstrated that about 120 billion metric tons of
carbon as CO2 (roughly half of the fossil-fuel
CO2 released since the 1800s) has been absorbed by the
ocean. Much of this added carbon has remained concentrated in surface
waters as the mixing rate of the oceans is on the order of several
thousand years.
In addition to the WOCE/JGOFS studies, NOAA, together with the
Japan Agency for Marine-earth Science and Technology and France's
L'Institut de recherche pour le developpment, has jointly funded the
TAO array. The TAO array consists of approximately 70 moorings in the
tropical Pacific Ocean and is an important part of the Global Ocean
Observing System (GOOS). These oceanic hydrostations and mooring
systems provide temporal data that helps NOAA discern important
seasonal and decadal variability. To better ascertain the spatial
variability in oceanic carbon uptake, NOAA has collaborated with
academic partners since 1985 to outfit research and commercial vessels
with automated CO2 sensors. The intent of these observations
has primarily been to derive estimates of CO2 exchange
between the atmosphere and the surface waters of the ocean.
Fixed Buoys
As mentioned above, the TAO array consists of approximately 70
moorings in the Pacific Ocean that transmit ocean and climate data in
real-time for the purposes of tracking El Nino events. NOAA's Pacific
Marine Environmental Laboratory (PMEL) has worked closely with the
Monterey Bay Aquarium Research Institute to outfit several of these
moorings with CO2 sensors. While the coverage of these buoys
is limited to the Pacific Ocean, and therefore do not fully capture the
broad and complex system of global CO2 absorption in the
ocean, they provide consistent data that helps NOAA discern important
variability season-to-season and decade-to-decade.
In response to the 2005 ocean acidification workshop, NOAA deployed
a series of fixed buoys and augmented existing monitoring stations to
accommodate CO2 sensors deployed at a handful of U.S. coral
reefs. The NOAA Coral Reef Conservation Program, together with
researchers at the NOAA Atlantic Oceanographic and Meteorological
Laboratory (AOML) and the University of Miami, has experimented with
the deployment of commercially available CO2 sensors on NOAA
Integrated Coral Observing Network (ICON) stations at two locations in
the Caribbean. NOAA PMEL has also developed an advanced CO2
mooring system, of which four have been deployed in coastal waters.
While these observing systems are preliminary, they have offered
important insight into the CO2 variability of these waters
which contrast sharply to that of offshore waters. The CO2
measurements at one of the Hawaii moorings have been compared against
those recorded offshore at a long-term hydrostation. Similarly,
observations made in Puerto Rico have been compared against offshore
estimates derived using remote sensing. In both cases, the variability
of CO2 levels in waters overlying coral reefs is shown to be
considerably higher on daily, seasonal, and interannual scales than in
offshore waters that have typically been the focus of ocean
acidification models. Furthermore, these coastal waters consistently
have higher CO2 levels than that of offshore waters,
suggesting these systems may exceed critical levels of CO2
sooner than has been demonstrated in most ocean acidification models.
What those precise thresholds might be is an area of continued
investigation within the scientific community and NOAA will need to
collect additional data necessary to achieve any firm conclusion on the
matter.
Satellite Observations
Other observing efforts being advanced at NOAA with important
relevance to ocean acidification include the application of satellite
remote sensing to supplement ship and buoy observations of surface
ocean carbon chemistry. While ship observations provide reliable and
accurate measurements of surface ocean CO2, and offer
considerably greater spatial coverage than that provided by moored
instruments, they lack the temporal resolution of fixed platforms
(i.e., observations over time in one location) and provide relatively
limited regional coverage. Such observations can be supplemented by
satellite remote sensing. NOAA has worked to derive algorithms relating
environmental parameters that can be remotely sensed to in situ
observations of carbon measurements. NOAA continues to work to improve
the reliability and accuracy of these models and improve the data
delivery to the community. Such models are being experimentally coupled
to NOAA's ICON station CO2 monitoring network in the hopes
of deriving a tool for coral reef management to monitor the response of
coral reefs to ocean acidification.
All of these observing networks and platforms have not been
designed to specifically address ocean acidification per se, which
demands a more comprehensive measurement of ocean carbon chemistry.
Measurement of ocean acidity requires in situ technology, which NOAA is
currently testing. Such advanced observations are required to fully
model the magnitude, rate and severity of ocean acidification.
Research Efforts and Ocean Acidification
Northwest
NOAA's Northwest Fisheries Science Center (NWFSC) has begun
collaborating with the University of Washington on ocean acidification
research relevant to Pacific fisheries. In September 2006, the NWFSC
began some initial modeling studies of possible consequences of ocean
acidification on food webs. Two ongoing research projects are focused
in Puget Sound and the Northeast Pacific shelf. Both projects are
investigating how likely changes in calcifier populations at all
trophic levels will impact the food web. Many organisms are expected to
be affected, including coccolithophores (phytoplankton made of calcium
carbonate), pteropods (a form of shelled zooplankton), cold-water
corals, and echinoderm larvae (e.g., sea urchins and sea stars). From
past research on acid rain there is also evidence of acidification's
effect on animal behavior and homing, an area where the NWFSC has also
initiated some preliminary fisheries-related lab studies. Further
investigations could include questions of how changing ocean chemistry
could impact how pollutants are taken up by the ocean, their chemical
form, and their impact on ocean life.
Alaska
NOAA's Alaska Fisheries Science Center (AKFSC) has started research
on the effects of decreased pH on red king crab larval growth and
survival. This project was a pilot study designed to test the ability
to culture crab larvae under experimentally manipulated pH conditions.
Preliminary results showed 15 percent reduction in growth and 67
percent reduction in survival when pH was reduced 0.5 units. Lab work
to determine pH effects on the calcium content of exoskeletons is
ongoing.
Southwest
NOAA's Southwest Fisheries Science Center (SWFSC), as part of the
U.S. Antarctic Marine Living Resource (AMLR) Program, also collected
water and zooplankton samples to investigate effects of ocean
acidification in the Southern Ocean during its 2007 krill biomass
survey. These samples comprise the beginning of NOAA's research to
understand the impact of changing pH in the South Shetland Islands.
Given that in the foreseeable future CO2 levels are likely
to rise, the degree of supersaturation for both aragonite and calcite
(two calcium carbonate (CaCO3) polymorphs) will decline.
This could impact both invertebrate and vertebrate communities.
Aragonite and calcite are the building blocks for skeletal material and
shells of many organisms and lower concentrations of the building
blocks of these minerals in seawater will increase the energy needed by
organisms to form their skeletal and shell structures. This increased
energy need can stress the organisms' physiology. Our data collection
and analysis efforts will provide information necessary for the
development of mitigation options. This work is being completed in
collaboration with scientists from NOAA PMEL and California State
University San Marcos, who will provide the analytical capacity lacked
by the AMLR Program.
National
NOAA Sea Grant serves as a unifying mechanism within NOAA to engage
top universities to assist NOAA in meeting its mission goals and
responsibilities. Sea Grant conducts research, extension, education,
and communication activities, with a goal to achieve a sustainable
environment and to encourage the responsible use of America's coastal,
ocean, and Great Lakes resources. Sea Grant has supported research on
the affects of ocean acidification on coral reefs in Hawaii.
Ocean Acidification Modeling
NOAA's Geophysical Fluid Dynamics Laboratory (GFDL) works
cooperatively throughout the agency to advance its expert assessment of
changes in national and global climate through research, improved
models, and products. GFDL participated in the 1995 Ocean-Carbon Cycle
Model Intercomparison Project (OCMIP), which developed an international
collaboration to improve the predictive capacity of ocean-carbon cycle
models through evaluation and intercomparison. After a 3-year pilot
study with 4 models (OCMIP-1), a second phase of study (OCMIP-2; 1998-
2002) involved 13 international modeling groups and data specialists
taking on a more detailed effort. The models developed by these groups
were used to forecast how ocean chemistry could change under the
`business-as-usual' scenario (as defined by the Intergovernmental Panel
on Climate Change) for future emissions of anthropogenic carbon
dioxide. Under such a scenario, the models predict that the surface
waters of the Southern Ocean will become chemically unfavorable to some
forms of calcium carbonate by the year 2050 (i.e., the pH of the
surface waters will be too low to allow solid calcium carbonate to
form). By 2100, such conditions could extend throughout the entire
Southern Ocean and into the subarctic Pacific Ocean (Orr et al., 2005).
When live pteropods were subjected to chemical conditions predicted by
these models, their shells (calcium carbonate) began to dissolve. The
findings of the study concluded that conditions detrimental to high-
latitude ecosystems could develop within decades.
NOAA can strengthen the existing efforts by improving its
understanding of the climate-ecosystem linkages to better predict
ecosystem (and living marine resource) impacts and adaptations to
climate change. Specifically, NOAA can enhance its monitoring of living
marine resource population demographics, distributions, migrations, and
health.
Additionally, NOAA can translate climate information from global to
regional levels to facilitate management of ecosystem issues at the
regional level.
Question 2. Are there international efforts currently underway or
in development to address the issue of ocean acidification and is the
United States involved in such efforts?
Answer. In addition to the efforts detailed in response to Question
1 (above), over the past year NOAA scientists have been interacting
with their colleagues from Europe and Asia on the development of
international cooperative research efforts on ocean acidification. At
the international level, research on ocean acidification is being
implemented through the Integrated Marine Biogeochemistry and Ecosystem
Research project and Surface Ocean Lower-Atmosphere Study. Senior NOAA
and academic scientists have been invited by their European
counterparts to contribute to the planning and implementation of the
European Project on Ocean Acidification. Similar negotiations are
presently underway with colleagues from Japan and Korea.
Question 3. Coral reefs are not just critical habitat for fish. In
my state of Hawaii, they are also an economic engine supporting both
fishing and tourism. Is ocean acidification or the increase in sea
temperature the more pressing issue for protecting and preserving
Hawaii's coral reefs and other marine resources and why?
