Tuesday, June 26, 2012

Expedition Ready to Find Lake Ellsworth - Antarctica's Underground Lake

The Union Jack flies over a field camp at Lake Ellsworth. In the background are the Ellsworth Mountains, the highest range in Antarctica. Photo courtesy: Neil Ross/University of Edinburgh

Could Nessie have a cold-blooded cousin that may have survived the millenia locked in a previously undiscovered, untouched underground lake in Antarctica? Is there any life at all in a frozen, underground lake? Time and science will tell.

After 16 years of meticulous planning, a team of British scientists is finally ready to journey to a remote, windswept plain in Antarctica, where they will drill deep into the ice to take the first-ever samples from a lake cut off from the sunlit world for up to 1 million years.

Their target, Lake Ellsworth, may house tiny organisms utterly new to science, and may proffer the first solid clues regarding the age of the massive ice sheet that covers it.

The lake is 7 mi long, 1 mi wide and about 500' deep (12 km by 3 km by 150 m). It lies in the middle of West Antarctica, hidden beneath nearly 2 mi (3 km) of ice, and scientists plan to use a specially built hot water drill to reach its fresh waters.

A team of a dozen researchers and engineers will assemble at a remote field camp in late November, and drilling is slated to begin in December, said Martin Siegert, the lead investigator for the project and a glaciologist at the University of Bristol.

The massive undertaking is aimed at one simple goal: to fetch 24 small titanium canisters of lake water — just 3.3 ounces (100 milliliters) each — along with sediment from the lake bottom, all scooped up with sterile equipment that will keep both samples and the lake environment utterly pristine.

It will take three straight days of drilling to reach the surface of Lake Ellsworth. Once the lake is breached, Siegert said, the scientists will have about 24 hours to retrieve all the samples before the borehole freezes over again.



However, if the work isn't completed in 24 hours, the team has enough fuel to melt through the ice a second time, which would buy them more time. "Some snags will happen, so you have to build in redundancy," Siegert told OurAmazingPlanet.

The scientists will be able to watch the action live as it unfolds beneath them. The team has affixed tiny, high-definition video cameras to the probe and the sediment corer, along with bright lights to illuminate the darkness. One camera looks up toward the surface, and one looks down.

"We're really looking forward to getting images back," Siegert said.

Although the canisters of lake water won't be opened until they are returned to clean rooms back in England for analysis, the world won't have to wait to learn what life forms — if any — lurk in Lake Ellsworth.

As the water is sucked into the titanium canisters, it will be pushed through a filter — a mesh so fine that, if any microbes are indeed living in the frigid, pitch-dark lake, some will end up caught on the filter.

"So when the probe comes to the surface, we won't be able to analyze the water, but we will be able to analyze the filter immediately," Siegert said. "We will look at it under a microscope within a few hours. So the question, 'Is there life in the lake?,' we will have an answer very quickly."

Yet that is not the only question scientists are seeking to answer. Scientists are hoping that the layers of sediment plucked from the bottom of Lake Ellsworth will offer clues to the true age of the West Antarctic Ice Sheet.

"We don't know. It could be 100,000 to 1 million years old," Siegert said. "We think it's at risk of change, but what we need is to understand how likely that is, and gain an appreciation of when the ice sheet last decayed because of environmental conditions," he said.

If all goes according to plan, scientists could have samples of the ancient lake in hand by Dec. 18, 2012.

It's likely the British will be the first of three groups currently seeking to sample a long-buried Antarctic lake.

Earlier this year, after more than a decade of drilling, a Russian team in East Antarctica finally breached Lake Vostok, the largest hidden lake on the continent.

The approach of the brutal winter season, along with the nature of the drill equipment, prevented the Russian team from bringing back samples; however, many scientists question the integrity of any water retrieved from Lake Vostok. The Russian team has used kerosene and other materials to keep the borehole open, and there are fears of sample contamination.

In early 2013, an American team is planning to drill to hidden lakes in West Antarctica.

Siegert said his team is finally feeling relaxed after years of furious work, and said he can't speculate what they'll find in Lake Ellsworth.

"Honestly, we just don't know until we do it," he said. "That's one of the wonderful things about this project. We're very excited about doing our work."

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