german largest surface freshwater lake interior central queen land east antarctica situated kilometres southwest oasis lake approximately kilometres long kilometres wide surface area square kilometres maximum depth metres lake permanently covered ice partly bounded ice unusual lake dissolved oxygen percent low primary production water column despite high oxygen lake small sub basin southern end sediments higher concentration known lake earth primary production communities grow floor lake water temperature varies ice cover lake metres thick ice cover persisted years scientists studying climate change fear significant environmental changes associated global warming coming decades past water chemistry lake compared chemical activity addition higher measures high concentrations geography lies interior central queen land east antarctica roughly northern coast situated kilometres southwest oasis lake approximately kilometres long kilometres wide surface area square kilometres square kilometres reported maximum depth metres permanently covered ice average thickness metres summer lake main source water lake outlet water lost ice cover lake categorized ultra lake history studies established lake long permanent ice cover studies carried summer confirm lake characteristics thermal convection reason given nature process underwater melting adjacent ice stated lake existed period emerged melt water pond studies revealed number large dam lake studies carried summer seasons indicated annual rate metres residence time estimated years floating metres diameter evolved result debris deposits pro glacial interaction mass hills surrounding lake displacement glacial ice lake ice lake discovered expeditions studied lake characteristics reconnaissance study lake carried early followed studies russian german scientists research studies carried prior physical chemical parameters lake water stated mixed studies performed summer found significant metre wide trough southeastern lake metres deep sharp vertical temperature dissolved oxygen electrical recorded depth metres metres followed metres extending metres lake metres water column hydrogen presence hydrogen associated decreased concentrations indicating probably arose reduction salt content upper levels lake times glacial melt water increased metres concentration doubling lake highly depth metres depth drops reaching slightly acidic value maximum depth proportion sediment lake highest recorded lake world according nasa scientists discovered conical growing largest living ones known date small present appears large conical small different communities communities provide important analog oldest fossil found date expeditions november december headed nasa lake test bed hunt extreme life conditions lake similar respects thought exist planets contain water ice lake provide analog environments exist space expedition find new strains lake waters including hydrogen expedition involved international team scientists teachers explored oasis aspects expedition objectives test laser induced exploration mars poles monitor global climate change evaluate methods detecting contamination subsequent fragile endangered ecosystem results indicate permanently ice covered region little usable soil likened polar regions mars experiments conducted examined identified inhabiting lake provided evidence virus horizontal gene transfer cold protective alterations identified connections multiple species ice water interface water column sediment established estimates life lake ice early spring growing season laser induced imaging techniques scientific divers team universe aquatic research solutions dove study unique communities
Lake Untersee