Answer. While our present understanding of coral bleaching and
ocean acidification is at an early stage of development, the research
results thus far indicate that increases in sea surface temperature and
changes in ocean chemistry both present considerable risk to the future
sustainability of coral reef habitat and the eco-services they provide
to Hawaii. Both surface temperature and ocean chemistry are related to
changes in atmospheric carbon dioxide concentrations (directly in the
case of ocean acidification) and so the two issues are inextricably
linked. The prevailing expectation of the scientific community is that,
should sea surface temperatures continue to rise, coral bleaching will
continue to occur with greater frequency and intensity. The resilience
of reefs against threats posed by rising temperatures is likely to be
compromised by their declining ability to build reefs as a result of
ocean acidification. While there is much that remains unknown with
regards to how these two processes interact, it is likely the impact of
the two threats together will be greater than the sum of the two
separate impacts.
Question 4. How can we incorporate actions to address these issues
into an overall management strategy for protecting Hawaii's corals and
other marine resources?
Answer. NOAA is committed to an ecosystem approach to resource
management that addresses the many simultaneous pressures affecting
ecosystems. The various effects of climate change on wildlife and
oceans are interrelated. While the strategies outlined in the 2006
publication A Reef Manager's Guide to Coral Bleaching (produced by
NOAA, the Environmental Protection Agency, the Australian Great Barrier
Reef Marine Park Authority, and the International Union for the
Conservation of Nature) were designed to address coral bleaching in
Hawaii and other federally-protected coral reef ecosystems, many of the
strategies in the guide will support reef resilience in the face of
ocean acidification. Additional research is needed to fully
characterize the threat of ocean acidification to coral reef
communities and to identify and devise specific adaptive management
strategies.
Once identified, adaptive strategies that plan for climate change
impacts can be applied to the ocean and coastal environment through a
variety of mechanisms, including incentives and disincentives, policies
and regulations, and public outreach and education. A number of NOAA's
research programs have also begun to consider how climate change, and
specifically ocean acidification scenarios, may impact many regulated
species--particularly bivalve mollusks, crustaceans, and species
dependent on shallow-water coral reefs. Over 50 percent of the value of
U.S. fisheries derives from clams, scallops, and oysters, and various
species of shrimp, crab, and lobster. These shellfish are thought to be
particularly vulnerable to the effects of reduced levels of calcium
carbonate building blocks in the oceans due to increasing acidity.
NOAA's National Marine Fisheries Service has initiated a few pilot
studies to attempt to understand these impacts.
Question 5. Dr. Feely, under a ``business as usual'' scenario of
greenhouse gas emissions, what do you project will be the impacts on
coral reefs and other marine resources?
Answer. The recently released Summary for Policy Makers in the
Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment
Report on Impacts, Vulnerability and Adaptation to Climate Change found
that under a business as usual scenario:
The resilience of many ecosystems is likely to be exceeded
this century by an unprecedented combination of climate change,
associated disturbances (e.g., flooding, drought, ocean
acidification), and other global change drivers (e.g., land use
change, pollution, over-exploitation of resources).
For increases in global average temperature exceeding 1.5-
2.5+ C and in concomitant atmospheric carbon dioxide
concentrations, there are projected to be major changes in
ecosystem structure and function, species' ecological
interactions, and species' geographic ranges, with
predominantly negative consequences for biodiversity, and
ecosystem goods and services, e.g., food supply.
As described in the response to Question 1, NOAA's Geophysical
Fluid Dynamics Laboratory contributed to the Ocean-Carbon Cycle Model
Intercomparison Project. The models that resulted from this project
were used to forecast how ocean chemistry could change under the
`business-as-usual' scenario (as defined by the Intergovernmental Panel
on Climate Change) for future emissions of anthropogenic carbon
dioxide. Under such a scenario, the models predict that the surface
waters of the Southern Ocean will become chemically unfavorable to some
forms of calcium carbonate by the year 2050. By 2100, such conditions
could extend throughout the entire Southern Ocean and into the
subarctic Pacific Ocean.
Recent work indicates that corals in the 21st century will have to
adapt to temperature increases of at least 0.4 degrees Fahrenheit per
decade to survive the increasing frequency and intensity of coral
bleaching that we expect in the next few decades (Donner et al., 2005).
Unfortunately, ongoing studies have not yet shown that corals have the
ability to make physiological or evolutionary changes at that rate.
Limited latitudinal expansion of coral distributions is possible and
may be occurring in one case (Precht and Aronson, 2006). However,
corals in higher latitudes are likely to encounter lower pH waters
(ocean acidification) and their skeletal growth rate may be depressed
(Guinotte et al., 2003; Guinotte et al., 2006).
Question 6. What if we stabilized our greenhouse gas concentrations
at between 445 and 710 parts per million?
Answer. According to the 4th Assessment Report by the
Intergovernmental Panel on Climate Change (IPCC) Working Group II, the
mitigation measure of reducing anthropogenic greenhouse gas emission
can reduce a number of projected climate change impacts. Reducing
greenhouse gas emissions below 445 ppm would specifically act to:
Reduce the level of ocean acidification affecting coral
reefs and other calcifying plankton and shellfish.
Reduce the severity of coral bleaching events.
Note that even reducing greenhouse gas emissions to 445 ppm is
projected only to reduce the severity of coral bleaching events, as
opposed to preventing those events. In addition, because of the inertia
in the climate system, it would take several decades before any
benefits from mitigation efforts materialize. According to the IPCC,
even if complete mitigation were put into place immediately (meaning
even if anthropogenic carbon dioxide emissions were immediately reduced
to zero), because of existing carbon dioxide in the system, we are
committed to a 0.6+ C temperature change over the next 50 years.
______
Response to Written Questions Submitted by Hon. Maria Cantwell to
Richard A. Feely, Ph.D.
Question 1. In your testimony, you discussed the potential impacts
that ocean acidification might have on coldwater species in the Bering
Sea. Along much of the West Coast, we are wrestling with the recovery
of endangered salmon. Salmon are, of course, both commercially and
culturally important, and they're also a critical part of the food web
for the endangered Puget Sound Southern Resident Orca. From your
research, will ocean acidification place these species in further
jeopardy? If so, specifically how might this occur?
Answer. Our understanding of the connections between ocean
acidification and the marine food chain is in a very early stage of
development. Scientists have observed a reduction in the ability of
marine algae and free-floating plants and animals to produce protective
carbonate shells when exposed to decreasing pH (Feely et al., 2004; Orr
et al., 2005). These organisms are important food sources for other
marine species. One type of free-swimming mollusk called a pteropod is
eaten by organisms ranging in size from tiny krill to whales. In
particular, pteropods are a major food source for North Pacific
juvenile salmon, and also serve as food for mackerel, pollock, herring,
and cod. Other marine calcifiers, such as coccolithophores (microscopic
algae), foraminifera (microscopic protozoans), and mollusks (snails,
clams, and mussels) also exhibit a general decline in their ability to
produce their shells with decreasing pH (Kleypas et al., 2006). The
concern among scientists is that as the food sources for the salmon and
whales are reduced in abundance, those populations will also decline.
Question 2. The most rigorous mitigation goal in the recent summary
report by the Intergovernmental Panel on Climate Change is to stabilize
atmospheric greenhouse gas levels between 445 and 710 parts per million
by 2030. But given that the current concentrations of atmospheric
carbon are estimated at 380 parts per million, shouldn't this target be
set at a much lower level if we are to effectively address climate
change? What is the expected temperature increase of this range? What
would be the impacts on our ocean resources if we were to reach these
emissions levels?
Answer. According to the 4th Assessment Report by the
Intergovernmental Panel on Climate Change (IPCC) Working Group II, the
mitigation measure of reducing anthropogenic greenhouse gas emission
can reduce a number of projected climate change impacts. Reducing
greenhouse gas emissions below 445 ppm would specifically act to:
Limit temperature increase to 2.0-2.4+ C
Reduce the future severity of drought in the U.S.
Reduce the level of ocean acidification affecting coral
reefs and other calcifying plankton and shellfish.
Reduce the severity of coral bleaching events (e.g., a 1-3+
C increase in global temperature would result in more bleaching
events with small recovery times, whereas an increase of 2.5-
3.0+ C could result in widespread mortality).
Because of the inertia in the climate system, it would take several
decades before any benefits from mitigation efforts materialize.
According to IPCC, even if complete mitigation were put into place
immediately (meaning if anthropogenic carbon dioxide emissions were
immediately reduced to zero), because of existing carbon dioxide in the
system, we are committed to a 0.6+ C temperature change over the next
50 years. In addition, it is important to note that the IPCC summary
does not explicitly predict the magnitude and timing of consequences
because these depend on the amount and rate of CO2 emissions
and subsequent warming, and, in some cases, on society's ability to
adapt.
Question 3. What are the potential impacts of some of the currently
proposed climate change mitigation strategies on the marine
environment--such as iron stimulated plankton blooms or injection of
CO2 into sea sediments?
Answer. The broad potential impacts of climate change mitigation
strategies are discussed in answer to question 2 (above). In 2005 the
Intergovernmental Panel on Climate Change (IPCC) published a special
report on Carbon Dioxide Capture and Storage (http://www.ipcc.ch/
activity/srccs/index.htm), but the IPCC report does not address
biological approaches for carbon capture and storage in the ocean, such
as iron-stimulated plankton blooms. There have been several small
research projects that have demonstrated that iron fertilization can
cause a phytoplankton bloom in certain regions of the ocean. However,
current scientific evidence indicates that large-scale iron
fertilization will not significantly increase carbon transfer into the
deep ocean or lower atmospheric CO2. Furthermore, there may
be negative impacts of iron fertilization including dissolved oxygen
depletion, altered trace gas emissions that affect climate and air
quality, changes in biodiversity, and decreased productivity in other
oceanic regions.
In 2005 the Intergovernmental Panel on Climate Change (IPCC)
special report on Carbon Dioxide Capture and Storage, one chapter is
devoted to ocean storage of CO2. This report noted that deep
ocean injection is technically possible and would isolate the
CO2 from the atmosphere for several hundreds of years. The
fraction of CO2 retained in the ocean over time generally
tends to be longer with deeper injection, but the cost of placing the
CO2 deeper is also higher. Injection of a few billion metric
tons of CO2 would produce a measurable change in ocean
chemistry in the region surrounding the injection, whereas injection of
hundreds of billions of metric tons of CO2 would eventually
produce measurable changes over the entire ocean volume. Deep-ocean
CO2 injection would introduce anthropogenic CO2
to regions of the deep ocean that have not yet been exposed to elevated
CO2. In particular, the areas around the injection sites
would experience CO2 levels far in excess of anything that
would result from the natural uptake of anthropogenic CO2.
