PARIS: The world's top climate scientists said on Friday that global warming was man-made, spurring calls for urgent government action to prevent severe and irreversible damage from rising temperatures.
The UN Intergovernmental Panel on Climate Change (IPCC), which groups 2,500 scientists from more than 130 countries, released a landmark report predicting more droughts, heatwaves, rains and a slow gain in sea levels that could last for more than 1,000 years.
The report put the probability of the link between human activity and global warming at more than 90%, against the 66 to 90% likelihood it had signalled in 2001.
"Clearly we are endangering all species on earth, we are endangering the future of the human race," IPCC chairman R K Pachauri said.
"We are probably beyond the stage where we could have called it urgent. I would say it is immediate," he said, referring to the need for governments to act to reduce emissions.
Environmental campaigners urged the US and other industrial nations to significantly cut their emissions of greenhouse gases in response to the report.
"Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global mean sea level," the report said.
It said man-made emissions of greenhouse gases can already be blamed for fewer cold days, hotter nights, killer heat waves, floods and heavy rains, devastating droughts, and an increase in hurricane and tropical storm strength — particularly in the Atlantic Ocean.
Temperatures are likely to rise by 1.1 to 6.4 degrees Celsius (a wider range than in the 2001 report) by the year 2100, with a probable 2 to 4.5 degree range if carbon dioxide doubles from pre-industrial levels, the report said. Sea-level gain by the end of the century may range from 18 to 59 cm; an additional 10-20 cm are possible if recent, surprising melting of polar ice sheets continues.
The Kyoto Protocol is the main plan for capping greenhouse gas emissions until 2012 but it has been severely weakened since the US, the top source of greenhouse gases, pulled out in 2001. Emissions by many backers of Kyoto are far over target.
"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.”
