Up Close with River Piracy

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When UW Tacoma geoscientist Dan Shugar and his research colleagues arrived in the Canadian Yukon, they had firsthand experience with river piracy.

Getting Warmer with Piracy

Perhaps because of the striking combination of piracy and climate change, Dan Shugar’s research is getting a lot of attention in national media outlets. Stories about the research have appeared in:
New York Times, Washington Post, Guardian, Seattle Times, Q13Fox, Popular Science, Climate Central, Science News, CBC, CBC Radio The CurrentGlobe and Mail, USA Today, BBC World Service, Mashable, Christian Science Monitor, Gizmodo, Atlas Obscura, CBS News, TIME, US News & World Report, Daily Kos
…and many other outlets worldwide.

(The Kaskawulsh River, above, seen near its headwaters, is running higher now thanks to the addition of water that used to flow into the Slims River. Credit: Jim Best/University of Illinois.)

UW Tacoma geoscientist Dan Shugar is in the news with the publication of research into river piracy in the Canadian Yukon.

In this instance, “river piracy” refers to what happened when the leading edge of a glacier, melting due to climate change, retreated so far up its valley that all the meltwater changed course, abandoning one river in favor of another. The glacier in question is the Kaskawulsh Glacier in northern Canada, formerly feeding the Slims River north to the Bering Sea, now emptying into the Kaskawulsh River south to the Gulf of Alaska.

The study was published April 17 in Nature Geoscience, and, according to a UW news release, is “the first known case of ‘river piracy’ in modern times.” One of Shugar’s co-authors, John Clague, from Simon Fraser University, said the piracy “highlights the huge changes that glaciers are undergoing around the world due to climate change.”

The researchers had originally planned field work in August 2016 on the Slims River, to study a significant drop in the river level that had been reported by local pilots and a scientist with the Yukon Geological Survey. When they got there, the river was not just lower, “there was barely any flow whatsoever," Shugar said. "It was essentially a long, skinny lake. The water was somewhat treacherous to approach, because you’re walking on these old river sediments that were really goopy and would suck you in. And day by day we could see the water level dropping.”

Exposed sediments and dust storms at the Yukon's Kluane Lake, with Dan Shugar in the foreground. Lake level fall, due to piracy of the Slims River, has left the delta top exposed and prone to wind storms. Image credit: Jim Best/University of Illinois

Shugar and his colleagues regrouped, and went on to carefully document the changes in the glacier and landscape that caused the river diversion. Shugar says, "Being a geoscientist interested in very rapid geomorphic processes means that I am often working in landscapes where dramatic things have happened, and sometimes instantaneously."

And, to hear him speak about it, he loves it. "I still get giddy when I go into the field." Shugar says that the Kluane National Park and Reserve in Yukon Territory is one of his favorite places in the world. Conveying to his students and others the beauty and the power of nature in environments like that is what motivates him as a teacher and a researcher.

"When I'm describing landslides, or tsunamis, or river flows in class, I draw on examples from my fieldwork, and I think students like seeing a personal slant on topics they're learning about," said Shugar. He teaches courses in physical geography, geology and geomorphology.

Shugar also manages the Water, Sediment, Hazards, and Earth-surface Dynamics Laboratory (aka the waterSHEDlab), which is where he connects his undergraduate students directly into his active field research projects. "I love working with undergrads in the lab. It's very gratifying to see them get as excited about the science as I was during my undergrad years. These students do real work with me on projects. Some travel to field locations, and some are co-authors with my on published papers."

Dan Shugar in his office preparing for an interview with Discovery Channel.

Shugar's field work has taken him far afield, but some of his projects are closer to home. He is affiliated with the UW Freshwater Initiative, which brings together dozens of scientists from UW's campuses in Seattle and Tacoma who are engaged in research on freshwater resources. The Mountain to Sea Initiative, one of the major projects of the freshwater group, uses the Pacific Northwest as a "living lab" to study water sustainability, with the goal of translating and scaling findings to a national and global scale. One local setting that has piqued Shugar's interest is Alder Lake, a freshwater reservoir formed from the construction of Alder Dam on the Nisqually River. Shugar says the delta of deposited sediment that has naturally formed where the Nisqually enters the reservoir has changed dramatically recently, seemingly due to several years of low water levels in the reservoir. This summer, Shugar may take his remotely-operated research vessel to examine the changed delta. 

Besides Shugar, other co-authors on the river piracy study are John Clague at Simon Fraser University, James Best at the University of Illinois, Christian Schoof at the University of British Columbia, Michael Willis at the University of Colorado, Luke Copland at the University of Ottawa and Gerard Roe at the University of Washington. The study was funded by the University of Washington Royalty Research Fund, Parks Canada, Yukon Geological Survey, the Natural Sciences and Engineering Research Council of Canada, the University of Ottawa and the University of Illinois.

Written by: 
John Burkhardt / April 17, 2017
Media contact: 

John Burkhardt, UW Tacoma Communications, 253-692-4536 or johnbjr@uw.edu