Question 4. Given your understanding of ocean acidification, does
using the ocean to store CO2 make good policy sense, or
would we just be creating additional problems? Are there safe and
effective ways to use the ocean to mitigate the effects of excess
carbon dioxide in the atmosphere?
Answer. The IPCC report mentioned in answer to the question above
(Carbon Dioxide Capture and Storage: http://www.ipcc.ch/activity/srccs/
index.htm) gives several examples of viable carbon storage options,
such as the injection of CO2 into geological reservoirs.
These options appear to have potentially longer storage times and fewer
potential environmental impacts than purposeful ocean carbon storage.
The oceans will continue to take up anthropogenic CO2 for at
least the next few thousand years, thus acting as a natural mitigation
pathway. This natural uptake will have environmental consequences that
we are still trying to understand. At this point, it does not seem to
make sense scientifically to exacerbate this by accelerating the
process and potentially introduce additional unknown oceanographic and
ecological consequences to this valuable resource. Many scientists are
also concerned that such fertilization experiments may have the
unintended consequence of causing harmful algal blooms, sometimes known
as ``red tides.''
______
Response to Written Questions Submitted by Hon. Frank R. Lautenberg to
Richard A. Feely, Ph.D.
Question 1. According to NOAA, about 4,000 species of fish,
including approximately half of all federally-managed fisheries, depend
on coral reefs and related habitats for a portion of their life cycles,
and the National Marine Fisheries Service estimates that the value of
U.S. fisheries from coral reefs exceeds $100 million. Will corals and
plankton be able to survive or adapt to more acidic waters in our
oceans?
Answer. Increasing ocean acidification has been shown to
significantly reduce the ability of reef-building corals to produce
their skeletons, affecting growth of individual corals and making the
reef more vulnerable to erosion (Kleypas et al., 2006). By mid-century,
coral reefs may erode faster than they can be rebuilt potentially
making them less resilient to other environmental stresses (e.g.,
disease, bleaching). This threat to coral reefs could compromise the
long-term viability of these ecosystems, perhaps impacting the
thousands of species and over one billion people that depend on coral
reefs. Decreased calcification rates, as a result of ocean
acidification (decreased pH), may also compromise the fitness or
success of these organisms and could shift the competitive advantage
toward organisms that are not dependent on calcium carbonate
(CaCO3). Carbonate structures are likely to be weaker and
more susceptible to dissolution and erosion as a result of ocean
acidification. In long-term experiments, corals that have been grown
under lower pH conditions for periods longer than 1 year have not shown
any ability to adapt their calcification rates to the low pH levels.
With respect to planktonic calcifiers (free-floating organisms that
rely on calcium carbonate), including the coccolithophores,
foraminifera, and pteropods, each group has been shown to respond
negatively to increases in CO2 levels. However, most studies
of the impacts of ocean acidification have been performed on bloom-
forming coccolithophores, and there are very limited observations of
other planktonic groups. If reduced calcification rates contribute to a
decrease in a calcifying organism's fitness or survivorship, then such
calcareous species may undergo shifts in their latitudinal
distributions and/or vertical depth ranges as the CO2
chemistry of seawater changes. Long-term impacts of elevated
CO2 on reproduction, growth, and survivorship of planktonic
calcifying organisms have not been investigated. Existing studies on
the impacts of ocean acidification on calcareous plankton have been
short-term experiments, ranging from hours to weeks. Chronic exposure
to increased CO2 may have complex effects on the growth and
reproductive success of CaCO3-secreting plankton.
Question 1a. If they cannot, what are the implications for other
marine species and the ocean's food chain?
Answer. The loss of corals and other calcifying species could have
dramatic consequences to marine ecosystems and the human systems that
depend on them. Many reef organisms are dependent on coral reefs for
their livelihood (Kleypas et al., 2006). Organisms that die out locally
during coral bleaching events are likely to be lost. Others will suffer
population drops as erosion of reefs reduces or eliminates the habitats
in which they live. Changes in ocean pH may also affect reproductive
success of commercially important species by reducing demersal egg
adhesion or the fertilization success of eggs broadcast into the ocean.
Some calcifying planktonic species affected by ocean acidification
are key food sources for commercially-targeted fish, such as juvenile
salmon, mackerel, pollock, herring and cod. Therefore, ocean
acidification may reduce the abundance of food for these key species at
the base of the food chain. The concern among scientists is that as the
food sources for the salmon and whales are reduced in abundance, those
populations will also decline.
The economic implications of these types of losses will likely be
similar to those during coral bleaching events. A study discussed in A
Reef Manager's Guide to Coral Bleaching (Cesar et al., 2002) indicates
that the 1998 bleaching in the western Indian Ocean cost U.S. $71.5
million to the Seychelles, U.S. $47.2 million to Kenya, and U.S. $39.9
million to Zanzibar (in Tanzania).
Question 1b. Species have migrated in response to ocean temperature
changes. Will marine organisms migrate to avoid acidification?
Answer. Shallow-water corals are generally limited by water
temperatures and visibility (as clear water is necessary to allow
sunlight to penetrate for photosynthesis). It is possible that corals
will expand poleward as long as proper substrates, temperatures, and
clear water are present. Unfortunately, it takes hundreds to thousands
of years for reefs to develop. Additionally, many corals grow at much
slower speeds (spreading through sexual reproduction and larval
transport) than others coral species. The result is that non-reef
building invading organisms may take over reefs, while slower growing
corals that can be the most important reef-builders are not able to
keep pace with the growth of the non-reef building species. However,
even if corals move poleward, it is the higher latitudes that are most
affected by ocean acidification. While advancing to high latitudes
might stave off thermal stress for a select set of low productivity
corals, these systems would likely be subjected to even slower rates of
reef building due to ocean acidification. Modern reef systems do not
extend to high latitudes in part due to the relatively low pH of these
high latitude waters (Guinotte et al., 2003).
Question 2. There have been ocean acidification events in the past
that have resulted in the disappearance of marine organisms, including
corals. What does the fossil record reveal about the adaptation of
marine organisms to changes in ocean acidification? How long did it
take for corals and other marine organisms to recover from the
acidification events in the past?
Answer. Paleontological studies of coral reef communities before
and after these periods show that many species of corals went extinct
during periods of high atmospheric and oceanic carbon dioxide. For
example, studies indicate that 98 percent of coral species were lost
during the extinction at the end of the Triassic and corals did not
reappear in the fossil record for 8-10 million years (Stanley, 2006).
The few surviving species took millions of years to evolve to fill
the niches left open by the loss of so many corals during these events.
Even then, most reefs were dominated by bivalves (clam-like organisms)
that later went extinct during the next high carbon dioxide period.
That next extinction lasted 17 million years.
Question 3. You indicate in your statement that ``the atmospheric
concentration of carbon dioxide is now higher than experienced on Earth
for at least 800,000 years and is expected to continue to rise . . .
the oceans are absorbing increasing amounts of carbon dioxide . . . and
the chemical changes in seawater resulting from the absorption of
carbon dioxide are lowering seawater pH.'' Have scientists determined a
dangerous level of pH that we need to avoid?
Answer. In order to prevent disruption of the calcification of
marine organisms and the resultant risk of fundamentally altering
marine food webs, the German Council on Global Change (2006)
recommended that the pH of near surface waters should not drop more
than 0.2 units below the pre-industrial average value in any large
ocean region. While that may seem like a small change, it is important
to note that pH units are on a logarithmic scale. This means each whole
pH value below 7 is ten times more acidic than the next higher value.
For example, pH 4 is ten times more acidic than pH 5 and 100 times more
acidic than pH 6. A pH drop of 0.2 units would correspond to an
increase in the hydrogen ion (H+) concentration of around 60
percent compared to pre-industrial values. The decrease in pH so far of
0.11 units since industrialization corresponds to a rise of the
H+ concentration of around 30 percent. The present average
pH value of the ocean surface layer is 8.07.
Question 3a. At the current rate of carbon dioxide emissions, how
long will it take for the oceans to reach a dangerous level of pH?
Answer. At the present rate of carbon dioxide emissions, we will
see a pH drop of 0.2 units from the pre-industrial values by about 2050
(500 ppm CO2 in the atmosphere). According to simulations by
Caldeira and Wickett (2005), a stabilization of the atmospheric
CO2 concentration of 540 ppm by the year 2100 would lead to
a global average surface ocean pH decrease of 0.23 compared to the pre-
industrial level. Thus, an atmospheric CO2 concentration of
540 ppm would already exceed the acidification limit of 0.2 units.
Question 3b. Have scientists determined at what level of carbon
dioxide concentrations we need to maintain in order to avoid this
dangerous level of pH?
Answer. As stated in Question 3 above, the German Council on Global
Change (2006) recommended that the pH of near surface waters should not
drop more than 0.2 units (<500 ppm CO2 in the atmosphere)
below the pre-industrial average value in any large ocean region.
The largest threat to marine organisms due to ocean acidification
is related to the solubility of calcium carbonate, which affects the
presence of the carbonate minerals calcite and aragonite. Calcite and
aragonite are needed for the construction of shells and skeletal
structures. Calcifying marine organisms are important components of
marine ecosystems, so their endangerment would have a large impact on
economically and socially important marine resources. The German
Council on Global Change (2006) states ``If the concentration of
carbonate ion falls below the critical value of 66 mmol per kilogram,
then the seawater is no longer saturated with respect to aragonite, and
marine organisms can no longer build their aragonite shells'' (Schubert
et al., 2006). The danger of undersaturation for aragonite is
especially present in the high northern and southern latitudes, and in
strong upwelling regions.
Question 4. In light of the latest findings published last month in
the journal Science in which the biological consumption and
remineralization of carbon in the ``twilight zone''--a zone in the
ocean where some sunlight reaches but not enough for photosynthesis to
occur at ocean depths between about 660-3,300 feet--actually reduces
the efficiency of sequestration (Buesseler, et al., Science 316, 567,
2007). What does this mean for the future of carbon sequestration in
our ocean if carbon is recycled back into the surface ocean and
atmosphere faster than originally thought?
