Sea levels rise faster, says study

DOHA—Sea levels are rising 60 percent faster than United Nations (UN) projections, threatening low-lying areas from Miami to the Maldives, a study said on Wednesday.

The report, issued during UN talks in Qatar on combating climate change, also said temperatures were creeping higher in line with UN scenarios, rejecting hopes the rate had been exaggerated.

“Global warming has not slowed down, (nor is it) lagging behind the projections,” said Stefan Rahmstorf, lead author at the Potsdam Institute for Climate Impact Research that compared UN projections to what has actually happened from the early 1990s to 2011.

The study said sea levels had been rising by 3.2 mm a year according to satellite data, 60 percent faster than the 2 mmannual rise projected by the UN’s Intergovernmental Panel on Climate Change (IPCC) over that period.

“This suggests that IPCC sealevel projections for the future may also be biased low,” the authors from Germany, France and the United States wrote in the journal Environmental Research Letters.

The IPCC’s latest report in 2007 said seas could rise by between 18 and 59 cm this century, not counting a possible acceleration of the melt of the Greenland and Antarctic ice sheets that could add more still water to the oceans.

In the last century, seas rose by about 17 cm.

Rahmstorf told Reuters his best estimate for sea level rise was between 50 cm and a meter this century, possibly more if greenhouse gas emissions surged. Higher temperatures would melt more ice on land and expand the water in the oceans.