Recent NASA study claims that ice sheets in Greenland are melting not because of global warming, but because of heat coming from the Earth’s core.
When testing to see how much of the ice sheet is attached to the rock beneath it, the US space agency found something strange- the base of the ice was 10 degrees warmer than the surface.
Basically, the ice sheet is melting from the ground upwards. The heat was actually coming from the bedrock itself and that the ice would melt anyway, global warming or not.
A NASA claimed that : “Greenland’s thick ice sheet insulates the bedrock below from the cold temperatures at the surface, so the bottom of the ice is often tens of degrees warmer than at the top, because the ice bottom is slowly warmed by heat coming from the Earth’s depths.“
He also stated that it very important to know whether the ice sheet is anchored to the bedrock bellow or not, as this influences the movement and flow of the ice in the future.
The NASA spokesman also mentioned that this effect, coupled with the overall warming of the climate, will only accelerate the melting of the ice sheet.
The author of this study is Joe MacGregor, a glaciologist at NASA. He mentioned that while we cannot deny these results, we still need to check how the ice sheets will behave and taking both the results of the study and climate change into account.
The Study, which was published in the Journal of Geophysical Research, consisted of four different approaches to investigate the temperature of the ice sheets base.
The first approach was to examine results of 8 different computer models which were programmed to predict the temperatures at the required location.
After that, they examined the ice sheet itself. They used radar technology place in NASA aircraft.
The third approach was testing the speed of the ice sheets movement. By using satellites, they measured the points in the ice sheet were it moved much faster than it should, suggesting its moving on melted ice.
Finally, they again used satellites, to look for rough surface terrain. This usually indicates that ice has been slowly sliding over certain terrain.
MacGregor and his team concluded, based on the techniques above, that the ice sheets is most likely melting beneath Greenland’s southwester and northeastern ice drainages. It’s also important to mention that for 30 percent of the Greenland ice sheet, there was not enough data to reach a clear conclusion.
MacGregor also states that this is only the first study in fully assessing this problem, and that it „bound to get beat up by other groups as techniques improve“.