Parts of Greenland’s ice sheet melting fastParts of the Greenland ice sheet are melting at up to nearly 42 centimeters (cms) per year, and the thinning is affecting ice at higher altitudes than expected, according to a study published this week in the journal Nature.
Knowledge of the state of the Greenlandic and Antarctic ice sheets is important for predicting sea level changes around the globe. Modern techniques using satellites provide short-term data, but little information on long-term changes.
Canadian glaciologist W S B Paterson and Danish scientist Niels Reeh of Denmark’s Technical University compared recent satellite measurements with those made by British explorers who trekked across northern Greenland between 1953–54.
Back then, the British North Greenland Expedition used trigonometry to calculate elevation as they traversed the ice sheet. Paterson and Reeh compared this data with radar measurements made by satellite in 1995 to find out if the thickness of the ice sheet has changed over the decades.
They found that the eastern side of the ice sheet has remained stable or even thickened slightly at rates up to 9.7cms per year.
"On the west side, however, the thinning rates of the ice sheet are significantly higher and thinning extends to higher elevations than had been anticipated from previous studies," write Paterson and Reeh. In the worst section, the estimated thinning was between 20.3 and 41.7cms per year.
The study could be a valuable contribution to understanding feedbacks from changes in the Arctic to the global climate system. For instance, the melting of glaciers and sea ice is expected to cause a global rise in sea level, and affect patterns of ocean currents by lowering the density of seawater through dilution.
For further information contact:
Lynn Rosentrater, Climate Change Officer, WWF Arctic Programme, tel: +47 22 03 65 02, mob: +47 99 15 76 64, email: firstname.lastname@example.org