Leading climate scientists said today they were more certain than ever before that mankind was the main culprit of global warming in a report meant to guide governments in dealing with rising temperatures.
Following are the report’s findings agreed by the UN’s Intergovernmental Panel on Climate Change:
Human Responsibility
The panel raised the probability that human activities, led by the burning of fossil fuels, are the main cause of global warming since the mid-20th century to “extremely likely”, or at least 95 per cent, from “very likely” (90 per cent) in its previous report in 2007 and “likely” (66 per cent) in 2001.
Slowing Warming This Century
The panel said that short, individual periods, such as 1998 which was an exceptionally warm year, are influenced by natural variability and do not, in general, reflect long-term climate trends.
Projected Warming
The panel said temperatures were likely to rise by between 0.3 and 4.8 degrees Celsius by the late 21st century. The report uses new computer models that are not directly comparable with scenarios in 2001.
Sea Level Rise
Sea levels are likely rise by between 26 and 82 cm (10 to 32 inches) by the late 21st century, after a 19 cm rise in the 19th century. In the worst case, seas could be 98 cm higher in the year 2100. The 2001 report projected a rise of 18 to 59 cm, but did not take full account of a melt in Antarctica and Greenland.
Climate Sensitivity
The report estimates that a doubling of carbon dioxide concentrations in the atmosphere would lead to a warming of between 1.5 and 4.5 degrees Celsius , lowering the bottom of the range from 2.0 degrees estimated in 2007 report. The new range is the same as in other IPCC reports before 2007.