The long-term stability of the massive ice sheets of Antarctica, which have the potential to raise sea levels by hundreds of metres, has been called into question with the discovery of fast-moving rivers of water sliding beneath their base.
Scientists analysing satellite data were astonished to discover the size of the vast lakes and river systems flowing beneath the Antarctic ice sheets, which may lubricate the movement of these glaciers as they flow into the surrounding sea.

The discovery raises fresh questions about the speed at which sea levels might rise in a warmer world due to the rate at which parts of the ice sheets slide from the land into the ocean, scientists said at the American Association for the Advancement of Science in San Francisco.

“We didn’t realise that the water under these ice streams was moving in such large quantities, and on such short time scales. We thought these changes took place over years and decades, but we are seeing large changes over months. The detected motions are astonishing in magnitude, dynamic nature and spatial extent,” Dr Fricker said.

Scientists sound alarm over melting Antarctic ice sheets - Independent Online Edition