Mankind to blame for global warming say scientists
Friday, February 2, 2007; 4:13 PM
PARIS (Reuters) - Mankind is to blame for global warming, the world's top climate scientists said on Friday, sending governments a "crystal clear" warning they must take urgent action to avert damage that could last centuries.
The United Nations panel, which groups 2,500 scientists from more than 130 nations, predicted more droughts, heatwaves and a slow gain in sea levels that could continue for more than 1,000 years even if greenhouse gas emissions were capped.
The panel's report predicts a "best estimate" that temperatures would rise by between 1.8 and 4.0 Celsius (3.2 and 7.8 Fahrenheit) in the 21st century.
"Faced with this emergency, now is not the time for half measures. It is the time for a revolution, in the true sense of the term," French President Jacques Chirac said. "We are in truth on the historical doorstep of the irreversible."
The scientists said it was "very likely" -- or more than 90 percent probable -- that human activities led by burning fossil fuels explained most of the warming in the past 50 years.
That is a toughening of the position taken by the Intergovernmental Panel on Climate Change's (IPCC) last report in 2001, which judged a link as "likely," or 66 percent probable.
Many governments, U.N. agencies and environmental groups urged a widening of the U.N.'s Kyoto Protocol, which binds 35 industrial nations to cut emissions by 2012 but excludes top emitters led by the United States, China and India.
"The signal we've received from the scientists today is crystal clear and it's important that the political response is also crystal clear," said Yvo de Boer, head of the U.N. Climate Secretariat.
He wants an emergency environment summit of world leaders this year to push for wider action. Kyoto has been weakened since the United States pulled out in 2001 and emissions by many backers of Kyoto are far above target.
The Bush administration played down the U.S. contribution to climate change although the country is the biggest single source of greenhouse gases, with a quarter of the world total.
"We are a small contributor when you look at the rest of the world," U.S. Energy Secretary Sam Bodman said of greenhouse gas emissions after the IPCC report. "It's really got to be a global discussion."