Antarctic ice shelf 'hangs by a thread'

Washington, March 26 : Satellite and video images captured by the British Antarctic Survey (BAS) has revealed an Antarctic ice shelf that looks set to be the latest to break out from the Antarctic Peninsula, supported only by a thin strip of ice hanging between two islands.

The huge (41 by 2.5 km) km2 ice berg was spotted by scientists monitoring satellite images of the Wilkins Ice Shelf. They discovered that the iceberg seems to have broken away in recent times, and is still on the move.

The Wilkins Ice Shelf is a broad sheet of permanent floating ice on the southwest Antarctic Peninsula roughly 1,000 miles south of South America.

Glaciologist Ted Scambos from the University of Colorado then alerted colleagues Professor David Vaughan and Andrew Fleming of the BAS that the ice shelf looked at risk. After checking daily satellite pictures, BAS sent a Twin Otter aircraft on a reconnaissance mission to check out the extent of the breakout.

"Wilkins is the largest ice shelf on the Antarctic Peninsula yet to be threatened. I didn't expect to see things happen this quickly," said Professor Vaughan.

"The ice shelf is hanging by a thread - we'll know in the next few days or weeks what its fate will be," he added.

"While the area of collapse involves 160 square miles at present, a large part of the 5,000-square-mile Wilkins Ice Shelf is now supported only by a narrow strip of ice between two islands," said CU-Boulder's Ted Scambos.

"If there is a little bit more retreat, this last 'ice buttress' could collapse and we'd likely lose about half the total ice shelf area in the next few years," he added.

According to Professor Vaughan, climate warming in the Antarctic Peninsula has pushed the limit of viability for ice shelves further south - setting some of them that used to be stable on a course of retreat and eventual loss.

"The Wilkins breakout won't have any effect on sea-level because it is floating already, but it is another indication of the impact that climate change is having on the region." said Ted Scambos of the University of Colorado.

"We believe the Wilkins has been in place for at least a few hundred years. But warm air and exposure to ocean waves are causing a break-up," he added.

ANI