UK & World News
Ice Sheet Melt 'Past The Point Of No Return'
The huge West Antarctic ice sheet is melting at a faster pace than scientists had predicted and the thaw is irreversible, a new study has found.
The Nasa report said there is "nothing to stop the glaciers in this area from melting into the sea".
The study looked at 40 years of ground, airplane and satellite data.
Evidence shows "a large sector of the West Antarctic ice sheet has gone into a state of irreversible retreat", said Nasa glaciologist Eric Rignot, chief author of the study.
The development is likely because of man-made global warming and the ozone hole which have changed the Antarctic winds and warmed the water that eats away at the feet of the ice, researchers said.
"The system is in sort of a chain reaction that is unstoppable," Mr Rignot said.
"Every process in this reaction is feeding the next one."
This part of Antarctica would be a major contributor to sea level rise in coming decades and centuries, and the study sees eventually 4ft (1.2m) of sea level rise from the melt.
"It's passed the point of no return," Mr Rignot said.
"A conservative estimate is it could take several centuries for all of the ice to flow into the sea."
Curbing emissions from fossil fuels to slow climate change will probably not halt the melting but it could slow the speed of the problem, Mr Rignot said.