Greenland Ice Sheet Starting to Thaw, NASA Maps Areas Affected by Warm Climate

Researchers from NASA have officially released a map showing the thawed areas of the Greenland Ice Sheet. Not only do these images prove the effect of climate change, NASA's findings would also help predict how the ice sheet would react to global warming.

The study on Greenland's ice sheet was published in the Journal of Geophysical Research - Earth Surface. This study was led by NASA glaciologist of Goddard Space Flight Center in Greenbelt, Maryland, Joe MacGregor. Joining him was researcher for NASAs Jet Propulsion Laboratory in Pasadena, Calif. Helene Seroussi.

"We're ultimately interested in understanding how the ice sheet flows and how it will behave in the future," said MacGregor. "If the ice at its bottom is at the melting-point temperature, or thawed, then there could be enough liquid water there for the ice to flow faster and affect how quickly it responds to climate change."

NASA researchers combined four different approaches in investigating Greenland's ice sheet. First, results from eight computer models of the sheet were examined. Second, layers of what composed the ice sheet were studied. The layers were detected by the radar on NASAs Operation IceBridge aircraft. It was this radar that suggested the bottom part of the ice sheet was melting at alarming rates.

Third, researchers looked at ice surface "speed limit" which was measured by satellites. "Speed limit" refers to the maximum velocity wherein ice could flow but still be frozen to the rock. Fourth, images from the Moderate Resolution Imaging Spectroradiometers taken from NASA Terra and Aqua satellites were studied. The images would indicate ice sliding over the thawed areas.

"Each of these methods has strengths and weaknesses. Considering just one isn't enough. By combining them, we produced the first large-scale assessment of Greenland's basal thermal state," explained MacGregor.

Based on the data accumulated, MacGregor along with his team concluded that the Greenland ice sheet is indeed thawed, particularly in the northeastern and southeastern ice drainage. For now, the NASA team is refining the map to predict the movement of Greenland's ice sheet in the years to come.