Diminuer l'effet de serre est envisageable

Published online: 4 May 2007; | doi:10.1038/news070430-11 / http://www.nature.com/news/2007/070430/full/070430-11.html

Tackling greenhouse gases looks to be affordable

International report sets out costs of bringing down global emissions.

Michael Hopkin

Bringing greenhouse gas emissions under control looks to be both achievable and affordable, on the basis of the most recent report of the Intergovernmental Panel on Climate Change (IPCC).

Today marks the end of an often fraught week of talks by the IPCC's Working Group III, which evaluates strategies to counter the rising levels of greenhouse emissions.

Their summary report, released in Bangkok, Thailand, says that stabilizing atmospheric greenhouse gases at a level likely to avoid the worst effects of global warming would cost no more than 3% of global economic productivity by 2030 - an average of 0.12% per year.

This is cheaper than many observers had expected it to be, and most see it as affordable; environmental groups represented on the panel, such as Greenpeace, have called it a small price to pay.

But US officials say that this would lead to a global recession, and argue that greenhouse levels should be stabilized at a higher level. "This report underscores the importance of a strong curve of emissions reductions," says James Connaughton, chair of the White House Council on Environmental Quality. "But no world leader will pursue a strategy that would lead to economic recession."