Alaska's Glaciers Melting Faster Than Previously Thought - Star Tribune

[hatrack]

EDIT

Most of the glaciers stretching from Yakutat Bay to the Stikine Icefield, which goes into northwestern British Columbia, are thinning at twice the rate that was previously estimated, according to a new study co-authored by Hood's mentor, glaciologist Roman Motyka of the University of Alaska Fairbanks' Geophysical Institute.

Comparing radar mapping data from a space shuttle mission six years ago with air photos taken between 1948 and 1979, Motyka, UAF colleague Chris Larsen and three other scientists pinpointed the extent of the glaciers' volume change. They found that 95 percent of Southeast Alaska's glaciers are thinning. Some glacier surface elevations had dropped as much as 2,100 feet since 1948, such as the Muir Glacier in the popular Glacier Bay National Park and Preserve.

With the more precise data, they figured the rate of thinning was greatly underestimated from the last study done in 2002. The scientists calculated that an average of 3.5 cubic miles of glacier ice melts each year in the region due to a combination of climate change and glacier dynamics. They say even that may be an understatement of the actual rate of melting.

Mendenhall Glacier is a relatively small river of ice compared to the rest of Southeast Alaska's extensive network, but it stands out. It is Alaska's most visited glacier, drawing 367,000 people to the U.S. Forest Service's visitor center last year. The glacier is rapidly shrinking up the mountainside -- as rapidly as glaciers can, anyway. Visitors who have observed the glacier see the change themselves. Motyka estimated that the glacier's terminus will pull out of Mendenhall Lake entirely within 10 years. Hikers can trek up the side of the glacier along craggy rock that was under a deep layer of ice just two years ago. They can poke around in ice caves that weren't there at the beginning of the summer -- and which will be gone by the season's end.

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http://www.casperstartribune.net/articles/2006/09/24/news/regional/6ba48dcbf45548b4872571f20021036f.txt

[nam78_two]

1. k&r/nt

[BlueEyedSon]

2. Im cancelling my hike to Asia.

[Boomer]

3. An all too familiar refrain

>> Most of the glaciers ... are thinning at twice the rate that was previously estimated...

Which means we're screwed in half the time previously estimated.

[mom cat]

4. Or even less time if the change is exponential!

[Nihil]

5. It's certainly not going to be linear

I've never yet seen a natural valley (as opposed to a canal) that
has parallel sides and a flat bottom. This means that there is
significantly less volume in the bottom half of the glacier than
in the top half. Added to that is the fact that there are already
meltwater channels in the glacier, getting bigger every day, so
the last period of melting will be very rapid indeed.

Oops.