Top climate scientists meeting in Copenhagen say that sea levels could rise twice as much as previously projected.
They say that low-lying coastal areas housing one-tenth of the world's population would be flooded unless greenhouse gas emissions are curbed substantially.
A 2007 report by the Intergovernmental Panel on Climate Change predicted a sea level rise of 18 to 58 centimetres by the end of the century.
But experts at a three-day conference said today that sea level rise could exceed one metre and is unlikely to be less than 50 centimetres.
The conclusions of the conference will be presented to politicians meeting in December to discuss a new global agreement on emissions.
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