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Antarctic lakes

From Citizendium - Reading time: 4 min

There are hundreds of antarctic lakes, in Antarctica.[1][2][3][4][5][6][7] In 2018 researchers at the Alfred Wegener Institute's Helmholtz Centre for Polar and Marine Research published a study they claimed cast doubt on earlier estimate that there were almost 400 subglacial antarctic lakes.[8] Antarctica also has some relatively small regions that are clear of ice and snow, and there are some surface lakes in these regions. They called for on the ground seismic studies, or drilling, to determine a more reliable number.

These lakes are buried beneath deep layers of glacial ice.[1][2][3] When a glacier is very thick, the pressure at the bottom is great enough that liquid water can exist at temperatures where water would freeze, at regular pressures. The ice above Lake Vostok, the largest antarctic lake, is approximately 4 kilometres thick.

Scientists studying the lakes, by careful drilling and water sampling, suggest conditions there may resemble the oceans believed to exist on planet Jupiter's moon Europa.[2][3]

Selected Antarctic lakes[edit]

Selected Antarctic lakes
name surface
area		 depth volume below
surface		 notes
Ablation Lake 117 m (383.86 ft)+ 500 m (1640.42 ft)
  • The lake contains both saline and freshwater layers.[9][10]
Algae Lake
Amphitheatre Lake
  • A surface lake.
Beaver Lake
  • A surface lake, near a "stagnant" glacier, its name derives from the STOL Beaver aircraft used to supply a nearby base, not from the presence of actual beavers.
Lake Boeckella
  • A surface lake, named for the crustaceans from the genus Boeckella it hosts.
Lake Burton 1.35 km^2 9,690,000 cubic metres
  • a meromictic and saline lagoon
Changing Lake
Concordia Lake 900 km^2 4 km (2.49 mi)
  • A large subglacial lake, discovered in 1999.[11]
  • In 2009 it was the second largest subglacial lake to be studied.[12]
Lake Ellsworth
Forlidas Pond
  • This small pond is the only pond in the northern Pensacola Mountains.[13]
Lake Whillans 60 km^2 800 metres
  • Located near the edge of the Ross Ice Shelf.[14]
  • A 2022 study found a vast reservoir of ground water under the lake.[14]

References[edit]

  1. ↑ 1.0 1.1 Appeal to the Duma on Lake Vostok, Antarctica (PDF). Antarctic and Southern Ocean Coalition (14 April 2008). Retrieved on 10 February 2011.
  2. ↑ 2.0 2.1 2.2 Quirin Schiermeier. Teams set for first taste of Antarctic lakes, Nature (journal), 2010-03-23. Retrieved on 2018-12-06. “Over the past 40 years, radar imagery has revealed around 150 freshwater lakes of various sizes and ages beneath the massive Antarctic ice sheet. Some have been isolated from the outside world for millions of years, raising the possibility that they hold unique life forms. The dark, nutrient-deprived environment of the lakes could resemble conditions on Jupiter's moon Europa, which is assumed to hold a large ocean beneath its frozen surface.”
  3. ↑ 3.0 3.1 3.2 Peter Aldhous. First samples of Antarctic lake reveal thriving life, New Scientist magazine, 2014-08-20. Retrieved on 2018-12-06. “Antarctica is home to about 400 subglacial lakes, many of which are linked in drainage basins. Priscu calls it 'the planet’s largest wetland'.”
  4. ↑ Lakes Drain under Antarctic Ice Sheet, NASA. Retrieved on 2018-12-06.
  5. ↑ Bethan Davies. Glacier hydrology, Antarctic Glaciers, 2018-06-11. Retrieved on 2018-12-06. “Beneath the Antarctic Ice Sheet, these subglacial drainage channels are connected to numerous subglacial lakes.”
  6. ↑ Becky Oskin. Cold, Dark and Alive! Life Discovered in Buried Antarctic Lake, Livescience magazine, 2014-08-20. Retrieved on 2018-12-06. “Nearly 4,000 species of microbes inhabit Lake Whillans, which lies beneath 2,625 feet (800 meters) of ice in West Antarctica, researchers report today (Aug. 20) in the journal Nature. These are the first organisms ever retrieved from a subglacial Antarctic lake.”
  7. ↑ Benjamin E. Smith, Helen A. Fricker, Ian R. Joughin, Slawek Tulaczyk. An inventory of active subglacial lakes in Antarctica detected by ICESat (2003–2008), Journal of Glaciology, 2009. Retrieved on 2018-12-08.
  8. ↑ Far fewer lakes below the East Antarctic Ice Sheet than previously believed, Science Daily magazine, 2018-11-07. Retrieved on 2018-12-06. “Thanks to our data, we can now fill in some of the blank spots on the map of Antarctica." However, when it comes to large lakes -- they had expected to find ones as large as Lake Constance -- the scientists came up empty-handed, even though they analysed the radar data for every known lake criterion.”
  9. ↑ R.B. Heywood (1977-05-26). "A Limnological survey of the Ablation Point area, Alexander Island, Antarctica". Retrieved on 2018-12-06. “Two of the lakes are unusual in that they are in contact with seawater from George VI Sound which is covered by an ice shelf, 100-500 m thick, and which separates Alexander Island from the Antarctic mainland.”
  10. ↑ Antarctica Detail: Ablation Lake, US Geographic Service. Retrieved on 2018-12-06. “A pro-glacial tidal lake in Ablation Valley, Alexander Island, with stratified saline and fresh water and depths exceeding 117 meters. The feature is dammed in the upper portion by ice that pushes into the lake from the adjacent George VI Ice Shelf. Named after the valley following British Antarctic Survey (BAS) limnological research from 1973.”
  11. ↑ Antarctica Detail: Concordia Subglacial Lake, US Geographic Service. Retrieved on 2018-12-06. “First located in Dec. 1999. The name derives from the nearby Italian Concordia research station.”
  12. ↑ Malte Thoma, Klaus Grosfeld, Irina Filina, Christoph Mayer. [https://www.sciencedirect.com/science/article/pii/S0012821X0900380X Modelling flow and accreted ice in subglacial Lake Concordia, Antarctica Author links open overlay panelb Show more https://doi.org/10.1016/j.epsl.2009.06.037], Science Direct magazine, 2009-08-30. Retrieved on 2018-12-06. “This paper focuses on Lake Concordia — the second largest subglacial lake in Antarctica over which substantial geophysical data has been collected. This lake is covered by about 4000 m ice and is located near Dome C.”
  13. ↑ Antarctica Detail: Forlidas Pond, US Geographic Service. Retrieved on 2018-12-06. “The only pond in the northern Pensacola Mountains, it is of much interest to biologists.”
  14. ↑ 14.0 14.1 Gregory Barber. A Vast Underground Water System Helps Drive Antarctica’s Glaciers, Wired magazine, 2022-05-05. Retrieved on 2022-05-06. “In a study published in the journal Science, Gustafson’s team offers a long-awaited schematic of the watery world underneath the ice. A vast reservoir of groundwater reaches more than a kilometer below subglacial water features like Lake Whillans, containing 10 times as much water.”
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