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Red River Valley

Summertime meltwater forms lakes on Greenland’s ice sheet that suddenly disappear. WHOI glaciologist Sarah Das showed why—the water’s weight cracks the ice, draining to bedrock and lubricating the ice’s seaward flow. In 2008 Das and colleagues investigated this unseen plumbing, pouring harmless dye into inland draining meltwater while grad student Maya Bhatia tested for dye in coastal seawater. “Knowing the speed of water flow under the ice would help us determine what sort of water system exists there,” Das said. “A warming climate may cause more meltwater lakes and cracks to form, which could speed ice flow, leading to increased rates of sea level rise.”

(Photo by Chris Linder, Woods Hole Oceanographic Institution)