High school students map glacier with GPS, sonar technology

For the first time since the pandemic, Wrangell High School students traveled to Shakes Glacier to survey the area and measure the rate that the glacier is receding. Students have been recording the glacier's movements since 2011.

This year's cohort included freshman Andrei Bardin-Siekawitch, junior Aubrey Wynne and junior Della Churchill. The trio submitted applications to join the Sept. 7 trip, where they learned about surveying technology, data collection and environmental changes. They also attended a week of lunch meetings in early September to learn about the surveying process and its history.

For Wynne, the project presented an opportunity to get more involved in her community. For Bardin-Siekawitch, it was a way to learn more about technology and geophysics, which he has been interested in since participating in an Upward Bound summer program.

"I thought it would be a good experience just to learn a little bit more about what they do with these types of projects," Churchill added.

The students set up the surveying equipment and used GPS technology to compare the glacier's current location to previous years. They also collected water samples at various depths to test the distribution of sediment in the lake.

From 1999 to 2011, the glacier retreated about 5,000 feet along the right side of the bedrock around Shakes Lake, facing the glacier, according to maps compiled by the team. Between 2011 and 2017, it retreated about 2,000 feet.

The glacier is about 20 air miles northeast of downtown Wrangell, halfway between the Stikine River mouth and the Canadian border.

The high school team hasn't yet analyzed the data from this year yet, but in the coming months it will graph the survey results and prepare a presentation.

The project is a collaboration between the school, Eric Yancey and Jenn Miller-Yancey of Breakaway Ferry and Freight, Mike Howell of R&M Engineering and the U.S. Forest Service. This year, University of Oregon oceanographer David Sutherland also joined the group, and plans to continue participating in future surveys.

Sutherland's team has studied LeConte glacier since 2016 and has recently started a new project on lake-terminating glaciers. "In general, when people think of glaciers, you might think of mountain glaciers," or land-terminating glaciers, he said. Marine-terminating glaciers end in the oceans and lake-terminating glaciers end in freshwater.

"What people have found is that the retreat rates of land-terminating versus lake- or marine-terminating ... those different classes of glaciers are behaving differently," he said. "It's pretty obvious that if a glacier is terminating in the ocean, it might experience different environmental conditions."

He brought a sonar system along with him to provide a 3D underwater map of the ice's shape. "The underwater shape tells us something about how the lake affects the glacier," he said. "It's pretty neat."

He hopes to keep his collaboration with Wrangell High School going and is seeking permission to do drone mapping at the site in the future.

The findings from past years are available at whsshakesglaciersurveyteam.weebly.com.