Lubricating lakes

摘要

More than 150 subglacial lakes have been discovered beneath the Antarctic ice sheet. The four most recent additions, found right at the start of fast flow in a large ice stream, suggest that the lakes influence ice dynamics. Antarctica is well known as the coldest place on Earth, but it is also surprisingly wet. Whereas the upper part of the ice is cold, geothermal heat and the insulating effect of the overlying ice combine towards its base to bring extensive areas of ice at the bed to its melting point. In the most extreme cases, lakes form beneath the ice sheet.