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Ice bound
Neal Iverson has a unique opportunity to study glaciers, but look
what he has to go through.
Imagine for a moment that you are living beneath an icepack 700 feet
thick. The temperature is a constant 35 degrees Fahrenheit. Humidity stays
at 100 percent, 24 hours a day.
Your only opportunity to see the sun is a 30-minute walk down a tunnel,
once a day.
Doesn't sound very appealing does it?
Neal Iverson doesn't care. The assistant professor of geology will spend
three months this spring in exactly that environment, and he couldn't
imagine a better place to be. After all, it's all in the name of science.
Iverson will spend March 10 through April 2 in Norway's Svartisen Glaciological
Observatory, a tunnel cut underneath the Svartisen Ice Cap. The tunnel
was constructed in 1993 by a Norwegian utility company, which uses the
water from the glacier for hydropower.
"There is dripping water all over the tunnel," Iverson said.
"It's not a pleasant place for a work environment.
"But it's a great natural lab to study glaciers and glacier motion."
Iverson's research, which is funded by the National Science Foundation,
involves field and laboratory experiments aimed at better understanding
surficial processes, particularly those in glacial environments. His work
with the Svartisen Ice Cap focuses on glacier flow, erosion and sedimentation.
Iverson has worked at the Svartisen Ice Cap on two different occasions,
once in 1993 and then again during the 1996-97 academic year. When he
returns this spring he will be accompanied by a former student, Tom Hooyer
of the Wisconsin Geological Society, and the co-PI on the project, Denis
Cohen, a former advisee of Iverson's and a research associate at Yale
University. Two of Iverson's current graduate students will also accompany
the group.
While the working environment where Iverson will spend three weeks isn't
ideal, what the glacier and subglacial laboratory provide is.
"This glacier rests directly on rock," he said. "The experiments
we're going to do will allow us to study how ice moves over the rock bed.
If we understand how glaciers move, then we can better understand their
effect on the overall climate system."
Typically geologists are forced to bore holes into glaciers to get readings
on how a glacier moves over a rock bed. Or experiments are conducted in
labs that stimulate the movement of ice on sediment and rock.
At the Norway glacier, Iverson and his colleagues can actually get between
the ice and rock in that less than ideal work environment.
"We can actually get under the ice," he said. "When we
have to bore holes into the glacier, we can't really see what is going
on."
In his previous studies, Iverson's research indicated that ice at the
bottom of glaciers is softer and flows easier than ice higher in glaciers.
This time he will conduct experiments to help determine:
* What controls friction between the bottom of the glacier and the rock
underneath it, and
* How ice moves at the bottom of the glacier if there is a layer of wet
sediment between the ice and rock.
"The results from these experiments will help us build mathematical
models for predicting how fast glaciers move," Iverson said.
"We can study some of these processes with laboratory experiments,
but you have to attack these problems in as many ways as possible,"
he continued.
Around LAS
April 9-15, 2001
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