A huge Antarctic ice shelf is on the brink of collapse with just a sliver of ice holding it in place, the latest victim of global warming.

"We've come to the Wilkins Ice Shelf to see its final death throes," David Vaughan, a glaciologist at the British Antarctic Survey, said after his plane landed near the narrowest part of the ice.

The flat-topped shelf has an area of thousands of square kilometers, jutting 20 meters out of the sea off the Antarctic Peninsula.

But it is held together only by an ever-thinning 40 kilometer strip of ice that has eroded to an hour-glass shape just 500 meters wide at its narrowest.

In 1950, the strip was almost 100 kilometers wide.

"It really could go at any minute," Vaughan said.

The Wilkins has lost a third of its area but is still about the size of Jamaica or the US state of Connecticut. Once the strip breaks up, the sea is likely to sweep away much of the remaining ice.

Icebergs the shape and size of shopping malls already dot the sea around the shelf as it disintegrates. Seals bask in the southern hemisphere summer sunshine on icebergs by expanses of open water.

A year ago, the Wilkins was said to be "hanging by a thread" after an aerial survey. "Miraculously we've come back a summer later and it's still here. If it was hanging by a thread last year, it's hanging by a filament this year," Vaughan said.

Nine other shelves have receded or collapsed around the Antarctic peninsula in the past 50 years, often abruptly like the Larsen A in 1995 or the Larsen B in 2002.

"This ice shelf and the nine other shelves that we have seen with a similar trajectory are a consequence of warming," Vaughan said.

(Shanghai Daily via Agencies January 21, 2009)