Greenland’s Ice Feels the Heat in Record-Setting 2010
Greenland’s massive ice sheet experienced record surface melting and runoff last year, according to research released today.
Unusually warm conditions in much of the country helped extend the annual melting season by up to 50 days longer in 2010 than the average observed between 1979 and 2009, researchers found.
Last year also set records for the amount of water runoff from the ice surface, loss of surface ice and the number of days when ice was bare rather than blanketed by snow. Summer snowfall was below average.
“In 2010, generally speaking, surface temperatures were higher than average,” said lead author Marco Tedesco of the City College of New York’s Cryosphere Processes Laboratory. “It was not just the summer temperatures, but also the spring and later winter temperatures. The melting season started early and lasted much longer than normal.”
Here is the abstract from the published science paper - [PDF link]:
Analyses of remote sensing data, surface observations and output from a regional atmosphere model point to new records in 2010 for surface melt and albedo, runoff, the number of days when bare ice is exposed and surface mass balance of the Greenland ice sheet, especially over its west and southwest regions. Early melt onset in spring, triggered by above-normal near-surface air temperatures, contributed to accelerated snowpack metamorphism and premature bare ice exposure, rapidly reducing the surface albedo. Warm conditions persisted through summer, with the positive albedo feedback mechanism being a major contributor to large negative surface mass balance anomalies. Summer snowfall was below average. This helped to maintain low albedo through the 2010 melting season, which also lasted longer than usual.
So, it is a combination of phenomena that are adding up to the increased melting of the icecap.
Some of the researchers are associated with a blog which they update regularly: Cryospheric Processes Laboratory
They have also made a video of recent photos and short video clips from their visits to Greenland:
It will take very many years for the ice sheet over Greenland to melt completely, but it is melting.