With the winter snow arriving in late October, the 2021-2022 water year for the Central Cascades came to an end and it was a bad year. Almost all glaciers in the 3 Sisters-Broken Top region had no snow remaining on them at the end of the summer. They had no additions of mass, only mass loss at all elevation. This is very very bad. The exceptions are Hayden and Diller Glaciers on Middle Sister and Lewis Glacier on South Sister, which had some snow in late October remaining (Collier had a minute amount, discussed below). Nevertheless, these glaciers also had net mass losses as their snow gains did not outweigh the summer melt. Notably, this makes multiple no-snow years for Prouty, Bend, and Crook Glaciers.
Collier Glacier, where we have direct measurements of how much snow coverage is needed to have the glacier be in equilibrium (melt=snow), had only 4% snow coverage on October 21; it needs 70% coverage to be in equilibrium!
This makes the third year in a row where Collier had no snow, or essentially no snow, accumulation. Another such year was 2018. Thus, four out of the last six years have been too warm to sustain glaciers in the 3 Sisters/Broke Top region. In short, human greenhouse gas levels are already too high for Central Oregon; continued greenhouse gas emissions will only hasten the transition of this region into an ice-free landscape.
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