Antarctic ice shelf collapses in runaway disintegration, putting larger area at risk

Source: Associated Press

WASHINGTON: A chunk of Antarctic ice nine times the size of New York's Manhattan Island has collapsed suddenly and put an even larger glacial area at risk.

Satellite images show the runaway disintegration of a 220-square-mile (570-square-kilometer) chunk in western Antarctica. British scientist David Vaughan says it is the result of global warming.

The rest of the ice shelf, the size of the U.S. state of Connecticut, is holding on by a narrow beam of thin ice. Scientists worry that it too may collapse. Larger and more dramatic ice collapses occurred in 2002 and 1995.

Antarctica's Wilkins Ice Shelf Risks Collapse, U.K. Group Says
By Alex Morales

March 25 (Bloomberg) -- An Antarctic ice shelf bigger than Connecticut risks collapse because of global warming after a retreat that began on Feb. 28, the British Antarctic Survey said.

The Wilkins ice shelf, which lost 1,000 square kilometers (390 square miles) of ice, or about 6 percent of its surface, in 1998, calved another 570 square kilometers since February, the survey group said in an e-mailed statement. Now, there's little to stop the loss of another several thousand square kilometers.

``The rest seems to be held a bit by a thread,'' David Vaughan, a scientist at the group who in 1993 predicted Wilkins would break apart within 30 years, said today in a telephone interview from Cambridge, England. ``We predicted it would happen, but it's happened twice as fast as we predicted.''

The collapse of Wilkins would have few implications for sea levels because it's already floating and doesn't hold back large land-based glaciers, Vaughan said. Still, it may foreshadow future melting in the southern continent, which combined with Greenland holds enough ice to raise sea levels by 64 meters.

``The importance of it is it's further south than any ice shelf we've seen retreating before, it's bigger than any ice shelf we've seen retreating before and in the long term it could be a taste of other things to come if climate change continues in the Antarctic,'' Vaughan said.

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Antarctic shelf 'hangs by thread'
By Helen Briggs
Science reporter, BBC News

A chunk of ice the size of the Isle of Man has started to break away from Antarctica in what scientists say is further evidence of a warming climate.

Satellite images suggest that part of the ice shelf is disintegrating, and will soon crumble away.

The Wilkins Ice Shelf has been stable for most of the last century, but began retreating in the 1990s.

Six ice shelves in the same part of the continent have already been lost, says the British Antarctic Survey (BAS).

Professor David Vaughan of BAS said: "Wilkins is the largest ice shelf on the Antarctic Peninsula yet to be threatened.

"I didn't expect to see things happen this quickly. The ice shelf is hanging by a thread - we'll know in the next few days or weeks what its fate will be."

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http://news.bbc.co.uk/1/hi/sci/tech/7313264.stm

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