Answer. The significance of the Buesseler et al. (2007) article is
that much of the carbon that is sequestered in marine organic matter in
the surface euphotic zone is remineralized in the twilight zone and
returned to the atmosphere at some later date due to upwelling. The
farther down in the ocean this organic carbon remineralization occurs,
the longer it takes for the CO2 to be returned back to the
atmosphere. Consequently, the approach of using iron-fertilization as a
mechanism for sequestering organic carbon in the oceans may be less
inefficient than previously thought because of this remineralization
mechanism.
Question 4a. Do scientists know how much carbon sequestered to the
deep ocean is being overestimated?
Answer. At the present, this is an area of active scientific
research because the present carbon reminearlization estimates have
very large uncertainties. In the study discussed above (Buesseler et
al.) point out that the uncertainty in the estimates of carbon
remineralization is as high as 3 Pg C year-1, which is more
than our best estimate of the anthropogenic carbon uptake at the
surface!
Question 4b. How has this changed what scientists think about how
long carbon dioxide will be naturally sequestered and how long it will
take material to resurface from the twilight zone?
Answer. The Buesseler et al. (Science 316, 567, 2007) article
points to the need for more research on the nature and rates of organic
matter remineralization processes in the twilight zone. We need to know
if ocean acidification will enhance the process of remineralization in
shallow waters by causing calcium carbonate
(CaCO3) shells, and their associated organic
carbon (ballast carbon), to dissolve higher up in the water column.
This is potentially one of the most important positive ocean feedback
mechanisms for enhancing the return of CO2 back to the
atmosphere.
Question 5. It is essential to start a global research and
monitoring program for ocean acidification. We should be utilizing the
observing systems already in place including the undersea research
program. What are your recommendations for utilizing the current
infrastructure of ocean observing systems and satellites to monitor
ocean acidification?
Answer. As technology develops, our current ocean observation
infrastructure may be enhanced by including additional specific sensors
to monitor ocean acidification. For example, NOAA scientists and
partners recently launched the first operational buoy with a new sensor
to monitor ocean acidification in the Gulf of Alaska. This is the first
system specifically designed to monitor ocean acidification, and is a
new tool for researchers to examine how ocean circulation and
ecosystems interact to determine how much carbon dioxide the North
Pacific Ocean absorbs each year. The addition of similar carbon system
sensors onto current observation platforms, such as the OceanSites
moored arrays (funded by NOAA and the National Science Foundation and
Coral Reef Metabolic Monitoring Network) could provide an excellent
foundation for a global monitoring program to monitor ocean
acidification in the Atlantic and Pacific and to validate models of
future changes.
Question 5a. What information can be gained from monitoring natural
variations over a long time period of time and in several different
oceanic regions?
Answer. These data sets provide information on long-term natural
and anthropogenic variability of the carbon system in the oceans. They
are critical for understanding the future impacts on biological systems
via ocean acidification.
Question 6. This year I requested funding through the
Appropriations Subcommittee on Commerce, Justice, Science to fund the
National Research Council report on ocean acidification mandated by
Magnuson-Stevens Fishery Conservation and Management Reauthorization
Act. Has NOAA yet identified the compelling research needs for this
study?
Answer. Yes, NOAA has identified key issues associated with ocean
acidification and fisheries, and how the National Academy of Science's
Ocean Studies Board can help prioritize future research and monitoring
to address this significant issue. NOAA and other agencies must
collaborate to design appropriate field and laboratory studies that
will allow more precise forecasts of the impacts of ocean acidification
on fisheries and the ecosystems that support them.
Question 6a. If so, what are the research needs for this report?
Answer. NOAA believes that the National Academy can provide an
important bridge between the academic community and Federal agencies in
designing and implementing appropriate long-term monitoring studies and
experiments to determine how fisheries species and ecosystems may
respond to acidifying oceans. The National Academy study, to be
conducted through its Ocean Studies Board (OSB), will be used to help
design long-term studies to monitor pH changes in vulnerable marine
ecosystems of the United States, and as a method to collaborate
internationally. The OSB will determine the methods, frequency and
placement of monitoring sensors and oceanographic sensing to track
ocean acidification over time, and in relation to changes in
atmospheric CO2.
Currently about 51 percent of the value of United States fisheries
landings is made up of bivalve mollusks and crustaceans. As these
species contain high levels of calcium carbonate as shell material,
they are thought to be particularly vulnerable to ocean acidification.
Ocean plankton, the base of shallow-water marine food chains, include
species that also incorporate calcium carbonate into their shells and
are thus likely to be influenced by acidification. Other species,
contributing about 5 percent of the value of U.S. fisheries, occur in
shallow water tropical coral ecosystems that are highly sensitive to pH
variations and temperature changes. Finally, deep-sea coral ecosystems
are also likely to be impacted by ocean acidification and these species
are now regulated under the newly re-authorized Magnuson-Stevens
Fishery Conservation and Management Act. The National Academy study
will determine which of these biological communities are most at risk,
and will design appropriate field and laboratory studies of the
physiological responses of these organisms to ocean acidification.
In addition to the National Academy study, which will focus on
monitoring and research strategies and priorities for the U.S., NOAA
will also coordinate international ocean acidification science with the
International Council for the Exploration of the Sea and the Pacific
Marine Science Organization. These two groups, in particular,
coordinate marine science among countries in the North Atlantic and
North Pacific, and can assure that U.S. research priorities integrate
with research conducted by other nations.
Question 7. About one-third of all man-made carbon dioxide
emissions are absorbed into the ocean. However, at a certain point the
oceans may no longer be able to absorb carbon dioxide at the same rate.
If this happens, warming of the atmosphere will increase even more
rapidly. Are we close to seeing the rate that the oceans absorb carbon
dioxide slow down to a point that our global temperatures increase even
faster?
Answer. The uptake of anthropogenic CO2 is controlled by
the carbon chemistry at the surface and the rate at which surface
waters, laden with anthropogenic CO2, are moved into the
ocean interior and replaced with deeper waters that have not been
exposed to higher atmospheric CO2 concentrations. The rate
at which the surface waters can take up CO2 depends on the
difference in CO2 concentration in the air and sea surface,
and the amount of CO2 that is converted to other ionic
species (such as bicarbonate (HCO3), carbonate
(CO32-), and carbonic acid
(H2CO3-) in seawater. As
CO2 concentrations in the ocean increase, the percentage of
CO2 that is converted to these other ionic species
decreases, and the water becomes less efficient at taking up
CO2. This is already happening--the surface water of the
oceans has already become less efficient at taking up CO2.
However, even with the ocean's decreased efficiency with regard to
taking up CO2, the exponential increase in atmospheric
CO2 concentration up to this point has made it such that
today's oceans take up more CO2 each year than they have in
the past. That being said, there are many things that can change this
situation because the rate at which the ocean absorbs CO2 is
a balance between a number of processes. For example, if the rate at
which CO2 is moved from the surface ocean into the interior
ocean slows because of changes in thermohaline circulation, then the
rate of CO2 absorption will also decrease. If the rate at
which CO2 is rising into the atmosphere slows, then the
ocean uptake rate will also decrease. Predicting when and how these
processes, and others not listed here, will change is difficult.
According to Chapter 5 of the 4th Assessment Report by the
International Panel on Climate Change Working Group I, the fraction of
the net CO2 emissions taken up by the ocean (the uptake
fraction) was 37 percent 7 percent during the period from
1980 to 2005, compared to 42 percent 7 percent during the
1750 to 1994 period. The errors in this estimate are still too large to
determine if these rates are different.
Question 7a. How does temperature affect the rate at which ocean
acidification occurs?
Answer. CO2 is less soluble in warm water, so as the
oceans warm they will become less efficient at taking up CO2
from the atmosphere. In addition, as you warm a body of water but keep
the total amount of dissolved carbon the same or greater, then the
proportion of carbonic acid (H2CO3, the acidic
form of carbon dioxide) in the water will increase, and the pH of the
warmer water will therefore be lower. Thus, rising ocean temperatures
will tend to accelerate ocean acidification.
However, temperature's impact on the rate at which ocean
acidification occurs is small relative to the impact of rising
atmospheric CO2 levels. As CO2 concentration
continues to increase in the atmosphere, the ocean will continue to
take up larger quantities of CO2, thereby exacerbating ocean
acidification.
Question 7b. The Arctic Ocean is becoming warmer and fresher which
may slow down thermohaline circulation. What are the implications of
these changes on ocean acidification?
Answer. The Arctic Ocean is one of the oceanic regions that will
experience major changes in carbonate saturation due to ocean
acidification over the next 40-50 years. This is primarily due to the
extremely low temperatures of the surface waters and lowered
alkalinities due to the ice melting.
Question 7c. How does the increase in atmospheric carbon dioxide
and subsequent warming affect atmospheric and oceanic circulation? Will
the increase in atmospheric and ocean temperatures result in more
frequent El Nino's and intense hurricane seasons?
Answer. The oceans and the atmosphere constitute intertwined
components of Earth's climate system. Evaporation from the ocean
transfers huge amounts of water vapor to the atmosphere, where it
travels aloft until it cools, condenses, and eventually precipitates in
the form of rain or snow. Changes in ocean circulation or water
properties can disrupt this hydrological cycle on a global scale,
causing flooding and long-term droughts in various regions.
Higher temperatures caused by increases in atmospheric carbon
dioxide could add fresh water to the northern North Atlantic by
increasing precipitation and by melting nearby sea ice, mountain
glaciers, and the Greenland ice sheet. This influx of fresher and
warmer water could reduce the sea surface salinity and density, leading
to a slow down of the global hydrological cycle (thermohaline
circulation).
According to all models used in the 4th Assessment Report by the
Intergovernmental Panel on Climate Change Working Group I, the strength
of the atmospheric overturning circulation decreases as the climate
warms (Held and Soden, 2006; Vecchi and Soden, 2006), in a manner
consistent with theoretical arguments (Betts and Ridgeway, 1989; Betts,
1998; Knutson and Manabe, 1995; Held and Sodden, 2006). The models
project that this weakening should occur preferentially to the east-
west overturning of air near the Equator, known as the Walker
circulation. Such a weakening of the Walker circulation, in turn, would
lead to a reduction in near-surface wind-driven currents in the near-
equatorial oceans (Vecchi and Soden, 2007). Long-term records of
atmospheric sea-level pressure indicate that weakening of the Walker
circulation may already be underway, and this weakening is partially
attributable to increases in greenhouse gases (Vecchi et al., 2006;
Zhang and Song, 2006). However, long-term changes of oceanic conditions
are mixed, with some studies showing changes inconsistent with a
slowing circulation (Cane et al., 1997; Hansen et al., 2006) and other
studies showing changes more consistent with the slowing circulation
(Cobb et al., 2001, 2003).
