A University of Colorado at Boulder study indicates meltwater periodically overwhelms the interior drainpipes of Alaska's Kennicott Glacier and causes it to lurch forward, similar to processes that may help explain the acceleration of glaciers observed recently on the Greenland ice sheet that are contributing to global sea rise.

"There are a number of catastrophic draining events of slush ponds on the Greenland ice sheet that may well promote increased sliding of the ice sheet as this water is jammed into a sub-glacial pipe system that is ill-prepared for such inputs," Robert Anderson said. "This phenomenon is also relevant to small glaciers around the world, because it may help to explain their nonsteady rates of sliding.