Mysterious Lakes Under Antarctica May Be Threatened

10 December 2007 | 03:45 Code : 16199 Geoscience events
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An artist's cross-section of Lake Vostok, the largest known subglacial lake in Antarctica....

  An artist's cross-section of LakeVostok, the largest known subglacial lake in Antarctica. Liquid water is thought to take thousands of years to pass through the lake, which is the size of North America's LakeOntario. (Nicolle Rager-Fuller / National Science Foundation) Sometime within the next few months, a Russian device may dip into a place where no man has been before. It won't be on another planet, or even the dark side of the moon. It will be on this planet, in one of Earth's most austere regions, in a place that has not been disturbed in millions of years. A Russian drilling rig has penetrated through more than two miles of Antarctic ice and is within about 70 meters of a huge subglacial lake that may harbor microbial colonies that are unlike anything ever seen on Earth. It's an exciting time for some scientists, and a matter of concern to others. LakeVostok is a huge body of fresh water, about the size of LakeOntario, that is part of a recently discovered network of at least 150 lakes beneath Antarctica's massive ice sheets. The immense pressure of the ice keeps the water in a liquid form. The lakes are fed by subglacial rivers that pump water throughout an astonishing aquatic system, at least a couple of miles below the top of the ice field. The rivers and lakes are now thought to play a key role in regulating the flow of Antarctica's ice sheets toward the ocean. "The water under the ice sheets is what lubricates the glaciers and controls their movement toward the ocean," said oceanographer Mahlon "Chuck" Kennicutt II of TexasA&MUniversity in College Station. Kennicutt is involved in several international programs to explore Antarctica, which, for more than 50 years, has been a model of international cooperation. A team of scientists reported earlier this year that ice above some of the subglacial lakes was moving at a significant pace, at least a couple of meters a day. "It's really ripping along," Helen Fricker, of the Scripps Institution of Oceanography in San Diego, said at the time. The problem is that no one knows enough about those giant subsurface aquifers — which seem to be key players in the movement of the ice — to really evaluate their potential impact on Antarctica's contribution to sea level rise, due to global warming.

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