The El Nino-Southern Oscillation (ENSO) system is a naturally
occurring climate phenomenon that leads to major fluctuations in global
climate patterns at approximately 3-7 year intervals. There is
scientific debate over the influence that rising globally-averaged
temperatures has had and will have on the frequency and intensity of
ENSO fluctuations. What is certain is that natural fluctuations in
temperature lead to warmer and cooler years than normal. If the average
temperature is rising, as it has in the 20th century and is expected to
in the 21st century (Guinotte et al., 2003), the warm temperatures
during natural oscillations periods will be even hotter than those of
the past. How the mechanisms responsible for controlling the timing and
intensity of El Nino's will likely change in a warming climate is still
not clear (van Oldenborgh et al., 2005). Therefore, it is difficult to
say whether warming will result in more frequent El Nino's. We do know,
however, that El Nino's have a dramatic impact on the ability of the
oceans to take up CO2, so if the frequency of ENSO events
does change then it will definitely impact ocean acidification.
It is likely that some increase in tropical cyclone peak wind-speed
and rainfall will occur if the climate continues to warm (IPCC, 2007).
However, there is no firm conclusion on whether there is currently a
global warming signal in the tropical cyclone climate record to date.
Models also project that storm tracks should move poleward in a warming
world (Yin, 2005), and that the northern edge of the sinking branch of
the equator-subtropics overturning of air--known as the Hadley
circulation--should move polewards, with an associated poleward
movement of dry regions (Lu et al., 2006).
Question 7d. Which ocean regions will be first to experience large
changes in carbonate chemistry? How long before large changes occur?
Answer. According to the modeling studies of Orr et al., (2005,
2006), the Arctic and Southern Oceans will become undersaturated with
respect to aragonite in the second half of this century. During this
period, the Southern Ocean's aragonite saturation horizon shoals from
its present average depth of 730m all the way to the surface. Similar
large migrations of the aragonite saturation horizon are projected for
the North Atlantic. In the North Pacific, portions of the subarctic
Pacific will undergo undersaturation (with respect to aragonite) by the
end of the century. In the Orr et al. (2005) modeling study, the
concentration of carbonate ions that corals use to build their
skeletons (the reef) will become inadequate to support reefs around the
middle of the century.
Question 8. How will lower calcification rates, due to an increase
in ocean acidification, higher ocean temperatures, and changes in
nutrients affect ocean carbon chemistry and carbon export rates?
Answer. As indicated in the answer to Question 4b above, the
Buesseler et al. (2007) article points to the need for more research on
the nature and rates of organic matter remineralization and carbon
export processes in the upper water column. We do not know if ocean
acidification will enhance the process of remineralization in shallow
waters by causing calcium carbonate shells, and their associated
organic carbon (ballast carbon), to dissolve higher up in the water
column. This is potentially an important positive ocean feedback
mechanism for enhancing the return of CO2 back to the
atmosphere.
Question 9. What are the expected changes to the biological pump--
the process which transports carbon throughout the ocean--due to the
increase in carbon dioxide and what will be the consequences of these
changes?
Answer. Calcium carbonate particles play a significant role in the
transport of organic matter to the deep ocean by acting as a ballast
mineral particle, absorbing organic matter at shallow depths and
carrying it downward as the particles settle to deeper depths and
dissolve.
Calcium carbonate dissolution at increasingly shallower depths in
the oceans could possibly decrease the depth of remineralization of
organic matter, causing a reduction in the ocean uptake of
CO2. This process needs to be quantitatively assessed for
changing pH conditions in the oceans.
Question 10. Fossil-fuel use is also increasing the amounts of
nitric and sulfuric acid deposition in the oceans. How will these
elements alter surface seawater alkalinity and pH?
Answer. Anthropogenic nitrogen and sulfur deposition to the ocean
surface alter surface seawater chemistry, leading to acidification and
reduced total alkalinity. The acidification effects, though not as
large globally as those of anthropogenic CO2 uptake, could
be significant in coastal ocean regions.
Question 10a. Will the impacts of these elements differ in coastal
waters versus open ocean and how may they affect marine ecosystems?
Answer. According to a recent paper by Doney et al. (in press,
Proceedings of the National Academy of Science, 2007), the deposition
of anthropogenic nitrogen and sulfur has a relatively small effect on
changes in open-ocean surface water chemistry, relative to the effect
of CO2 increases due to the oceanic uptake of anthropogenic
CO2. However, the impacts of nitrogen and sulfur are more
substantial in coastal waters, where the ecosystem responses to ocean
acidification could have severe implications for coastal inhabitants.
Question 11. During the hearing a question was raised regarding the
global average increase in ocean temperature of 0.04+ C. It is well
known that the largest increases in ocean temperature are in the
surface waters and this plays a large role in the Earth's heat budget.
Can you please explain how significant the warming has been in the
surface waters and what the implications have been for increased sea
surface temperature as it relates to hurricane intensity, El Nino,
drought, and other extreme weather events?
Answer. Based on historic and paleoclimatic records, the global
mean land and ocean surface temperature has increased by
0.80.2+ C (1.40.3+ F) since the last half of
the nineteenth century, and global mean surface temperatures increased
at a rate of about 0.2+ C/decade over the last few decades. Present
temperatures are the warmest on record going back through at least the
last 1,000 years, and we will likely soon be experiencing temperatures
warmer than at any time in the last million years (Hansen et al.,
2006). Subsurface ocean temperatures down to 3,000 m (10,000 feet)
depth are also on the rise. More than 80 percent of the added heat
resides in the ocean. The impacts of the increased heat content are
described below.
Hurricane Intensity: It is likely that some increase in
tropical cyclone peak wind-speed and rainfall will occur if the
climate continues to warm; however, there is no firm conclusion
on whether there is currently a global warming signal in the
tropical cyclone climate record to date.
El Nino: The El Nino-Southern Oscillation (ENSO) system is a
naturally occurring climate phenomenon that leads to major
fluctuations in global climate patterns at approximately 3-7
year intervals. There is scientific debate over the influence
that rising globally-averaged temperatures has had and will
have on the frequency and intensity of ENSO fluctuations. What
is certain is that natural fluctuations in temperature lead to
warmer and cooler years than normal. If the average temperature
is rising, as it has in the 20th century and is expected to in
the 21st century, the warm temperatures during natural
oscillations periods will be even hotter than those of the
past.
Drought: Droughts have increased, consistent with
acceleration in the water cycle and greater evaporation and
transport of water vapor at the scale of continents. Observed
changes in sea surface temperatures, circulation patterns and
decreased snowpack and snow cover are also linked to drought.
Question 11a. Can you highlight different regions that have
experienced large increases in surface water temperature and how much
the surface waters have warmed?
Answer. According to the 4th Assessment Report by the
Intergovernmental Panel on Climate Change (IPCC) Working Group I, the
oceans are warming. Recent warming is strongly evident at all latitudes
in sea surface temperatures (SST) over each of the oceans: there are
inter-hemispheric differences in warming in the Atlantic; the Pacific
is punctuated by El Nino events (discussed in detail in answer to
question above) and Pacific decadal variability that is more symmetric
around the equator; while the Indian ocean exhibits steadier warming
throughout. These characteristics lead to important differences in
regional rates of surface ocean warming, and understanding of the
variability and trends in different oceans is still developing. A full
discussion of observations and oceanic climate change and sea level is
included in Chapters 3 and 5 of the IPCC Working Group I report.
Estimating regional SST increases is more difficult than estimating
global ocean temperature increases, due to uncertainties in how missing
data points are dealt with and in correcting for systematic errors in
measurements. These uncertainties are all amplified at the smaller
scale (e.g., regional vs. global) and the further we go back in time.
Given the uncertainties indicated above, following is a list of
linear trends in SST in the tropics, computed over the period 1880-
2006, in units of +C per 100 years--to get the total rise of the linear
trend, multiply by 1.27:
Averaged across the tropics, sea surface temperatures have
increased at a rate of 0.35-0.45+ C per 100 years since the
1880s.
The largest tropical warming in the 20th century has
occurred in the northern Indian Ocean (0.46-0.73+ C per 100
years) and the southern tropical Atlantic (0.56-0.77+ C per 100
years) since 1880.
For the northern tropical Atlantic, the range is between
0.24-0.52+ C per 100 years since 1880.
In the tropics, the greatest uncertainty in temperature
trend is in the eastern equatorial Pacific, where sparse data
and strong natural year-to-year fluctuations associated with El
Nino/La Nina make estimating the long-term trend more
problematic than in other regions, the observationally-based
estimates range from 0.12-0.5+ C per 100 year since 1880.
These trends are based on the Kaplan et al., (1998), Rayner et al.,
(2003), and Smith and Reynolds (2004) SST datasets, and are computed
over the period 1880-2006. The exact regions used to calculate these
trends:
Tropics: Global, 30+ S-30+ N.
Northern Indian Ocean: 50+ E-100+ E, 0+ N-20+ N.
South Atlantic: 40+ W-10+ E, 20+ S-0+ N.
North Atlantic: 80+ W-30+ W, 5+ N-20+ N.
Eastern Equatorial Pacific: 150+ W-90+ W, 5+ S-5+ N.
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______
Response to Written Questions Submitted by Hon. Daniel K. Inouye to
Dr. Lara J. Hansen
Question 1. Coral reefs are not just critical habitat for fish. In
my state of Hawaii, they are also an economic engine supporting both
fishing and tourism. Is ocean acidification or the increase in sea
temperature the more pressing issue for protecting and preserving
Hawaii's coral reefs and other marine resources and why?
Answer. You can not prioritize one of these issues over the other.
They share the same root cause and will both dramatically affect our
Nation's coral reefs. Increasing atmospheric CO2 is
increasing global temperatures, including the ocean's temperatures.
