Portland State geology Professor Andrew Fountain and a student team found Adams' glaciers have lost 49 percent of their coverage area since 1904, the Yakima (Wash.) Herald-Republic reported.
Over the same time period, nearby Mount Hood glaciers declined by 32 percent and Mount Rainier glaciers lost 24 percent of coverage.
Fountain said he was unsure why Adams' glaciers are declining at a faster rate.
"My educated guess is Adams is just over the east side of the crest of the Cascades. It doesn't get quite as much moisture," Fountain said.
Air temperatures in the Cascades are warmer than in other, higher-elevation mountain ranges, making snow more susceptible to gradually warming temperatures.
"When temperatures are close to melting temperatures, a slight warming can shift from snow to rain. That is what has been happening. The precipitation hasn't changed much, but it is switching from snow to rain," Fountain said.
"The key issue is that [snowpack] provides the most water when the landscape needs it the most, in the late summer," Fountain said. "Much of the plant community is stressed except those near the glaciers. They are a nice natural reservoir of water that provides habitat for some of these high-alpine animals and plants."