New research finds shrinking number of glaciers across the West  

When the pandemic hit, Andrew Fountain began looking for a project he could do from home. Uninterested in getting a sourdough starter or taking up woodwork, Fountain began counting glaciers.

More than three years later, Fountain, a geology professor emeritus at Portland State University, and research assistant Bryce Glenn have released a revised inventory of glaciers in the American West that will soon be added to the U.S. Geological Survey’s national map. The new inventory by Fountain and Glenn shows that 52 of the 612 officially named glaciers are no longer glaciers because they are either too small, no longer moving or have disappeared altogether. In Montana, six named glaciers have been added to the “missing” list. 

Fountain said their effort focused on the named glaciers across the western half of the continental United States because those were the most culturally significant. However, their inventory found that since the mid-20th century — about the time the USGS first started mapping the entire country — about 360 glaciers have either disappeared or become permanent snowfields. Fountain said the disappearance of glaciers shows just how much climate change is impacting the landscape across the American West. 

For a glacier to be a glacier, it must be at least 0.01 square kilometers (roughly the size of two side-by-side football fields) and it must be moving. Fountain said you can tell if a glacier is moving if it still has crevasses. 

In Montana, Fountain found six named glaciers that no longer qualify as a glacier, including ones in Mission-Swan Range, the Crazy Mountains, the Cabinet Mountains and the Lewis Range in Glacier National Park. Fountain said Montana has lost 76 glaciers since the mid-20th century. 

The USGS’ 7.5-minute maps — often printed on large pieces of paper that at one time, before the popularity of GPS maps, you could buy at the local outfitter — were first produced in the mid-20th century. All of the maps have been updated at least once, with others being updated more than once. But all of those updates missed one important detail, Fountain said. 

“For whatever reason, whenever they updated the maps, they always updated the infrastructure — roads, buildings and those types of things — but they never updated the glaciers,” he said. 

Using the USGS maps as a base, Fountain was able to use aerial images from the U.S. Department of Agriculture (which are taken every few years) to see just how much various glaciers across the West have shrunk. 

“It was a great COVID project because we were all stuck at home so it was kind of nice to sit at a computer and just look a beautiful landscapes all day,” he said. 

While it would be possible to conduct the research in the field, Fountain said, traveling to every glacier and taking measurements, trying to determine if it was still active, would have been overly time-consuming. 

Some glaciers have become perennial snowfields whereas others are rock glaciers, more rock than ice. 

“It was always a relief to find that a glacier was still a glacier,” Fountain said. “We were always cheering for them.” 

With the initial report out, Fountain and his team are now digging further into the data to see why some glaciers have shrunk faster than others and to put a number of just how much glacier ice has disappeared in recent decades. Fountain said the work his team is doing is beneficial to show just how much climate change is altering the landscape. 

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