Reply #23: West Antarctic Glaciers Melting At 20 Times Former Rate, Rock Analysis Shows

[jpak]

http://www.sciencedaily.com/releases/2008/02/080229075228.htm

Boulders the size footballs could help scientists predict the West Antarctic Ice Sheet's (WAIS) contribution to sea-level rise according to new research.

Scientists from British Antarctic Survey (BAS), Durham University and Germany's Alfred Wegener Institute for Polar and Marine Research (AWI) collected boulders deposited by three glaciers in the Amundsen Sea Embayment -- a region currently the focus of intense international scientific attention because it is changing faster than anywhere else on the WAIS and it has the potential to raise sea-level by around 1.5 metres.

Analysis of the boulders has enabled the scientists to start constructing a long-term picture of glacier behaviour in the region. An urgent task is to put recent ice sheet changes into a historical context, and determine if these are part of a natural retreat since the end of the last glacial period (about 20 thousands years ago), or if they are a result of recent human-induced climate change.

Lead author Dr Joanne Johnson of BAS says, "Until now we didn't know much about the long-term history of this part of the West Antarctic Ice Sheet because the region is incredibly remote and inaccessible. Our geological findings add a new piece to the jigsaw and will be used for improving computer models -- the most important tools we have for predicting future change."

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