Oregon Cascades, Western states losing glaciers, new analysis finds
(Oregon Capital Chronicle) Glacial melt from climate change is no longer just a problem at the poles.
Across the contiguous Western U.S., glaciers are slowly disappearing, according to a new analysis by researchers at Portland State University and the U.S. Geological Survey. The study was published in the journal Earth System Science Data Sept. 15.
Without glaciers, people, plants and animals are more vulnerable to late summer drought. Glaciers play an important role in regulating waterways, acting as a frozen reservoir that provides cool water for streams in the driest, hottest parts of summer when seasonal snowpacks have already melted. They also indicate the health of snowpacks needed to supply municipal water systems.
“You have apple orchards and pear orchards that get their water from the Middle Fork of the Eliot River in the Hood River Basin, and that’s glacial, that’s like two-thirds glacial fed in late August and September,” said Andrew Fountain, a Portland State University geology professor who led the study.
“Now is that important to the orchards? Frankly, I don’t know. But that water is probably going to go away,” he added.
Scientists have long tracked glacial melt in the North and South poles but as the effects of climate change spread, they’re now watching that effect in the West.
Of the 612 federally listed glaciers in California, Colorado, Idaho, Montana, Oregon, Washington and Wyoming, 50 are no longer considered glaciers given their size and condition, researchers found. Geologists consider glaciers to cover at least 25 acres. They’re made up of ice, snow, rock, sediment and exist in areas where the average temperatures are close to freezing, winter precipitation produces significant accumulations of snow or warmer temperatures the rest of the year don’t melt the previous winter’s snowpack, according to the U.S. Geological Survey.
Two glaciers, in Washington and Wyoming, have disappeared entirely. In the Cascade Range, 25 glaciers have been lost, including seven in Oregon.
Fountain said it’s possible that glaciers in the Oregon stretch of the range and any peaks south of Mount Hood could begin disappearing altogether in about 50 years.
“What this means is that our gorgeous summertime views of the mountains are going to become more like California, where they’re just kind of barren peaks,” he said.
Fountain and his team outlined and identified glaciers using maps compiled by the U.S. Geological Survey over 40 years, from the 1940s to the 1980s. They overlaid satellite imagery of the same areas taken between 2013 and 2020, coming up with a comprehensive inventory of 1,331 glaciers in the seven Western states, including the 612 federally listed glaciers. Most of the West’s glaciers are in Washington state: The glacial cover on Mount Rainier alone is larger than that of all the other states combined.
Of the eight glaciers that have disappeared in Oregon, six are now considered perennial snowfields, no longer moving and growing like a glacier. And two have gotten so small – smaller than two football fields – that they can no longer be considered glaciers. Most are in the Three Sisters area, Fountain said. One, the Benson Glacier in the Wallowas, is considered a snowfield.
The only glacier in the West that appears to be growing is Crater Glacier on Mount St. Helens. It’s on the north-facing side of the crater left by the 1980 eruption of the volcano and rapidly accumulated snow, rocks and ice pack and is continuing to move downslope.
Fountain will soon release another study showing the volume and area changes of the federally listed glaciers during the last century. He and his team see themselves as the reporters of the high alpine.
“We’ll keep tracking the glaciers as they go along and just kind of see what happens in that sense,” Fountain said, adding that the only thing that will slow glacial loss would be slowing of emissions of greenhouse gases.
“Frankly, we’re all kind of on our own on this,” Fountain said. “There is no state agency that is particularly concerned with the glaciers. It kind of falls between geology and hydrology. You can’t manage glaciers per se. So in that way, the state doesn’t have any interest.”