25 Oct 2012:
Rapid Thinning of Glaciers
Seen After Collapse of Antarctic Ice Shelf
NASA has released satellite photos that vividly depict the precipitous thinning and retreat of two Antarctic glaciers
following the disintegration of the Larsen B Ice Shelf. That ice shelf — which floated
on top of the Weddell Sea and once was the size of Connecticut — collapsed in 2002 after several years of warm summer temperatures. The Larsen B had acted as a buttress slowing the flow of numerous glaciers into the sea. The NASA satellite images, taken in 2002 and in 2012, demonsrate how swiftly the Green and Hektoria glaciers behind the ice shelf surged into the ocean. The 2002 photo shows the glaciers covering much of nearby mountain ridges and the termini, or end points, of the glaciers are not visible. The 2012 photo shows that the thinning glaciers now cover considerably less of surrounding mountain ridges and the termini of both glaciers are visible. The 2012 image also shows the numerous crevasses that have formed as the glaciers have thinned. A third NASA photo depicts how the lower reaches of the glaciers, seen in red, have lost as much as 720 feet of vertical thickness in 10 years. The two glaciers’ recent loss of 5.6 billion tons of ice per year is contributing to global sea level rise.