The Southern Big Melt

Further information on generalized melting by New Scientist:

"A thin strip of ice, just 6 kilometres wide, is all that is holding back the collapse of a huge ice shelf in Antarctica, according to glaciologists.

The Wilkins ice shelf – previously some 16,000 square kilometres in area – has been disintegrating fast. On 28 February, an iceberg 41 km long and 2.5 km wide broke off the ice shelf. This triggered the runaway disintegration of a further 570 square kilometres of ice.

"I would be very surprised if it survives more than a couple more melt seasons," says Ted Scambos of the University of Colorado, US.

Other researchers, including David Vaughan of the British Antarctic Survey, believe it could be gone within weeks. "The ice shelf is hanging by a thread – we'll know in the next few days or weeks what its fate will be," he says.

'Narrow brace'

Although researchers agree the disintegration of the Wilkins ice shelf will not contribute to rising sea levels, they say it may help them understand what triggers such events in order to predict when they are likely to happen again.

"There now remains just a narrow beam of ice, roughly 6 km wide, which is bracing the rest of the shelf," says Scambos. "If that beam breaks up, about half of the ice shelf will probably very quickly break apart."

However Scambos says this is not likely to happen this year, as the southern winter is settling in.

The break up is already helping researchers understand what triggers the disintegration of ice sheets. They now know that waves generated by storms over the open ocean are just as important as air and water temperature."