Friday, July 27, 2012

Hidden rift valley discovered beneath West Antarctica reveals new insight into accelerating ice loss

British Antarctic Survey: Scientists have discovered a one mile deep rift valley hidden beneath the ice in West Antarctica, which they believe is contributing to ice loss from this part of the continent. Experts from the University of Aberdeen and British Antarctic Survey (BAS) made the discovery below Ferrigno Ice Stream, a region visited only once previously, over fifty years ago, in 1961, and one that is remote even by Antarctic standards.

Their findings, reported in Nature this week reveal that the ice-filled ancient rift basin is connected to the warming ocean which impacts upon contemporary ice flow and loss.

The West Antarctic Ice Sheet is of great scientific interest and societal importance as it is losing ice faster than any other part of Antarctica with some glaciers shrinking by more than one metre per year. Understanding the processes that influence ice loss from West Antarctica is important to improve predictions of its future behaviour in a warming world.

Dr Robert Bingham, a glaciologist working in the University of Aberdeen’s School of Geosciences and lead author of the study, discovered the rift valley whilst undertaking three months of fieldwork with British Antarctic Survey in 2010.

Dr Bingham, whose fieldwork was funded by the UK’s Natural Environment Research Council (NERC) said: “Over the last 20 years we have used satellites to monitor ice losses from Antarctica, and we have witnessed consistent and substantial ice losses from around much of its coastline.

“For some of the glaciers, including Ferrigno Ice Stream, the losses are especially pronounced, and, to understand why, we needed to acquire data about conditions beneath the ice surface.”...

The ice margin of the Ferrigno Ice Stream, where it flows into Eltanin Bay, shot by Rob Bingham, the British Antarctic Survey

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