A NASA program called Operation IceBridge allows for airborne scrutiny of land covered by icesheets, with the purpose of finding what lies beneath.
The suspicion that Greenland's icy cover might hide something beneath was confirmed during research into snow accumulation studies in the south. During the drilling, the ice cores extracted were moist with water, something that immediately indicated the presence of a water reservoir.
Although the temperature at the surface is well below freezing, the water on the ice core was in liquid state, and dripping from the long ice cores.
The large reservoir, measured by IceBridge, was revealed to be 69,930 square kilometers in area. To give an idea as to the size, the reservoir is as big as the state of West Virginia. The water in the aquifer alone could raise sea level by 0.016 inches once the ice sheet melts and the water leeches into the sea.
A similar discovery was made in Antarctica not long ago, where an immense lake, now named Lake Vostok, was found lying under the ice.
The reason why researchers believe that the water does not freeze in the cold winter season, is because Greenland's south is a region of high snow accumulation, which protects the underlying layers from freezing.
In fact temperature strings, strings with sensors that measure temperature at different depths, were able to detect that the water in the aquifer was at 32 degrees Fahrenheit, well above the surface temperature.
Unlike Lake Vostok, the aquifer in Greenland is only 12 meters below the surface. The aquifer is about 25 meters deep.
The scientists believe that this aquifer is generated by the melt which then gets trapped below the surface. In 2012, an unusually warm year, the melt in Iceland was much larger than previous years. But the level of the aquifer is not stable. The water eventually leaves the aquifer and goes into the ocean. The aquifer then refills at the next melt.
Source : NASA/ 1.8.14
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