Climate change: Prepare for global temperature rise of 4C, warns top scientist

[Christa]

The UK should take active steps to prepare for dangerous climate change of perhaps 4C according to one of the government's chief scientific advisers.

In policy areas such as flood protection, agriculture and coastal erosion Professor Bob Watson said the country should plan for the effects of a 4C global average rise on pre-industrial levels. The EU is committed to limiting emissions globally so that temperatures do not rise more than 2C.

"There is no doubt that we should aim to limit changes in the global mean surface temperature to 2C above pre-industrial," Watson, the chief scientific adviser to the Department for the Environment, Food and Rural Affairs, told the Guardian. "But given this is an ambitious target, and we don't know in detail how to limit greenhouse gas emissions to realise a 2 degree target, we should be prepared to adapt to 4C."

Globally, a 4C temperature rise would have a catastrophic impact.

According to the government's 2006 Stern review on the economics of climate change, between 7 million and 300 million more people would be affected by coastal flooding each year, there would be a 30-50% reduction in water availability in Southern Africa and the Mediterranean, agricultural yields would decline 15 to 35% in Africa and 20 to 50% of animal and plant species would face extinction.

http://www.guardian.co.uk/environment/2008/aug/06/climatechange.scienceofclimatechange