April 6, 2009

Ice Bridge Ruptures In Antarctic

An ice bridge in the Antarctic, which linked a shelf of ice the size of Jamaica to two islands, has collapsed.

According to scientists, the rupture provides further evidence that climate change is occurring in the region.

Researchers also fear that the Wilkins Ice Shelf, located on the western side of the Antarctic Peninsula, could be on the brink of breaking away.

The bridge was regarded by scientists as an important barrier holding the shelf structure in place.

The removal of the bridge will allow ice to move freely between Latady and Charcot islands, into the ocean.

Satellite pictures provided by the European Space Agency last week showed that the 25 mile long strip of ice had splintered at its narrowest point.  Newly created icebergs could also be seen on the western side of the peninsula.

According to Professor David Vaughan, a glaciologist with the British Antarctic Survey, the breaking of the bridge had been expected for some weeks.

"We know that [the Wilkins Ice Shelf] has been completely or very stable since the 1930s and then it started to retreat in the late 1990s; but we suspect that it's been stable for a very much longer period than that," he told BBC News.

"The fact that it's retreating and now has lost connection with one of its islands is really a strong indication that the warming on the Antarctic is having an effect on yet another ice shelf."

"Charcot Island will be a real island for the first time in history," Vaughan said.

The break-up is heightening concern over the impact of climate change in the Arctic.

"My feeling is that we will lose more of the ice, but there will be a remnant to the south," said Vaughan.

"We believe the warming on the Antarctic Peninsula is related to global climate change, though the links are not entirely clear," he added.

The peninsula has been one of the fastest warming regions on the planet over the last 50 years.

Nine other shelves have receded or collapsed around the Antarctic Peninsula during this period. 

According to research, when the ice shelves collapse, glaciers can start moving toward the ocean more rapidly, leading to an increase in sea levels.

How much the sea levels will rise is still being debated by scientists.

These accelerated effects were not included in sea level projections made by the UN's Intergovernmental Panel on Climate Change in 2007. 


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