Greenland's ice sheet do not contribute towards rising sea-level

Washington, Apr 20 (UNI) Melting water from ice sheets are of major concern to climate scientists as it could lead to a rise in sea levels, but draining of water from the top of Greenland's ice sheet do not seem to contribute towards it, a new research says.

Scientists from the Woods Hole Oceanographic Institution (WHOI) said Greenland's summer lakes, which can drain away as fast as Niagara Falls, did not seem to accelerate the movement of the ice sheet into the ocean as previously thought.

Thousands of lakes form on top of Greenland's glaciers every summer due to the increased sunlight and warm air. Initially, experts believed that the melting water might make its way to the base of the ice and lubricate the Greenland ice sheet's passage into the sea, which would contribute to a global sea-level rise.

However, the new study, published in the online journal Science has cast doubts on that theory. Led by glaciologists Sarah Das and Ian Joughin, the study monitored the evolution of surface lakes on Greenland in the summers of 2006 nd 2007, and tracked the progress of glaciers moving toward the coast.

It was found that the surface meltwater was responsible for only a few per cent of the movement of the glacier that they monitored.

''The new findings indicate that while surface melt plays a substantial role in ice sheet dynamics, it may not produce large instabilities leading to sea level rise,'' the scientists said, adding there were still other mechanisms that were contributing to the current ice loss which is likely to increase as climate warms.

It is hard to envision how a trickle or a pool of meltwater from the surface could cut through thick, cold ice all the way to the bed, they said.

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