Introduction
Lake Vida is one of the largest lakes in the McMurdo Dry Valley region and is a closed-basin endorheic lake. The permanent surface ice on the lake is the thickest non-glacial ice on earth, reaching a depth of at least 21 metres (69 ft). The ice at depth is saturated with brine that is seven times as saline as seawater. The high salinity allows the brine to remain liquid at an average yearly water temperature of −13 °C (9 °F). The ice cap has sealed the saline brine from external air and water for thousands of years creating a time capsule for ancient DNA. This combination of lake features make Lake Vida a unique lacustrine ecosystem on Earth.
The lake gained widespread recognition in December 2002 when a research team, led by the University of Illinois at Chicago's Peter Doran, announced the discovery of 2,800 year old halophile microbes (primarily filamentous cyanobacteria) preserved in ice layer core samples drilled in 1996. The microbes reanimated upon thawing, grew and reproduced. Due to this discovery and the freezing mechanisms forming Lake Vida's ice-seal, Lake Vida is now noted as a location for research into Earth's climate and life under extreme conditions, specifically the fauna that could have existed on Mars. The unmanned Lake Vida Meteorological Station monitors climate conditions around the lake year round for such scientific study.
A 2010 field campaign, funded by the National Science Foundation through the American Recovery and Reinvestment Act of 2009, to investigate the microbiology and geochemistry of Lake Vida. Led by Peter Doran and Alison Murray from Nevada's Desert Research Institute, the expedition recovered ice cores, brine and sediment samples from the lake using clean drilling procedures to avoid contamination.
The lake itself has no permanent settlements or infrastructure. The nearby Lake Vida Meteorological Station is unmanned, sending meteorological data to McMurdo Dry Valleys Long Term Ecological Research organization. The closest human settlement is Scott Base McMurdo approximately 125 kilometres (78 mi) away. In addition to the unmanned observation station, a 5-day emergency supply of food for 6 people is cached 600 metres (2,000 ft) from the southwestern shore. Research teams establish temporary camps from which research activities are conducted on short term basis in the summer months.
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