Tuesday, October 11, 2011

Antarctica's ancient lake may yield clues over Earth's future

The Guardian (UK) via Reuters: An ancient lake hidden deep beneath the west Antarctic ice sheet may reveal vital clues about climate change, future sea level rises and uncover new forms of life, according to a group of British engineers and scientists. This month, a British engineering team will travel to one of the most remote and hostile environments on Earth – Lake Ellsworth, which is buried under two miles (3km) of ice – in the first stage of a project costing over £7m.

The ice sheet covering the lake has trapped the Earth's geothermal heat, preventing it from freezing. The team will prepare for a challenging drilling operation starting next November to collect water and sediment samples from the lake's floor, which will help scientists assess the stability of the west Antarctic ice sheet and future sea level rises.

"If we can find out if or when the ice sheet retreated or collapsed, it could tell us what kind of conditions would lead to a west Antarctic retreat in the future," Mike Bentley, a glacial geologist at Durham University, told reporters at a briefing on Monday.

For many years, scientists have speculated that new and unique forms of microbial life evolved in this dark, sterile and isolated environment, which experiences temperatures of -25C (-13F). The team expects to find evidence of viruses, bacteria, single-celled microorganisms called archea and complex cell organisms called eukaryotes. These lifeforms could increase our understanding of how life on Earth began and evolved and help define its limits.

"Finding life in a lake that could have been isolated from the rest of the biosphere for up to half a million years will tell us so much about the potential origin of and constraints for life on Earth and may provide clues to the evolution of life on other extraterrestrial environments," said David Pearce, science coordinator at the British Antarctic Survey. "If we find nothing (it) will be even more significant because it will define limits at which life can no longer exist on the planet."...

A sight in Marie Byrd Land, West Antarctica, shot by BrucePL (Bruce Luyendyk), Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

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