For the First Time on Record, Climate Change Has Rerouted an Entire River
A stream flows through the toe of Kaskawulsh Glacier in the Yukon. In 2016, this channel allowed the glacier’s meltwater to drain in a different direction than normal, resulting in the Slims River water being rerouted to a different river system. (Dan Shugar)
Author: Chris Mooney, The Washington Post
A team of scientists Monday documented what they’re describing as the first case of large-scale river reorganization as a result of human-caused climate change.
They found that in mid-2016, the retreat of a very large glacier in Canada’s Yukon territory led to the rerouting of its vast stream of meltwater from one river system to another – cutting down flow to the Yukon’s largest lake, and channeling freshwater to the Pacific Ocean south of Alaska, rather than to the Bering Sea.
The researchers dubbed the reorganization an act of “rapid river piracy,” saying that such events had often occurred in the Earth’s geologic past, but never before, to their knowledge, as a sudden present-day event. They also called it “geologically instantaneous.”
“The river wasn’t what we had seen a few years ago. It was a faded version of its former self,” said lead study author Daniel Shugar of the University of Washington, Tacoma of the Slims River, which lost much of its flow due to the glacial change. “It was barely flowing at all. Literally, every day, we could see the water level dropping, we could see sandbars popping out in the river.”
The study was published in Nature Geoscience. Shugar conducted the study with researchers from six different Canadian and U.S. universities.