Saturday, September 09, 2023

 

Alaska scientists heading to Greenland for glacier research, museum project



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UNIVERSITY OF ALASKA FAIRBANKS




University of Alaska Fairbanks scientists will make several trips to Greenland over two years to study how meltwater and the ocean affect glacial ice loss. 

The four-year research project, funded by a $565,000 National Science Foundation grant, will create a traveling museum exhibit about the drivers of Arctic climate change. The exhibit will appear first at the University of Alaska Museum of the North, likely in 2026.

Ice loss from the polar ice sheets is the largest anticipated contributor to global mean-sea-level rise in the coming century. Scientists need to better understand glacier behavior to improve predictions of sea-level rise.

At the study’s conclusion, the researchers will create software that others can use to analyze the effect of runoff and ocean interaction on any of Earth’s glaciers.

Glacier flow is dictated by three main conditions: geometry, ocean conditions and surface melt.

“We don't quite understand why some glaciers react to some things and other glaciers react to other things,” said physics professor Martin Truffer, who specializes in glacier dynamics at the UAF Geophysical Institute and is helping lead the research. 

Truffer, who has made several Greenland research trips, and Ph.D. student Amy Jenson, one of last year’s recipients of a Geophysical Institute Schaible Fellowship, will go to Greenland to study Jakobshavn Glacier. The glacier, whose Greenlandic name is Sermeq Kujalleq, is a well-studied ocean outlet glacier in west Greenland.

Also involved in the research is geophysics professor Jason Amundson of the University of Alaska Southeast. Amundson was Truffer’s first doctoral student and studied Jakobshavn Glacier for his Ph.D. The research project’s principal investigator is Lizz Ultee, assistant professor of Earth and climate science at Middlebury College in Vermont.

The team will investigate the short- and long-term effect of runoff on outlet glacier flow, how a glacier’s geometry affects its response to runoff, and how variations in runoff speed and speed of movement of the glacier’s terminal area influence each other.

“When water gets to the base of a glacier, at bedrock, it lubricates the base and the glacier moves faster,” Truffer said. “But you can actually have a situation where more water means slower flow. That’s because the glacier’s plumbing system actually adjusts if you keep putting in more water. Water melts the ice, widening the channels and making the glacier more efficient at draining the water — and that slows the glacier’s speed.”

“If you want to predict the future of a place like Greenland, then you have to know how fast the ice is moving, and that is why we need to know more about the effects of runoff and geometry on a glacier’s speed,” he said.

Jakobshavn Glacier, which is about 40 miles long and a mile thick, has lost more ice than any other part of Greenland’s ice sheet. It had been in general retreat for a number of decades but was relatively stable in the 1980s and 1990s. In the late 1990s it underwent a massive retreat accompanied by much faster flow of the ice into the ocean. 

The glacier’s advance slowed beginning in 2013. Although the glacier was still advancing, the European Space Agency reported in 2019 that the glacier’s drainage basin was still losing more ice to the ocean than it gains as snowfall, “therefore still contributing to global sea-level rise, albeit at a slower rate.”

As for the museum component, details have not yet been confirmed. Truffer will work with Roger Topp, director of exhibits, design and digital media at the UA Museum of the North.

The exhibit will be a partnership with Ilulissat Museum in Ilulissat, Greenland. The community sits at the entrance to Disko Bay, which Jakobshavn Glacier feeds into.

Topp said the exhibit will concentrate on Greenland, since that’s the focus of Truffer’s research, but that it will include some information about Alaska.

Topp, who has also been to Greenland, said the exhibit could include a three-dimensional model of a glacier to illustrate the loss of mass.

“What can make it a spatial experience, where people walking around an object matters to how they understand it?” Topp said. “Sometimes it’s a harpoon head, sometimes it’s a painting, sometimes it’s a model built for the express purpose of showing a theory or the result of research.”

Museums in recent decades have de-emphasized their role as a source of information from experts only, Topp said.

“Museums have come away from that and moved toward presenting stories about objects,” he said. “An object has stories, and the museum collects those stories from many perspectives.”

Truffer hopes the exhibit tells a story.

“What I would like people to realize from the exhibit is that landscapes are dynamic,” he said. “We tend to think of these landscapes as pretty fixed in time, but they’re changing all the time.’’

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