IPY 2007-2008

Introduction

The Antarctic Peninsula is one of the world’s regions that is most affected by global warming with an increase of atmospheric temperature well above the global average. The collapse of various ice shelves is attributed to this phenomenon: Wordie Ice Shelf around 1989, Larsen A in 1995, Larsen B in 2002 and more recently the disintegration of Wilkins Ice Shelf, one of the southernmost ice shelves at the Peninsula (ESA news, 10 July 2008). Between February and July 2008 it lost almost 2000 km² in a series of break-up events that even continued up to the following year, confirming the serious consequences that climate change causes for the world’s glaciers.
 
The disintegration events themselves do not contribute t sea level rise as the ice was already floating before. However, the glaciers that drain into the ice shelves lose their buttressing causing acceleration and thinning that produces larger ice discharges and hence a contribution to sea level rise.
 
This process has been observed in distinct geographic areas particularly in the north of the Antarctic Peninsula as well as in Greenland, where glaciers respond with an outstanding acceleration on the absence of ice shelves. However, this behaviour is extending to the south. For instance, Larsen C although still not retreating is experimenting a thinning trend. Given the bedrock topography in this area, a collapse of Larsen C could potentially result in the formation of channels and an archipelago separating the Peninsula from the continent.

To the southwest of Larsen C, the glaciers draining into Wordie Bay experienced acceleration and thinning after the collapse of Wordie Ice Shelf.