 By PETER HALEY Tacoma News Tribune June 08, 2005
Yet the glaciers coating the mountain share troubling symptoms with the dwindling Gurshen glacier of Andermatt, Switzerland. The glistening masses of ice and snow that make 14,411-foot Mount Rainier shine aren't as impressive as they once were. The mountain shoulders 34 square miles of year-round ice, but at least five of its largest glaciers - Nisqually, Winthrop, Tahoma, South Tahoma and Carbon - are smaller than ever. When Swiss workers installed an $83 million blanket to stop Gurshen from wasting away this summer, scientists pointed to global warming as the reason. And while access to ski resorts isn't an issue on Mount Rainier, its glaciers and hundreds of others in Washington's Cascade Mountains are as vulnerable as those in the Alps. "Glaciers are really excellent indicators of climate change," said Jon Riedel, a North Cascades National Park geologist who tracks the health of six glaciers at North Cascades and Mount Rainier national parks. "The issue isn't whether it's getting warmer. Of course, it is. "The question is how fast and what are the consequences." People value glaciers not only for their beauty and as a lure to mountaineers, but also because glaciers are reservoirs. Glaciers hold water that eventually melts into streams, helps drive hydroelectric systems and sustains fish. Since the 1970s, virtually all of the glaciers outside the world's polar regions have shrunk, said Andrew Fountain, a Portland State University glaciologist who has studied glaciers throughout the western United States. Seventy-one percent of the West's glaciated areas are in Washington. "You don't find an advancing glacier anymore," Fountain said. Scientists describe growing glaciers as advancing. Retreat, in contrast, illustrates what happens when glaciers shrink. "Mount Rainier's glaciers aren't going away any time soon, but they're going to get a lot smaller," said Fountain. Most people notice the change at the glacier's terminus, also called the toe or snout, where the thaw is most obvious. "It's the graveyard for glacial ice," said Bill Bidlake, a U.S. Geological Survey hydrologist based in Tacoma. 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. "There's definitely a link between the climate and the change in the glaciers," Nylen said. After 1977, the shift became pronounced, and the rate of retreat among Mount Rainier's glaciers accelerated, he said. The same pattern of rapid retreat also is evident in the North Cascades, said Fountain. Publish A Letter on SitNews Read Letters/Opinions Submit A Letter to the Editor
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