Climate change is likely to pose an 'intolerable' threat to human health, food and water supplies, economic development and natural ecosystems, according to new research.
A study by German researchers suggests that the world can tolerate a rise of up to 2°C over pre-industrial levels. Beyond this, the effects of climate change would become severe, including melting of large ice sheets, and abrupt disturbances to the North Atlantic Ocean's currents and to monsoons in Asia.
Global mean temperatures have already increased by 0.6°C since 1990. The Intergovernmental Panel on Climate Change estimates that by the end of the 21st century, temperatures may increase by a further 1.4 to 5.8°C. Even the lower limit of this range would lead to 'intolerable' climate change, according to the German study.
Reference: Nature 426, 486 (2003)