Buried beneath several miles of ice in Antarctica are lakes ranging in size from Lake Ontario to lakes the size of Manhattan. Lake Vostok, the largest subglacial lake on Earth, is believed to harbor ancient life that has been isolated from open exchange with the atmosphere for several million years.
Lake Vostok (left) , discovered in 1996 by Russian and British scientists underneath the Russian station Vostok in Antarctica, is one of 140 subglacial lakes located beneath the Antarctic ice-sheet. At 250km long and 50km wide, some 4000 meters underneath the surface ice, and could be one of the most important scientific finds of the last several decades.
No other natural lake environment on Earth has this much oxygen as Lake Vostok -an oligotrophic extreme environment, one that is supersaturated with oxygen, with oxygen levels 50 times higher than those typically found in ordinary freshwater lakes. The sheer weight of the continental icecap sitting on top of Lake Vostok is believed to contribute to the high oxygen concentration. Microbial organisms in Lake Vostok must be capable of overcoming very high oxygen stress, and may have had to evolve special adaptations, such as high concentrations of protective enzymes, in order to survive.
The discovery of interconnected lakes beneath kilometers of ice in Antarctica could be one of the most important scientific finds in recent years, but proper procedures need to be established before investigation begins, says Mahlon "Chuck" Kennicutt II, professor of oceanography at Texas A&M University and a leader in the research efforts.
The National Science Foundation and 11 countries involved in the research and exploration are seeking agreement on how best to study these unique environments, which include at least 145 lakes under Antarctica's massive ice sheets.
Participants in the project known as The Russian Antarctic Expedition have announced their intentions to penetrate Lake Vostok during coming Antarctic field seasons.
"These lakes were rediscovered within the past 10 years or so, but no one yet has penetrated them and we want to make sure that the research is done properly and adheres to the highest environmental stewardship principles," says Kennicutt.
"This has the potential to be one of the most important scientific discoveries in years, since sub-ice water appears to be an important player in many different processes fundamental to Antarctica and our planet.
"We believe that these lakes are part of an interconnected system that spans the entire Antarctic continent," he adds. "These bodies of water are several miles beneath the ice sheet which took millions of years to form, meaning these lakes have been undisturbed and disconnected from our atmosphere for hundreds of thousands of years. It is highly likely that unique microbial communities that we never knew existed are lake residents."
Scientists from the countries involved, which include the U.S., France, Italy, Japan, Russia, the United Kingdom and others, have concluded that lake entry and sampling will ultimately be necessary to accomplish the ambitious research objectives.
"How to do this in the best way to preserve these environments and to be least invasive is a key question that needs further discussion," Kennicutt notes.
"The countries involved have all agreed we must do as much as possible to avoid altering the lakes or causing any environmental damage."
Research in Antarctica has always had a special set of rules among nations. It is the only continent on Earth that is managed through an international treaty signed by 45 countries representing two-thirds of the world's population. By unanimous consent of these nations, Antarctica has been viewed as a continent for science, research and peace.
Scientists believe that the lakes exert an important control over the large ice-sheet movement, and that they exist as above-ground waterways do, with streams, rivers and lakes commonplace. Believed to span underneath the entirety of the continent that is 98% ice, they represent the chance to look back several million years. With millions of years separating them from our current atmosphere, Kennicutt believes that “…It is highly likely that unique microbial communities that we never knew existed are lake residents.”
And while it is thought that it could take the US some 3-5 years to begin work itself on researching and studying the lakes, Kennicutt states that “…Once the U.S. becomes fully engaged in these research efforts, this will almost certainly be one of the dominant Antarctic research focus areas for at least the next decade, if not longer.”
Posted by Josh Hill and Casey Kazan.
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