Alaska Glaciers Shrinking Fast: Survey
Date: 11-Aug-09
Country: US
Author: Yereth Rosen
Alaska Glaciers Shrinking Fast: Survey Photo: Lucas Jackson
Hikers walk on the Matanuska Glacier near Palmer,
Alaska.
Photo: Lucas Jackson
ANCHORAGE, Alaska - Three major glaciers in Alaska and Washington state
have thinned and shrunk dramatically, clear signs of a warming climate,
according to a study released Thursday by the U.S. Geological Survey.
The three glaciers -- Gulkana and Wolverine in Alaska and South Cascade
in Washington -- are considered benchmarks for those in alpine and
maritime climates because they closely parallel other glaciers in their
regions. They have also been the subject of close scientific scrutiny
since 1957.
"These are the three glaciers in North America that have the longest
record of mass change," said Shad O'Neel, a United States Geological
Survey glaciologist in Anchorage who was one of the study authors.
"All three of them have a different climate from the other two, yet all
three are showing a similar pattern of behavior, and that behavior is
mass loss."
Scientists are keeping a close watch on melting glaciers, as a rise in
sea-levels would threaten coastal and low-lying areas around the world.
The latest study compares records of snow and ice thickness and
densities over the years, the factors used to calculate mass. The
glaciers have lost mass as melting outpaced new snow and ice
accumulation, and for all three, the losses were especially dramatic
over the past 15 years, according to the USGS study.
By themselves, the glaciers and their changes are not proof of global
warming, he said. But their behavior fits with a pattern of warmer
weather or drier weather or both.
"It certainly says that the place where these glaciers are, the climate
is not supportive of healthy glaciers anymore," he said.
Ed Josberger, the Tacoma, Washington-based USGS hydrologist who
coordinated the study, said the results from the Gulkana, Wolverine and
South Cascade glaciers mirror worldwide trends.
"There is no doubt that most mountain glaciers are shrinking worldwide
in response to a warming climate," Josberger said in a statement
released by the Department of Interior.
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