Writing in The Cryosphere http://www.the-cryosphere.net/8/1539/2014/tc-8-1539-2014.pdf, a team of scientists from the Alfred Wegener Institute (AWI) in Germany, have created new digital elevation models of the Greenland and Antarctic ice sheets derived from the European Space Agency’s CryosSat-2 satellite. The results reveal a recent dramatic acceleration of volume loss from the ice sheets.
Between January 2011 and January 2014, the ice sheets lost a combined 507 +/- 107 km3 yr-1 with the Greenland ice sheet contributing approximately 75% of this (~375 km3 yr-1). Comparison of these new models with earlier elevation data for the period 2003-2009 indicate that volume loss from Greenland has increased by a factor of 2.5, while volume loss from West Antarctica has increased by a factor of 3. In Greenland, the new data show a northwards shift in the regions experiencing volume loss, and increased thinning of the ice sheet’s land-terminating margins. The majority of the ice volume loss occurs around the ice sheet margins, either by surface melting and runoff, or by the calving of icebergs directly to the surrounding oceans. Increases in the volume of land ice lost to the oceans will in turn increase global mean sea levels.
Researchers from the University of Sheffield, Department of Geography’s Cryosphere and Climate research group http://www.sheffield.ac.uk/geography/research/groups/climate are actively involved in investigating some of the most important unanswered questions surrounding how the Earth’s great ice sheets might respond to future changes in climate.