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"Glaciers need new snow to survive. The decline of Washington’s glaciers parallels a record of dwindling mountain snowpack measured between 1950 and 2000, scientists said. Warmer winter temperatures mean more rain instead of snow. As the snow level rises, glaciers typically retreat to higher altitudes. “Glaciers amplify what’s happening,” Riedel said. “Not just year to year, but over five, 10 or 50 years.”
The most up-to-date analysis of what has happened at Mount Rainier, home to the largest glaciers in the contiguous United States, was done by Thomas Nylen, a Portland State University glaciologist. He used aerial photographs to calculate the difference in glacier volume and area between 1913 and 1994. During that time, the mountain’s glaciated area declined by one-fifth. The combined volume of the glaciers dropped by one-quarter. Retreat is more pronounced on the south side of the mountain, where glaciers are smaller and might accumulate less snow, he said.
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In North Cascades National Park, located in the most heavily glaciated area in the lower 48, some small glaciers have already disappeared. Over the past 150 years, 40 percent of the glacial ice and snow within the park has vanished, Riedel said. Thirteen percent of the loss has occurred over the last 40 years."
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http://www.thenewstribune.com/news/local/story/4912595p-4501265c.html