Permanent Human Settlement of the Earth, Space and Ocean Frontiers

Friday, March 31, 2006

The Lake That Time Forgot

RADARSAT image of Lake Vostok

Ralph Buttigieg

Sydney, NSW , Australia

In a remote region of planet Earth there exists a huge freshwater lake that no human has ever seen. This is Lake Vostok in Antarctica. The lake is hidden from our eyes by a 4000 meter thick cover of solid ice that has isolated the water for a million years or more. Named after the nearby Russian base Vostok, its existence was confirmed in the 1990's through radar imagery and spaceborne radar altimetry. This is no small body of water either, with a surface area of 14000 square kilometers the lake is about as large a Lake Ontario. The water's depth varies from 200 to 800 meters and the total water volume is estimated to be 5,400 cubic kilometers. The reason it has not frozen over is because the Earth's internal heating warms the bottom and the ice acts like an insulator. Even so the water is a bitterly cold -3 deg C.

The water is unlike anything found in a surface lake. Over the centuries air bubbles from the ice above have been released into the water giving the water 50 times the normal oxygen level. If the ice was removed the water would bubble and fizz like a shaken coke bottle.

The great question is what, if any, form of life exists in that water? NASA is very interested as they see Lake Vostok as an analog for what may be in the oceans of the Solar System ice worlds such as Enceladus and Europa. NASA scientists claim to have already found microorganisms in the ice above the lake so are excited of what may be found in the cold water beneath. The big concern is contamination. There is already controversy of the microorganism findings some scientists claim the bugs are contaminants .

They claim the lake is too toxic for life to exist and is sterile. The American scientists respond that their decontamination procedures are effective and any life would evolve to adapt to high oxygen concentrations.

We will know the truth soon enough as the Russians are drilling through the ice to the lake water. They stopped in March this year, 130 meters from the water's surface and will resume in December, the beginning of summer. Environmentalists fear the pristine environment will be contaminated by the drilling but the Russians are determined to continue. They hope to crack through the ice by 2008.

This is another of those “lost worlds” that I have written about and the possibility of life down there is just fascinating. (“Lost World” defined as the still undiscovered environments on Earth with unique ecologies.) What could evolution have produced after a million years in such an extreme environment? There is minimal energy down there and the lake has been cut off from the rest of Earth's biosphere. Could there be more advanced life forms than microorganisms? As one researcher said:

If the lake does contain life, "it would not be an overstatement to say it could be one of the biological finds of the millennium," said USC Dean of Research Donal T. Manahan, a biologist who is chairman of the polar research board of the National Academy of Sciences

The opportunity to sample such an ancient, untouched habitat, Manahan said, "comes once in a million years."

I'm sure going to be watching developments.

For more information see here, here and here.