This same CO2 is being absorbed by our oceans and lowering
their pH. They are inextricably linked; prevent one and you prevent
both, and if you fail to prevent either it will result in an increase
in global as well as ocean temperatures. Unfortunately, we are already
seeing the manifestation of both. It is possible that ocean
acidification is the more ominous as we do not know all of the effects
it will have, owing to our long believe that the ocean's vast buffering
capacity prevents such things in our timeframe. It exacerbates the
ongoing adverse effects we have been seeing due to increasing water
temperature for the past several decades. We must do everything we can
to limit both.
Question 2. How can we incorporate actions to address these issues
into an overall management strategy for protecting Hawaii's corals and
other marine resources?
Answer. There are four general steps that WWF feels are crucial to
improving management in the face of climate change. First, you must
assess where your resources are and ensure that those which are
naturally more resilient are protected. Where possible you manage along
climatological gradients so that these ecosystems can respond
accordingly. Second, you must limit all of the non-climate stresses to
levels where climate change's added stress does not exacerbate them, or
vice versa. This includes further reducing acceptable levels of habitat
loss and fragmentation, pollutants, invasive species, disease/pests,
and over- or destructive harvest. Third, we need to start implementing
these approaches as soon as possible, in a do-no-harm manner, start
monitoring them, adjust as necessary and share lessons widely. Fourth,
we must reduce the rate and extent of climate change. This means to
rapidly reduce greenhouse gas emissions.
Question 3. Dr. Hansen, could you tell me what adaptation and
mitigation steps you think the United States needs to take to address
the threats that climate change and ocean acidification pose to our
ocean resources?
Answer. First and foremost we need to get serious about reducing
greenhouse gas emissions. Nothing we have done to date gets close to
what we must do to save our national and global economy, natural
resources, biodiversity and well-being. We need to do this as quickly
as possible. This means taking action to improve conservation of energy
(fuel economy, reduced use of long-distance transmission of
electricity, real standards on appliances), switch to renewable
energies that produce no greenhouse gases and finally, decommission
those sources of power generation that do.
Second, we need to recognize that we are already committed to a
certain level of climate change, likely about 2 degrees Celsius (I
believe that even this is too much). We must also recognize that this
will have serious impacts on our oceans, our citizens, our forests, our
freshwater systems, our highway systems, our wastewater treatment
facilities, and our agricultural system. We need to rethink every piece
of legislation, and assess whether or not it is prepared for climate
change. Are we making bad investments because they are vulnerable to
the effects of climate change? We need to think proactively now because
the climate is changing rapidly. There is a book about the Arctic
climate experience called ``The World is Faster Now''. It is and we
must be prepared.
______
Response to Written Questions Submitted by Hon. Maria Cantwell to
Dr. Lara J. Hansen
Question 1. The most rigorous mitigation goal in the recent summary
report by the Intergovernmental Panel on Climate Change is to stabilize
atmospheric greenhouse gas levels between 445 and 710 parts per million
by 2030. But given that the current concentrations of atmospheric
carbon are estimated at 379 parts per million, shouldn't this target be
set at a much lower level if we are to effectively address climate
change? What is the expected temperature increase of this range?
Answer. 2.0 to 4.0+ C
Question 1a. What would be the impacts on our ocean resources if we
were to reach these emissions levels?
Answer. Allowing emissions levels to reach the upper end of this
range is still unfathomable. For the past 650,000 years we have stayed
between about 180 and 300 ppm. To now be at 384 ppm and say we are
headed to 710 should be seen by this planet's inhabitants as
unacceptable. That amount of warming would mean unprecedented coral
bleaching, loss of many, if not most coral species, altered marine food
webs as species shift their ranges or simply disappear (imagine if you
will what the loss of krill, the base of the marine food web, would
mean for life on Earth?), changes in the dominant phytoplankton species
(these are what produce most of our oxygen), loss of most of the
world's terrestrial ice causing massive sea level rise, altered ocean
currents and even more heating as the planet becomes less reflective.
All of these changes will cause unprecedented responses in human
communities, such as movement of climate refuges, famine, and disease.
In all honesty, this level of warming is not something that ecologists
like to ponder; it may be one of the most cataclysmic scenarios that I
can ponder.
Question 1b. Do you think that policymakers should specifically
take ocean impacts into account when setting emissions reductions
targets?
Answer. Absolutely. The oceans provide myriad services that we take
for granted but they sustain life on this planet. We must also
recognize that the more CO2 we put in the atmosphere, the
greater the ocean acidification commitment, which is something that we
do not fully understand the consequences of.
Question 1c. Do current emissions reduction targets sufficiently
consider ocean impacts?
Answer. Most certainly not.
Question 1d. How do you think policymakers should incorporate ocean
impact concerns when setting emissions reduction targets?
Answer. Yes, please see above.
Question 2. Dr. Hansen, I understand that you were part of a team
that produced NOAA's publication titled ``A Reef Managers Guide To
Coral Bleaching''. This handbook acknowledges that climate change is
outside of the immediate control of most managers, and recommends that
the best management strategy is often to reduce stressors that are
within local control--such as reducing pollution or overfishing. What
can managers facing ocean acidification learn from this approach? What
are some concrete steps in the short-term and long-term that can be
taken to adapt to these impacts?
Answer. Perhaps the most daunting challenge is to develop
adaptation strategies in response to ocean acidification. It ranks up
there with how to protect sea ice dependent creatures in a world
without ice. The only short-term strategy that my team has developed is
working to limit all of the other stresses so that systems can try to
keep up with this change without it being exacerbated by other
challenges. Unfortunately one of the key stresses that can aggravate
this is warming waters. The same actions that cause acidification cause
warming.
Question 2a. Aside from reducing emissions, what other steps should
policymakers be taking to address the impact of climate change and
ocean acidification on the oceans?
Answer. We should start doing everything we can to make ocean
systems more robust, by reducing all of the other insults we have sent
their way. But really, the only solution, the only lifeline for the
oceans, is for us to stop dumping CO2 in them, which is
exactly what we do when we dump it into the atmosphere.
Question 3. What are the potential impacts of some of the currently
proposed climate change mitigation strategies on the marine
environment--such as iron stimulated plankton blooms or injection of
CO2 into sea sediments?
Answer. Storing CO2 in the world's oceans, either
through direct injection or stimulating phytoplankton assimilation is
risky business. You are trading one environmental disaster for another.
There may be some merit to storing carbon in old oil and gas deposits
since they are presumably not environmentally sensitive locations, but
this is not true of the ocean. In the case of injection, you are
damaging the deep ocean communities which are very sensitive to such
changes in pH and gas composition as they are extremely stable systems
(very little variability in any physical parameters). You are also
acidifying the oceans from the bottom up, rather than the top down. In
the case of ocean ``fertilization'' you are increasing ocean
productivity, which can have negative consequences as well as the
desired. You will change the species composition of the phytoplankton
community, selecting for species that are iron limited. These
phytoplankton, in their current composition, provide many ecosystem
services. Will the new set do so as well? We don't know.
______
Response to Written Questions Submitted by Hon. Daniel K. Inouye to
James D. Watkins
Question 1. Admiral Watkins, what are the most important steps that
the United States should take to address the threats we are learning
about today, in terms of research and monitoring, outreach and
education, and adaptation and mitigation measures? Can you identify
some specific actions that Congress should take to strengthen Federal
efforts in the area of ocean impacts of climate change?
Answer. This reply is to questions 1 and 3 from Chairman Inouye.
Earlier this summer JOCI consulted with leading experts in ocean and
climate change science and policy regarding the development of
recommendation for incorporating oceans as part of climate change
legislation under consideration by Congress. The Initiative suggests
that Congress address the link between oceans and climate change by
addressing needs in two key areas: governance reform and science.
Clearly, additional funding will be necessary to make sustained
progress in both areas. A more detailed discussion of our
recommendations is included in the attached paper, which was sent to
leaders in the House and Senate, as well as the Administration. I
request that the entire text of the paper be included as part of my
reply to the Committee's follow-up questions.
Below is brief summary of the key recommendations from the paper.
Governance Reform
Climate change involves complex and dynamic interactions of the
atmosphere, ocean, land, their related ecosystems, and human
activities. The complexity and breadth of issues associated with
efforts to understand, mitigate, and adapt to climate change, the scale
of its impacts from the local to the global level, and the need to
understand the relationship between natural variability and climate
change, make it essential that the Nation have a coherent and
comprehensive strategy to address this new challenge. This will require
the establishment of a Climate Change Response Office to guide the
development and implementation of a National Climate Change Response
Strategy.
Ocean science and management must be recognized as key elements of
such a national response strategy. Actions that would help ensure this
occur include codifying the White House Committee on Ocean Policy and
charging it with supporting a broader National Climate Change Response
Strategy. Another beneficial step would be to codify and strengthen the
National Oceanic and Atmospheric Administration (NOAA), which is the
key Federal agency providing climate-related services and ocean
management information. Finally, Congress should require a biennial
integrated assessment of the Nation's progress toward mitigating and
adapting to climate change impacts. An integrated assessment evaluating
the collective effort of Federal programs and activities will provide a
baseline from which to measure progress and will help ensure the Nation
is maximizing the use of available data and information to improve the
caliber of forecasts and to evaluate the effectiveness of management
actions.
1. Charge the National Academy with recommending a process and
strategy to respond to climate change, including consideration
of the organization and functions of a National Climate Change
Response Office responsible for guiding Federal programmatic
and budgetary climate change activities.
2. Codify and strengthen the White House Committee on Ocean
Policy, and give it a key role in supporting the activities of
the Climate Change Response Office.
3. Codify and strengthen the National Oceanic and Atmospheric
Administration (NOAA), realigning the agency's organizational
structure to enhance and focus its capacity to provide climate-
related services and improve ocean and coastal management.
4. Require a biennial integrated assessment of the Nation's
progress toward meeting its objectives to mitigate and adapt to
impacts associated with climate change and variability.
5. Require the submission of an integrated budget to
consolidate and highlight priorities established by the
National Climate Change Response Office that would accompany
the President's annual budget request.
