Melting Alaskan Glacier The Size Of Switzerland Could Threaten US Shoreline

ALASKA – A detailed “body scan” of Malaspina Glacier- one of Alaska’s most iconic glaciers- revealed that its bulk lies below sea level and is undercut by channels, making it likely to retreat faster than previously thought, according to a new study published in JGR Earth Surface.

The findings underscore the fragility of an extensive glacial system that could cause the largest ice loss from an Alaskan glacier within this century. At that point, it would also contribute a measurable volume to global sea level rise.

Lead author Brandon Tober, a UArizona Department of Geosciences doctoral student, and colleagues used the Arizona Radio Echo Sounder, or ARES. Previously, this instrument was used for a NASA-funded mission that recorded annual variations in the thickness of glaciers, sea ice, and ice sheets in Greenland, Alaska, and Antarctica from between 2009 and 2021.

The plane’s ice-penetrating radar “X-rayed” the glacier as it traversed it from the air, creating a complete “3D body scan” of the glacier and underlying bedrock.

The data indicated that the Malaspina glacier is mostly below sea level and has multiple channels cutting through its bed that go at least 21 miles from where the glacier meets the shore up towards its source in the Saint Elias Mountains.

“We can speculate that the channels, the big troughs beneath the glacier, are routing meltwater that comes out at the coast,” Tober said in a press release.

And that’s not all. The Malaspina Glacier is situated in Wrangell Saint Elias National Park and Preserve- the largest national park in the U. S. At 13.2 million acres, it’s bigger than Yellowstone National Park, Yosemite National Park, and the entire country of Switzerland put together.

“The potential loss of Malaspina and opening of a new bay along Alaska’s coastline may be the largest landscape transformation within the U.S. that we could witness during this century,” Tober said, “and it may lead to the loss of up to 500 square miles of park land.”

The full study was published in JGR Earth Surface and can be found here.