Can Global Warming Be Studied Too Much?
December 3, 2002
By ANDREW C. REVKIN
WASHINGTON, Dec. 2 - On Tuesday, the Bush administration
convenes a three-day meeting here to set its new agenda for
research on climate change. But many climate experts who
will attend say talking about more research will simply
delay decisions that need to be made now to avert serious
harm from global warming.
President Bush has called for a decade of research before
anything beyond voluntary measures is used to stem tailpipe
and smokestack emissions of heat-trapping gases that
scientists say are contributing to global warming.
"When you're speeding down the road in your car, if you've
got to turn around and go the other direction, the first
thing is to slow down, then stop, then turn," said David K.
Garman, the assistant secretary of energy for energy
efficiency and renewable energy.
But many climate experts say the perennial need for more
study can no longer justify further delays in emission
"Waiting 10 years to decide is itself a decision which may
remove from the table certain options for stabilizing
concentrations later," said Dr. Michael Oppenheimer, a
professor of geosciences at Princeton.
For example, under today's rate of emissions growth, he and
other experts say that certain losses are already probable,
including dwindling of snow-dependent water supplies and
global die-offs of vulnerable ecosystems like coral reefs,
alpine meadows and certain coastal marshes.
Nevertheless, administration officials say further research
is still necessary because scientists cannot say exactly
what effects human activity will have on global climate and
how dangerous they will be. It is worth taking the time to
conduct more analysis at least to clarify the balance of
environmental and economic risks, they say.
"Science rarely gives enough information to narrow policy
choices to a single option, but it can clear away some of
the underbrush," said Dr. John H. Marburger III, assistant
to the president for science and technology.
Some energy and climate experts have run new kinds of
analyses showing that there is still time to avoid the
worst effects of climate change while also limiting
economic costs involved with an abrupt shift from fossil
fuels, the main source of the warming gases.
The meeting, involving hundreds of experts, will be the
biggest public airing of arguments in many years.
Most scientists concur on the basics. Atmospheric levels of
the heat-trapping gases, mainly carbon dioxide from burning
coal and oil, have increased by more than a third since the
start of the Industrial Revolution, and there is wide
agreement that they will probably double from preindustrial
concentrations by the end of the century, driven by energy
demands of developing countries.
International and American panels of experts have concluded
that these gases have caused most of the warming trend over
the last 50 years. But there is still a wide range of
projections indicating how much warmer things may get, how
storm and drought patterns may respond and what the effects
will be on ecosystems, agriculture and health. These
uncertainties are unlikely to be dispelled soon. But many
climate experts say that some effects can reasonably be
predicted and that prudence calls for more action now.
Dr. Warren M. Washington, a senior scientist at the
National Center for Atmospheric Research, likened the
situation to the debate over smoking's link to cancer.
"Even with smoking, it's still basically a statistical
thing," said Dr. Washington, who is chairman of the
National Science Board, a panel that advises the White
House and Congress. "But vested interests do not want to
take action based on early indications, and with climate
early indications is what we have."
If greenhouse gas concentrations double, climate experts
expect substantial disruptions of ecosystems and water
supplies, coastal damage as sea levels rise and intensified
drought and downpour cycles. Even more calamitous surprises
could lie in store, including disruptions in the Atlantic
Ocean currents that help warm Europe.
The experts concede that they cannot say exactly what may
happen, or when. Also, changes will probably occur slowly -
sea levels rising by millimeters a year, say - so there
will be no one event to prompt people to choose a
fuel-saving hybrid car over a gas-guzzling S.U.V.
But the warming will have enormous momentum, they say.
Unlike soot or sulfur pollution, which falls out of the
atmosphere within days or weeks, molecules of carbon
dioxide and other greenhouse gases can circulate for a
century or more.
As a result, scientists say, allowing things to go on as
they are is like making minimum payments on a credit card
while still using it: the balance grows and grows.
In the long run, almost all experts agree, stabilizing
carbon dioxide concentrations in the atmosphere will be a
century-plus process that will necessitate eliminating - or
capturing - all releases of carbon dioxide from burning
coal, oil and other fossil fuels.
That will require a fundamental shift to energy
technologies that do not yet exist. But it also requires
emission cuts in the next decade or so, even as trends for
such emissions are sharply up.
"We will probably need everything in the tool kit to cut
emissions enough to stop the worst things from happening,"
said David D. Doniger, the director of climate policy for
the Natural Resources Defense Council, a private group. "A
long-term technology program is definitely in order, but we
also need to be acting now with the technology available
But the Bush administration is resisting calls for quick
action. Its focus on more research comes straight from the
president. In his first speech on climate, in June 2001,
Mr. Bush defended the need for more research by saying, "No
one can say with any certainty what constitutes a dangerous
level of warming, and therefore what level must be
In February, he reaffirmed the country's commitment to
pursue the goal of a climate treaty his father signed in
1992: to stabilize greenhouse gas concentrations at a level
that will prevent dangerous interference with the climate.
