A piece of the Antarctic ice shelf the size of Delaware has shattered and separated from the continent in the largest such event in 30 years. The Larsen B shelf on the eastern side of the Antarctic Peninsula has fragmented into small icebergs.
Researchers predicted in 1998 that several ice shelves around the peninsula were doomed because of rising temperatures in the region, but the speed with which the Larsen B has gone has shocked them. ?We knew what was left would collapse eventually, but the speed of it is staggering,? says Dr. David Vaughan, a glaciologist at Cambridge in the U.K. ?[It is hard] to believe that 500 million billion tons of ice sheet has disintegrated in less than a month.?
The Larsen B was one of five ice shelves — huge masses of ice that are floating extensions of the ice sheets covering the land — that had been steadily shrinking because of climate change, Vaughan says. But the break up of the ice mass will not raise sea levels because the ice was already floating. Sea levels will only be affected if the land ice behind it now begins to flow more rapidly into the sea.
A total of about 1,250 square miles of ice shelf has disintegrated in a 35-day period beginning on Jan. 31st. Since 1974 the ice shelf in the Antarctic Peninsula has been reduced by about 5,200 square miles. Over the last five years, the Larsen B shelf has lost a total of 2,200 square miles and is now about 40 percent of the size necessary for its stability. The shattered ice has left a trail of thousands of icebergs in the Weddell Sea, east of the Antarctic Peninsula. Scientists first learned of the Larsen B collapse from images sent by the NASA?s Modis satellite. Scientists hope to gather data from the site will help them determine when such an event last happened and which ice shelves are threatened in future. ?This breakup gave us the information we need to reassess the stability of ice shelves around the rest of the Antarctic continent,? says U.S. glaciologist Ted Scambos. ?They are closer to the limit than we thought.?
The U.S. National Snow and Ice Data Center (NSIDC) says, ?This is the largest single event in a series of retreats by ice shelves in the peninsula over the last 30 years. The retreats are attributed to a strong climate warming in the region.?
Scientists worldwide have monitored the Larsen B shelf since November 2001, when a researcher at the Instituto Ant
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