Science Requirements
Credible and timely scientific information will be essential as the
Nation begins the process of responding to the challenges associated
with climate change. A much more comprehensive and robust science
enterprise that incorporates a better understanding of the ocean's role
in climate change is required to forecast more accurately the magnitude
and intensity of this change at multiple scales, as well as to evaluate
options for mitigation and adaptation. Unfortunately, the existing
ocean and coastal science enterprise supporting climate change
research, observations, data management, and socioeconomic analysis is
limited.
The status of infrastructure supporting ocean science, such as
ship, satellites, buoys, cabled observatories, planes, and other
monitoring hardware, is bleak. Additionally, support for shore-side lab
work, where data for the observing systems is analyzed, quality-
controlled, synthesized, and integrated, has eroded. Further underlying
these weaknesses is a lack of capability to transmit large amounts of
ocean data in real time and a disjointed data management system that
prevents scientists from fully utilizing the data that are being
collected now.
Congress can begin to remedy this situation by calling on the
administration to prioritize and request full funding to implement its
Ocean Research Priorities Plan and Implementation Strategy (ORPPIS).
ORPPIS provides a solid blueprint to guide research on the ocean's role
in climate. It is the first comprehensive research strategy developed
by the Administration with input from the ocean community and should be
used by Congress to guide its ocean science funding priorities.
Congress should also authorize and fund the implementation of an
Integrated Ocean Observing System (IOOS), with the system being driven
by a cooperative interagency process that incorporates expertise from
outside the Federal system. Sustained research and operational
monitoring and analyses programs supported by enhanced data collection,
management, and synthesis capabilities are the foundation of an
observation system that can refine climate change models and reduce the
level of uncertainty associated with their projections.
Finally, Congress should support research and science programs
focused on analyzing the potential impact various greenhouse gas
mitigation strategies may have on ocean and coastal processes and
ecosystem health. Recommendations for carbon sequestration in the
oceans will require particularly careful review, given our growing
concern about the sensitivity of marine ecosystems to changes in the
biogeochemistry of ocean waters as a result of increased absorption of
carbon dioxide, in particular ocean acidification.
1. Request prioritization of and provide funding to implement
the Administration's Ocean Research Priorities Plan and
Implementation Strategy, with a focus on developing a science
enterprise that is responsive to societal and environmental
concerns.
2. Enact legislation authorizing the implementation of an
Integrated Ocean Observing System, incorporating both coastal
and global components.
3. Fund major ocean observation research and monitoring
infrastructure systems and supporting science and data
management programs, such as an Integrated Ocean Observing
System, the Ocean Observatories Initiative, research vessels,
and remote sensing programs.
4. Enhance funding support for transitioning ocean and
atmospheric data collection and synthesis programs from
research to operational status, with ongoing engagement of the
ocean science community in the operation, evaluation, and
evolution of the programs.
5. Support research to evaluate the impact of greenhouse gas
mitigation policies on coastal and ocean processes and
ecosystem health (e.g., oceanic carbon sequestration, biofuel
production).
Question 2. Do you believe that the current Federal budget to
address the ocean impacts of climate change is sufficient?
Answer. Clearly, the answer is no, as I responded when Senator
Stevens asked a similar questions during the hearing. The short- and
long-term implications of climate change are significant in
relationship to the impact on the environmental health of marine
ecosystems and the economic vitality of coastal communities. In the
recent Joint Initiative report to Congress, ``From Sea to Shining
Sea,'' we identify $750 million in high priority funding needs to
support the recommendations of the two Commissions. Much of the funding
identified in this report would directly contribute to improving our
understanding of the oceans role in climate processes, as well as
strengthen coastal community's capacity to adapt to the changes
accompanying these shifts. For example, we support enhancing ocean
governance and coastal management, such as improving interagency
collaboration, expanding regional coordination, and strengthening
programs that focus on system-wide watershed activities, such as the
Coastal Zone Management Program and USDA and U.S. Army Corps of
Engineer programs.
In the science realm we call for oceans to be incorporated into the
President's American Competitiveness Initiative, for the expansion of
ocean research and exploration initiatives, and building a strong
Integrated Ocean Observing System to monitor, observe, map, and analyze
changes in our oceans, coasts, and Great Lakes. A final area that
demands attention, but always seems to be ignored, is support of
education and outreach, for without an informed public there will be a
lack of political will and scientific expertise to move us toward more
sustainable management strategies. Again, I would refer Members of the
Committee and Committee staff to our ``From Sea to Shining Sea'' report
for more detailed funding recommendations.
______
Attachment
Addressing Oceans and Climate Change in Federal Legislation
July 2007
Introduction
The purpose of this paper is to provide Congress with information
and recommendations to support the enactment of legislation that
incorporates ocean science, management, and education into a national
initiative to mitigate and adapt to climate change. This initiative
must complement ongoing efforts to understand, monitor, and forecast
changes associated with natural variability, such as El Nino and the
Pacific Decadal Oscillation, since anthropogenic climate change will
also impact the frequency, pattern, and severity of these natural
processes. The goal is to improve our collective understanding of the
role of the oceans in climate change in order to inform policies and
strategies intended to reduce the vulnerability of and increase the
resiliency of our economic and ecological systems to impacts associated
with climate change. It is the Joint Ocean Commission Initiative's view
that this goal can best be met through a broad national climate change
response strategy that includes an emphasis on the oceans role in
climate-related processes.
After consultation with leading experts in ocean and climate change
science and policy, the Joint Ocean Commission Initiative suggests that
Congress address the link between oceans and climate change by
addressing needs in two key areas: governance reform and science.
Clearly, additional funding will be necessary to make sustained
progress in both areas. The actions recommended by the Joint Ocean
Commission Initiative are summarized below and discussed in more detail
in the pages that follow.
Governance Reform
1. Charge the National Academy with recommending a process and
strategy to respond to climate change, including consideration
of the organization and functions of a National Climate Change
Response Office responsible for guiding Federal programmatic
and budgetary climate change activities.
2. Codify and strengthen the White House Committee on Ocean
Policy, and give it a key role in supporting the activities of
the Climate Change Response Office.
3. Codify and strengthen the National Oceanic and Atmospheric
Administration (NOAA), realigning the agency's organizational
structure to enhance and focus its capacity to provide climate-
related services and improve ocean and coastal management.
4. Require a biennial integrated assessment of the Nation's
progress toward meeting its objectives to mitigate and adapt to
impacts associated with climate change and variability.
5. Require the submission of an integrated budget to
consolidate and highlight priorities established by the
National Climate Change Response Office that would accompany
the President's annual budget request.
Science Requirements
1. Request prioritization of and provide funding to implement
the Administration's Ocean Research Priorities Plan and
Implementation Strategy, with a focus on developing a science
enterprise that is responsive to societal and environmental
concerns.
2. Enact legislation authorizing the implementation of an
Integrated Ocean Observing System, incorporating both coastal
and global components.
3. Fund major ocean observation research and monitoring
infrastructure systems and supporting science and data
management programs, such as an Integrated Ocean Observing
System, the Ocean Observatories Initiative, research vessels,
and remote sensing programs.
4. Enhance funding support for transitioning ocean and
atmospheric data collection and synthesis programs from
research to operational status, with ongoing engagement of the
ocean science community in the operation, evaluation, and
evolution of the programs.
5. Support research to evaluate the impact of greenhouse gas
mitigation policies on coastal and ocean processes and
ecosystem health (e.g., oceanic carbon sequestration, biofuel
production).
The Role of Oceans in Climate Change
Increasing awareness and concerns about climate change have
elevated the urgency to take action to mitigate its causes and make
preparations to adapt to its anticipated economic and environmental
impacts. At continental, regional, and ocean basin scales, numerous
long-term changes in climate have been observed. These include changes
in arctic temperatures and ice, as well as widespread changes in, ocean
salinity, wind patterns, the quantity of precipitation, and various
aspects of extreme weather.\1\ As Congress moves forward in developing
climate change policies, the accompanying legislation should recognize
the fundamental role oceans play in governing climate change and Earth-
related processes. Some important facts regarding the relationship
between oceans and climate change include the following:
---------------------------------------------------------------------------
\1\ Intergovernmental Panel on Climate Change. 2007. Report of
Working Group I The Physical Science Basis.
Oceans cover 71 percent of the Earth's surface and average
---------------------------------------------------------------------------
over 12,200 feet in depth.
Water holds approximately 1,000 times the amount of heat as
air, and the interaction between ocean circulation and the
global distribution of heat is the primary driver of climatic
patterns.
The oceans are warming, particularly since 1950s, with
global mean sea surface temperature having increased roughly
one degree Fahrenheit in the 20th century.\2\
---------------------------------------------------------------------------
\2\ Doney, Scott. 2006. The Dangers of Ocean Acidification.
Scientific American (March).
Sea levels rose 7 inches during the 20th century and nearly
---------------------------------------------------------------------------
1.5 inches between 1993 and 2003 alone.\2\
Oceans are a major carbon sink and have absorbed fully half
of all fossil carbon released to the atmosphere since the
beginning of the Industrial Revolution.\2\
The absorption of carbon has resulted in increasing ocean
acidification, impacting the health of marine ecosystems and
species, including, but not limited to, those with carbonate-
based skeletons (e.g., corals), as well as influencing the
important role ocean plays in the global cycling of carbon.
Little to no Arctic sea ice is expected in the summers by
2100.\2\
Governance Reform to Address Oceans and Climate Change
Climate change involves complex and dynamic interactions of the
atmosphere, ocean, land, their related ecosystems, and human
activities. The complexity and breadth of issues associated with
efforts to understand, mitigate, and adapt to climate change, the scale
of its impacts from the local to the global level, and the need to
understand the relationship between natural variability and climate
change make it essential that the Nation have a coherent and
comprehensive strategy to address this new challenge.
Unfortunately, there is general agreement in the scientific
community that the current Federal climate change governance regime is
too limited in scope and must be expanded if it is to be truly
comprehensive. A Climate Change Response Office is required to guide
the development and implementation of a National Climate Change
Response Strategy. Such an office must have the authority to direct the
activities of multiple Federal agencies and have a strong role in the
budget formulation process. This will require designing and
implementing a strategy that balances the need to conduct basic and
applied research, monitoring and analysis, and modeling and
forecasting, with the goal of translating data into information
products that can be used to develop sound policies to mitigate and
adapt to environmental and socioeconomic impacts stemming from climate
change.
