A "hotspot" is melting the base of the Antarctic Ice Sheet at the South Pole. The area affected is three times that of Greater London. Scientists suspect a combination of unusually radioactive rocks and geothermal springs may be responsible.
The warm bedrock is removing some 6mm a year from the underside of the 3km-thick ice sheet, producing a mass of meltwater that then flows away through sub-glacial rivers and lakes towards the continent's coastline. The roughly 100km-by-50km hotspot came to light when researchers examined radar images of the ice sheet at 88 degrees South. This revealed a startling sagging in the ice layers directly above the hotspot.
Antarctica is in no danger of melting away as a result of this hotspot. In the grand scheme of things, the area affected and the amount of melting is simply too small to have a significant impact. But the knowledge adds to our understanding of the under-ice hydrology of the continent. There is vast network of sub-glacial rivers and lakes in Antarctica and they influence the way the ice sheet moves above them.
https://www.bbc.com/news/science-environment-46202255
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