Antarctic Ice Shelf Fast Collapsing, Scientists Say

A large Antarctic ice shelf in an area that is warming faster than the global average has collapsed with “staggering” rapidity, British scientists said Tuesday.

The shelf designated as Larsen B, 650 feet thick and with a surface area of 1,250 square miles, has collapsed into small icebergs and fragments, the British Antarctic Survey said.

The collapse was first detected on satellite images this month by Ted Scambos of the National Snow and Ice Data Center at the University of Colorado.

“In 1998, BAS predicted the demise of more ice shelves around the Antarctic Peninsula,” said David Vaughan, a glaciologist at the British Antarctic Survey.

“We knew what was left [of Larsen B] would collapse eventually, but the speed of it is staggering. Hard to believe that 500 [quadrillion, or 500,000,000,000,000,000] tons of ice sheet has disintegrated in less than a month,” he said.

In the past 50 years, the Antarctic Peninsula has warmed by 4.5 degrees Fahrenheit, much faster than average global warming, the BAS said. As a result, five ice shelves have retreated. The peninsula is nearest to southern Argentina and Chile.

In January, however, the journal Science reported that new measurements showed the ice in West Antarctica was thickening, reversing earlier estimates that the sheet was melting.