Scientists in search of new consensus on climate change[fr][de] 

The IPCC  is putting the final touches to a 15-page summary of its Fourth Assessment Report on climate change at a meeting on 29 January-1 February in Paris.

The report will form the new scientific basis for policymakers in Europe, the United States and developing nations when they meet at the end of the year to discuss possible new measures to fight global warming after 2012 when the Kyoto Treaty's targets expire.

Like the previous editions, the report will be divided into three parts:

• The physical science basis (chapter outline );
• impacts, adaptation and vulnerability (chapter outline ), and; 
• mitigation of climate change (chapter outline ).

Meanwhile, a controversy broke out among climate scientists about the extent of future warming and related ice-melt with early drafts of the report predicting lower sea-level rises than expected.

The projections "don't take into account the gorillas - Greenland and Antarctica", said Lonnie Thompson, a polar-ice specialist at Ohio State University cited by the Associated Press.

The UN stepped into the debate on 30 January, when it published new data confirming the accelerated melting of mountain glaciers worldwide over the past two-and-a-half decades.

The controversy reflects the uncertainties that still prevail on climate change science. While few doubt that human activities such as fossil fuel burning exacerbate the greenhouse effect, scientists still struggle to produce consistent projections about future warming, which sparks heated arguments.

The IPCC meeting is seeking to put an end to this situation as scientists debate the new text word-by-word. The 15-page summary is expected to be published on 1 February. 

At EU level, the European Commission has proposed a 'unilateral' reduction of greenhouse gases of 20% by 2020, a target that goes beyond the 8% reduction it agreed to under the Kyoto Protocol in 2012. EU member states will decide whether to endorse this new target at a summit in March.