Ocean science and management must be recognized as key elements of
a national response strategy. Thus, the existing interagency
coordination process operating under the White House Committee on Ocean
Policy \3\ should be codified and charged with supporting the effort to
institutionalize a broader National Climate Change Response Strategy.
An additional action needed to strengthen the Federal Government's
capacity to respond to climate change is to codify and strengthen the
National Oceanic and Atmospheric Administration (NOAA). As a key
provider of climate-related services and ocean management information,
and as one of the principle agencies investigating the ocean's role in
climate variability, NOAA plays a lead role in matters related to
climate change. However, an outdated organizational structure and the
lack of resources have limited NOAA's ability to fulfill its multiple
mandates. The opportunity is ripe for Congress to reevaluate NOAA's
organizational structure and realign programs along its core functions:
environmental assessment, prediction, and operations; scientific
research and education; and marine resource and area management.
Strengthening NOAA and realigning its functions would greatly enhance
its capacity to provide climate-related services and facilitate the
implementation of proactive management measures to mitigate anticipated
impacts on coastal economies and ecosystems.
---------------------------------------------------------------------------
\3\ Executive Order 13366, 2004.
---------------------------------------------------------------------------
Finally, Congress should require a biennial integrated assessment
of the Nation's progress toward mitigating and adapting to climate
change impacts. An integrated assessment evaluating the collective
effort of Federal programs and activities will provide a baseline from
which to measure progress and will help ensure the Nation is maximizing
the use of available data and information to improve the caliber of
forecasts and to evaluate the effectiveness of management actions. An
additional step that would facilitate better integration of Federal
programs would be a requirement for the submission of an integrated
budget that clearly identifies priorities established by the proposed
National Climate Change Response Office and how those priorities relate
to and complement efforts directed at understanding the ocean's role in
climate change. Congressional oversight of the Federal budget is its
most powerful tool, but Congress' capacity to help guide a response to
an issue as complex as climate change is compromised when information
is dispersed throughout the President's budget.
Ocean and Coastal Science Requirements
Credible and timely scientific information will be essential as the
Nation begins the process of responding to the challenges associated
with climate change. Better science, when linked with improved risk
management and adaptive management strategies, will help guide a
process that must deal with the relatively high levels of uncertainty
related to mitigation alternatives and the range of impacts associated
with climate change and variability. A much more comprehensive and
robust science enterprise that incorporates a better understanding of
the ocean's role in climate change is required to forecast more
accurately the magnitude and intensity of this change at multiple
scales, as well as to evaluate options for mitigation and adaptation.
This process must also include strengthening capacity in the social
sciences, whose contributions will influence risk and adaptive
management strategies significantly given the immense economic impact
climate change will have on coastal communities.
Unfortunately, the existing ocean and coastal science enterprise
supporting climate change research, observations, data management, and
socioeconomic analysis is limited. Despite the unprecedented
opportunities to capitalize on technological advances, future capacity
is compromised due to a lack of fiscal support for key infrastructure
and science programs. For example, the U.S. commitment to constructing
an observing system focused on studying physical ocean processes is
only half complete, while satellite systems responsible for generating
invaluable data across large areas of oceans are aging. The
construction of replacement systems are behind schedule, over budget,
and as currently configured, may have less capacity than the systems
they are replacing. The status of infrastructure supporting on and
underwater ocean science, such as ship, buoys, cabled observatories,
planes, and other underwater monitoring hardware, is bleak.
Additionally, support for shore-side lab work, where data for the
observing systems is analyzed, quality-controlled, synthesized, and
integrated, has eroded. Further underlying these weaknesses is a lack
of capability to transmit large amounts of ocean data in real-time and
a disjointed data management system that prevents scientists from fully
utilizing the data that are being collected now. Stagnant funding
supports only bare-bones research, monitoring, modeling, and analysis
enterprises that have difficulty providing the quantity and quality of
data needed to generate information with the relatively high levels of
confidence demanded by decisionmakers facing difficult policy choices.
Congress can begin to remedy this situation by taking the following
series of steps. First, it should call on the administration to
prioritize and request full funding to implement its Ocean Research
Priorities Plan and Implementation Strategy (ORPPIS). ORPPIS provides a
solid blueprint to guide research on the ocean's role in climate,
including the development of a comprehensive observing system and other
ocean-related research priorities that will improve our ability to
enhance the resiliency of marine ecosystems and coastal economies to
climate-induced changes. Particularly noteworthy in ORPPIS is its
emphasis on using improved understanding to provide better and timelier
policy and resource management decisions, relying on much stronger
support for social and economic research. It is the first comprehensive
research strategy developed by the Administration with input from the
ocean community and should be used by Congress to guide its ocean
science funding priorities.
Congress should also authorize and fund the implementation of an
Integrated Ocean Observing System (IOOS). Support for the
implementation of the coastal and global IOOS should be driven by a
cooperative interagency process that incorporates expertise from
outside the Federal system. Congressional support should also extend to
major observing initiatives supported by the National Science
Foundation, as well as to remote sensing satellite programs supported
by NASA's Earth Science program. As noted earlier, the loss or
diminishment of remote sensing capabilities, in addition to the lack of
support for transitioning ocean and atmospheric data collection and
synthesis program from research to operational status, has
significantly compromised our Nation's capacity to monitor the vast
expanse of the ocean. Sustained research and operational monitoring and
analyses programs supported by enhanced data collection, management,
and synthesis capabilities are the foundation of an observation system
that can refine climate change models and reduce the level of
uncertainty associated with their projections.
Finally, Congress should support research and science programs
focused on analyzing the potential impact various greenhouse gas
mitigation strategies may have on ocean and coastal processes and
ecosystem health. Recommendations for carbon sequestration in the
oceans will require particularly careful review, given our growing
concern about the sensitivity of marine ecosystems to changes in the
biogeochemistry of ocean waters as a result of increased absorption of
carbon dioxide, in particular ocean acidification. Similarly, increased
biofuel production will generate additional runoff of nutrients,
herbicides, and pesticides, further exacerbating pollution and nutrient
enrichment problems in coastal waters.
Given their immense size, fundamental role as a driver of climate
processes, and critical social and economic importance, it is
imperative that Congress focus greater attention and resources on
improving our understanding and management of our oceans, coasts, and
Great Lakes. The actions recommended above are important steps that
will lay the foundation for making great advances in ocean science and
allow meaningful progress toward improved stewardship of one of
nation's greatest natural resources.
______
Response to Written Questions Submitted by Hon. Maria Cantwell to
James D. Watkins
Question 1. Admiral Watkins, do you think that policymakers should
specifically take ocean impacts into account when setting emissions
reductions targets? Do current emissions reduction targets sufficiently
consider ocean impacts? How do you think policymakers should
incorporate ocean impact concerns when setting emissions reduction
targets?
Answer. I cannot say how much consideration climate scientist and
policymakers are giving to impacts on ocean-related chemistry and
ecology as they evaluate various emission reduction scenarios. However,
I strongly suspect that it is inadequate, particularly in light of the
testimony presented at the hearing suggesting that atmospheric carbon
dioxide levels in excess of 450 ppm may have the potential of
sufficiently increasing the acidity of surface ocean water to levels
that would begin to jeopardize phytoplankton productivity and the
capacity of other carbonate-extracting species from forming shells and
skeletons.
It is this concern and others that are driving the Joint
Initiative's effort to elevate awareness of the role of oceans in
climate processes. In order for policymakers to make informed and
balanced decisions regarding the incorporation of ocean-related
concerns in the emission reduction targeting process, they should
pursue two strategies. First, they should support additional ocean
science to get a better understanding of natural variability in the
system, and how the accumulation of human-generated emissions are
exacerbating this variability and driving other changes. Second, given
the fact that acquiring this information will take some time,
policymakers should strongly consider taking a precautionary approach
in the target setting process. By this I mean taking a prudent,
balanced approach that acknowledges the vulnerability of the ocean
ecosystem to dramatic increases in carbon-based emissions, while also
recognizing the multiple economic benefits and services provided by our
oceans, coasts, and Great Lakes. As more information become available,
the framework developed should be flexible and capable of adapting to
new information. I remain very concerned about the short-sightedness of
prior policies that contributed to the degradation of our oceans and
coasts and strongly encourage a new strategy that incorporates full
consideration of the health of our oceans and coastal communities into
the decisionmaking process.
Finally, given the increased focus on identifying technologies
capable of capturing carbon dioxide and other greenhouse gases; it is
imperative that support for these efforts include funding to study the
potential impact of storing these gases in or under our oceans. We now
have a much better appreciation for the sensitive ecological balance in
our oceans and must take great care not to further exacerbate existing
problems by assuming our oceans are capable of further degradation.
Question 2. Admiral Watkins, how can we improve our ocean and Earth
observation programs to ensure understanding of the impacts of global
climate change and ocean acidification on the marine environment?
Answer. Perhaps the single most important step we can make is to
implement and fully fund an Integrated Ocean Observing System (IOOS).
The Joint Initiative reiterates this point in its recent climate change
and oceans paper, which I reference in my response to Chairman Inouye's
questions, as well as in our report to Congress, ``From Sea to Shining
Sea.'' The IOOS system, as conceived by the ocean science community,
covers the spectrum of observations. This system includes a progression
of activities and programs, starting with studying and understanding
ongoing physical, chemical, and biological processes occurring in the
oceans and along our coasts, to gain a better knowledge of how various
components within the system operate and interact. The second element
of the strategy includes developing and implementing systematic and
sustainable observation systems, consisting of remote (satellite), in
situ (buoys, stationary sensors), and mobile platforms (vessels, SUVs),
that provide a steady accounting of changes in system processes. The
third element is to use this information to refine climate and ocean
models, increasing their capacity to provide credible and accurate
forecasts of changes in the functioning of natural systems.
There are significant infrastructure costs associated with
establishing such a system, as well as support for the synthesis and
integration of the wealth of information generated by the system.
However, the costs associated with this effort are minimal given the
significant fiscal benefits resulting from the improved accuracy,
credibility, and reliability a comprehensive earth observation system
will provide. The information provided by a fully operational IOOS will
be invaluable as Congress and other policymakers wrestle with difficult
policy decisions that have significant socioeconomic impacts, not the
least of which will be determining an appropriate target for emission
reductions.