Former Vice President Al Gore, who has waged a decades-long fight against global warming, on Friday shared the Nobel Peace Prize with a Geneva-based United Nations climate group. The choice of Gore delivered a symbolic rebuke to the Bush administration, which has opposed calls for mandatory greenhouse gas reductions, and fueled speculation that the former Democratic presidential candidate might yet enter the 2008 race.
In its citation, the Nobel committee said Gore's commitment "has strengthened the struggle against climate change" and called him "probably the single individual who has done most to create greater worldwide understanding of the measures that need to be adopted."
The 2006 Oscar-winning documentary "An Inconvenient Truth," which captured Gore's crusade, has been credited with helping push global warming into the public consciousness.
Gore, 59 -- who has insisted he does not plan to run for office again -- said Friday that he was deeply honored to receive the peace prize and that he and his wife, Tipper, would donate his half of the $1.5-million award money to the nonprofit Alliance for Climate Protection, which he founded.
"We face a true planetary emergency," Gore said. "The climate crisis is not a political issue, it is a moral and spiritual challenge to all of humanity. It is also our greatest opportunity to lift global consciousness to a higher level."
If Gore made global warming a cause celebre, the U.N.'s Intergovernmental Panel on Climate Change, a group of more than 2,000 scientists from 130 countries, has provided the scientific heft. Its series of reports released this year definitively blamed humans for global warming and said that rising temperatures, if left unchecked, would lead to widespread coastal flooding, starvation and species extinction.
"This prize belongs to the international U.N. community and the states that support us," the IPCC's chairman, Rajendra Pachauri, said from his offices in New Delhi. By bestowing the honor on those sounding the alarm against global warming, he said, the Nobel panel elevated a problem that has "the potential to disrupt stability and peace all over the world."
When the U.N. climate group was formed nearly two decades ago, scientists were divided over whether human activities were causing climate change. But as evidence mounted, a broad consensus began to emerge that the connection was real.
The White House has opposed joining the Kyoto Protocol -- a U.N.-led treaty to reduce global greenhouse gases that Gore helped negotiate when he was vice president -- on the grounds that it does not restrict emissions in the developing world, where pollution is worsening most rapidly. Instead of mandating greenhouse gas cuts, the Bush administration places its hopes on voluntary reductions and future technologies.
The Kyoto treaty was signed by the Clinton administration but was not submitted to Congress, then dominated by Republicans, for ratification.
"Almost inevitably [the 2007 peace prize] will be taken as some sort of statement on the U.S. policy -- or lack thereof," said John Reilly, an economist at the Massachusetts Institute of Technology. "For those people who have been skeptical about global warming, the Nobel Prize is a broad societal recognition of its importance."
Skeptics were not swayed.
"In terms of Al Gore, it's a wonderful award that recognizes the brilliance of Hollywood promotional activity," said John R. Christy, director of the Earth Systems Science Center at the University of Alabama in Huntsville. "He has really created an astounding career and a mega-fortune by demonizing energy."
Christy, a lead author in the IPCC's 2001 report, has criticized Gore's dire predictions about the effect of global warming.
The economic forces against cutting emissions of heat-trapping gases are enormous, particularly in the developing world.
China, whose annual greenhouse gas emissions are expected to surpass those of the U.S. as soon as this year, opens a new coal-fired power plant every week.
"Their entire base of power and incentive structure since Mao Tse-tung has been based on growth," said Michael Gillenwater, a climate policy researcher at Princeton University.
At the same time, because carbon dioxide remains in the atmosphere for decades, the United States bears the most responsibility for current greenhouse gas concentrations.
"You're always looking for some kind of event that will catalyze action," Gillenwater said, suggesting the Nobel award was not enough to make nations rethink how they affect global warming.
A hurricane hitting Manhattan, he added, might do the trick.