Map of melting in Greenland published by NASA. Credit: NASA/Earth Observatory.

NASA is reporting of new data about the melting in Greenland in 2007. In short: areas at high altitudes (over 1.2 miles above sea level) are experiencing record melting, clocking in at a chilling 150% above average. At lower altitudes, the melting is 30% above average. To put this in perspective, the amount of snow that has melted this year over Greenland could cover the U.S. more than twice over.

The melting data came from satellite-based microwave imagery, which was then compared to the average snow melting from 1988-2006. The map on the left shows the melting difference between the past 19 years and this year: the redder it is, the more melting that occured in that area this year. All in all, this puts 2007 as the fifth highest in amount of melting. The top four are, in order: 2005, 2002, 1998 and 2004.

Needless to say, this is scary proof that global warming is really happening and that predicting and modelling how melting occurs is very difficult. And then we have to think about where this melted snow is going, i.e., to the seas, which brings up the thorny issue of rising sea levels. The image above is no longer pretty, is it?