Apr 17, 2017

River piracy and drainage basin reorganization led by climate-driven glacier retreat

Daniel H. Shugar, John J. Clague, James L. Best, Christian Schoof, Michael J. Willis, Luke Copland and Gerard H. Roe
Nature Geoscience
  • States that stream piracy has been investigated in glacial environments, but so far it has mainly been studied over Quaternary or longer timescales
  • Documents how retreat of Kaskawulsh Glacier—one of Canada’s largest glaciers—abruptly and radically altered the regional drainage pattern in spring 2016
  • Uses hydrological measurements and drone-generated digital elevation models to show that in late May 2016, meltwater from the glacier was re-routed from discharge in a northward direction into the Bering Sea, to southward into the Pacific Ocean
  • Concludes that this instance of river piracy was due to post-industrial climate change, based on satellite image analysis and a signal-to-noise ratio as a metric of glacier retreat
  • Emphasizes potential downstream impacts on ecosystems, sediment and carbon budgets, and communities that rely on a stable and sustained discharge