But he has rejected the instrument chosen by almost all
other industrialized countries to start on a path toward
that goal, the 1997 agreement called the Kyoto Protocol. It
requires industrialized countries that submit to its terms
to reduce greenhouse-gas emissions by 2012 to levels below
those measured in 1990.
Instead, Mr. Bush calls for voluntary actions.
from now, if scientists still think climate change is
worrisome, other strategies may follow, he said.
Although many climate experts say delays are risky, others,
including Dr. James A. Edmonds of the Energy Department's
Pacific Northwest National Laboratory, have calculated that
Mr. Bush's timetable and prompter actions like the Kyoto
treaty do not lead to significantly different outcomes in
the long run. The most critical challenge by far, he said,
is the sharp decline in emissions in midcentury.
Other scientists whose views are embraced by industry say
there still isn't enough evidence for quicker action.
"We are still struggling with the `what will be' question,
especially at regional scales, which makes answering the
`what will be dangerous' question too difficult to handle,"
said one of these researchers, Dr. John R. Christy, the
director of the Earth System Science Center at the
University of Alabama in Huntsville.
As a result, he said, any emissions plan should be
The meeting this week is likely to see many clashes between
the two camps, with more than 1,000 scientists, industry
lobbyists, environmental campaigners and others planning to
Sam Thernstrom, a spokesman for the White House Council on
Environmental Quality, says the goal is to hear all views
before the research plan is finished next spring and a
series of two- to five-year projects is begun.
"Anyone who has quibbled with how this plan is put
together," he said, "they and the rest of the world are
invited to come on down and make suggestions. All ideas
will be considered."
Those eager for more aggressive actions say they doubt the
meeting will lead to significant policy shifts,
particularly now that relevant Congressional committees are
controlled by Republicans pushing for more, not less,
exploitation of fossil fuels.
They also say that the administration's 170-page research
plan (available on the Web at www.climatescience.gov)
includes no commitments that adequate money will flow to
support new science.
To build a more convincing case for faster action, a
growing group of researchers is trying new ways of
conveying the risks of certain emissions paths, including
pinpointing when actions have to start to stabilize
greenhouse gases at particular levels.
The current concentration of carbon dioxide in the
atmosphere is 370 parts per million, and the level before
industrialization began was about 280 parts per million.
Under what is considered a best-case model, global annual
emissions of carbon dioxide will have to start declining by
2020 to stabilize atmospheric carbon dioxide at 450 parts
per million. Even at that level, there would probably be
substantial losses, Dr. Oppenheimer and others say,
including a global die-off of coral reefs.
Societies have probably already missed that turning point,
scientists say, and the longer societies wait to act, the
higher the eventual greenhouse plateau and the greater the
If emissions do not start declining until 2033, carbon
dioxide concentrations will plateau at 550 parts per
million - more than double preindustrial concentrations.
That level raises the likelihood of more calamitous
consequences, including intensified storm and drought
cycles, wider extinction of species and perhaps the
eventual freeing of the West Antarctic Ice Sheet, which
could raise sea levels a century or two from now 15 feet or
more, inundating coasts where most human settlements are
In between these extremes, some climate experts and
economists see a path that could avoid the worst
environmental and economic risks. The problem is that this
would depend on a fairly prompt start on emission
reductions and aggressive research on finding new sources
of nonpolluting energy.
There are other reasons for prompt action, experts say. One
is that energy providers like power plant owners plan their
investments in new equipment a decade or two ahead of time,
said Dr. David G. Victor, the director of the energy and
sustainable development program at Stanford.
Another problem with relying on more research, many climate
experts say, is the presumption that the extra effort will
reveal a "safe" level of greenhouse gases.
Better computer models and observations are likely to
refine the menu of impacts, but reducing uncertainty still
"doesn't necessarily provide what is needed by decision
makers," said Dr. Roger A. Pielke Jr., an expert on
environmental risk at the University of Colorado. Society
as a whole must answer those questions, he and other
"To avoid danger implies a threshold," said Dr. Henry D.
Jacoby, an economist at the Massachusetts Institute of
Technology and co-director of its program on the science
and policy of global change. "But with climate, I don't
believe there is one."
"There are so many different effects, in so many different
countries, in so many different sectors, affecting so many
different processes, affecting so many different people in
so many different situations that there's not going to be a
clearly defined break point," Dr. Jacoby said.
Dr. Jacoby likened the situation to a doctor-patient
conference, when the patient learns that his high
cholesterol puts him at risk for a heart attack.
"Is your next question `Tell me exactly when my heart
attack is coming and how serious it will be?' " Dr. Jacoby
said. "No. You want to know what you can do about it now."
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