By CHRIS ADAMS
Staff Reporter of THE WALL STREET JOURNAL
WASHINGTON -- A scientific panel convened at the request of the White House says that global warming is "real" and has "been particularly strong within the past 20 years," giving fodder to critics of President Bush's environmental policies just as he is set to discuss the issue on his pending European trip.
While acknowledging the uncertainties in global climate research, the National Research Council committee essentially endorsed the prevailing, but still disputed, scientific consensus on global warming. "We know that greenhouse gases are accumulating in Earth's atmosphere, causing surface temperatures to rise," said the panel's chairman, Ralph Cicerone, chancellor of the University of California at Irvine. "We expect the warming to continue because of greenhouse-gas emissions."
In March, when the president backed off a pledge to cap emissions of carbon dioxide, he explained his actions to a group of senators active on the issue, noting the "incomplete state of scientific knowledge of the causes of, and solutions to, global climate change." The president's position helped further undermine U.S. political support for the Kyoto Protocol, an international agreement intended to curtail global warming.
Last month, the White House wrote the National Academy of Sciences and its adjunct, the NRC, asking for help in "identifying the areas in the science of climate change where there are the greatest certainties and uncertainties." The White House also wanted an analysis of a recent report by the Intergovernmental Panel on Climate Change that detailed the potential extent of global warming in coming decades.
The National Research Council report, which was sent to the White House, noted that temperatures at the Earth's surface rose by about one degree Fahrenheit during the 20th century and that computer models suggest they will rise between 2.5 degrees and 10.4 degrees Fahrenheit by the end of this century. The panel noted that the result of warming is evident in "retreating glaciers, thinning Arctic ice, rising sea levels, lengthening of the growing season in many areas, and earlier arrival of migratory birds."
While the report, developed by a panel of scientific experts including one Nobel Prize winner, didn't generally come to new scientific conclusions, it reaffirmed the prevailing view among many scientists and supported the IPCC's sometimes-controversial work. Dr. Cicerone said his panel found the IPCC's conclusions "pretty sound and very voluminous and exhaustive."
Among other things, Dr. Cicerone's committee explored whether human activity is causing climate change, concluding that changes of the past several decades are "likely mostly due to human activities." But, the report goes on, "we cannot rule out that some significant part of these changes are also a reflection of natural variability."
Don Ritter, a former member of Congress and now chairman of the National Environmental Policy Institute, a think tank here, said the panel members "to some extent endorsed the occurrence of global climate change -- but it's not a ringing endorsement. They are quick to point out uncertainties. ... There's enough there for both sides to take and run with."
Given the uncertainties that remain, the panel called for "a strong commitment" to basic research as well as better climate models and an improved climate-observing system.
A White House spokeswoman said the report would be "extremely helpful in understanding what is known and what is not known" as the administration debates global-warming policy.
Write to Chris Adams at firstname.lastname@example.org
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