Antarctica's Hidden Lake: How Lake Vostok Stays Liquid Beneath Four Kilometers of Ice
Beneath roughly four kilometres of Antarctic ice at Vostok Station, Lake Vostok—about the size of Lake Ontario—remains liquid thanks to insulation by the ice, a pressure-lowered melting point, and a steady geothermal heat flux that keeps the basal boundary near the melting point. The ice’s slope creates zones of melting and freezing, driving circulation and a slow exchange with accretion ice at the bottom. The lake has likely stayed isolated for about 15 million years from sunlight and direct atmosphere, though the water itself is mobile and the exact ages of water or material differ; while microbes have been detected in accretion ice, clean evidence from the main water column is hampered by drilling contamination, so a robust biological census remains elusive.
