CANADA: Scientists were baffled last year after meltwater lakes atop Greenland’s ice sheet suddenly drained out at rates rivaling Niagara Falls.
Now a team of U.S. researchers says it has figured out the bizarre phenomenon and that could help them forecast global sea-level rise.
Vertical shafts in the ice sheet, called moulins, can funnel melt water beneath parts of the glacier and lift them up.
This causes cracks beneath the so-called supragalcial lakes that can empty them in hours , according to scientists from the Massachusetts Institute of Technology-Woods Hole Oceanographic Institution (MIT/WHOI) Joint Program in Oceanography.
Draining lakes can accelerate sea-level rise by suddenly injecting large volumes of water into the ocean and lubricating the flow of ice offshore.
