A new model yields insights into glaciers' retreats and advances

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A University of Alaska Fairbanks study looking at the physics of tidewater glaciers has yielded new insights into what drives their retreat-and-advance cycles and the role that climate plays in these cycles.

A University of Alaska Fairbanks study looking at the physics of tidewater glaciers has yielded new insights into what drives their retreat-and-advance cycles and the role that climate plays in these cycles.

Lead author and UAF geophysics doctoral student Douglas Brinkerhoff said the study in Nature Communications reveals that shifting sediments drive the cycles among tidewater glaciers in temperate climates such as southern Alaska.

The study also reveals that these glaciers don’t need periods of warming within the temperate climates to trigger the glacier’s retreat, as previously thought.

“Tidewater glaciers can advance further into the ocean by riding on top of a pile of their own sediment, but this can get them into trouble,” said Brinkerhoff.  “Eventually the glacier snout slows down, but it continues to push that sediment pile further out to sea, essentially pulling the rug out from under itself.  When the glacier floats, there’s no resistance at its base holding it back and the whole floating part tends to disintegrate.”

Read more at University of Alaska Fairbanks

Image: Martin Truffer drills holes for explosives in the surface of Taku Glacier. The explosions produce seismic waves that bounce off the sediment below the glacier, providing information about its thickness and character. (Credit: Douglas Brinkerhoff)