Ice Shelf Collapse

A massive chunk of Antarctica's Wilkins Ice Shelf has collapsed into the ocean.

The collapse of a substantial section of the shelf was triggered February 28 when an iceberg measuring 41 by 2.4 kilometers (25.5 by 1.5 miles) broke off its southwestern front.

That movement led to disintegration of the shelf's interior, of which 414 square kilometers (160 square miles) have already disappeared, scientists say.

The Wilkins Ice Shelf is a broad plate of permanent floating ice 1,609 kilometers (1,000 miles) south of South America, on the southwest Antarctic Peninsula.

Now, as a result of recent losses, a large part of the 12,950-square-kilometer (5,000-square-mile) shelf is supported by a narrow 5.6-kilometer (3.5-mile) strip of ice between two islands, scientists said.

"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," NSIDC lead scientist Ted Scambos said in a statement.

The chunk that collapsed was about seven times the size of Manhattan. Even though it was so large, it will not affect sea levels because the ice shelf was already floating on the water. However, it portends further disintegration of ice on the Antarctic Peninsula, whose temperature is rising 0.9°F per year. Here are some photos of the ice shelf collapse, captured by a satellite.