NSF PR 02-20 - March 25, 2002
Crossing Alaska By Snowmobile in Search of Climate-Change
Clues
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To follow the progress of the science
party in their own words and pictures,
see the following list
of dispatches. |
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A group of scientists left Nome, Alaska late last week
on a 35-day snowmobile traverse to scour the Alaskan
tundra for clues to the role snow cover plays in climate
change. The team also will analyze the chemistry
and composition of snow along the route to determine
the source of the snow, and how much it has been affected
by arctic haze.
Supported by the National Science Foundation (NSF),
the six- member Snow Science Traverse – Alaska Region
(SnowSTAR 2002) expedition plans to cover 1,100 kilometers
(700 miles) -- from Nome, northeast through the Brooks
mountain range to Barrow. The team plans to sample
snow at more than 75 locations.
The traverse is part of an ongoing larger project to
understand climate change in the arctic, titled ATLAS
(Arctic Transitions in Land Atmosphere System) and
sponsored by the Arctic System Science program within
NSF's Office of Polar Programs. Matthew Sturm, of
the Army's Cold Regions Research and Engineering Laboratory
at Fort Wainwright, Alaska will lead the team.
The team will measure snow depth, density and layering
during the traverse, and will make detailed measurements
of snow layering or stratigrapy. These measurements
will be used to determine regional trends in the snow
properties.
Several lines of evidence indicate that climate change
is likely to be amplified in the arctic and therefore
easier to detect there than at lower latitudes. Air
temperatures in the Alaskan arctic have increased
two to four degrees Celsius in the past 30 years,
and evidence suggests changes are already occurring
in terrestrial ecosystems. Snow covers the arctic
for seven to 10 months of the year and is thought
to play a key role in this process of change.
The researchers will be looking at two processes:
the role of key weather events in the development
of the snow pack, and the interaction of the snow
and vegetation. Previous studies have shown that
arctic snow pack consists of between five and eight
layers of snow deposited by a like number of storms.
Chemical sampling of the snow will help determine if
there is a difference between the winter precipitation
source for the arctic slope versus south of the Brooks
Range and if the precipitation source changes through
the winter as the Chukchi, Beaufort, and Bering Seas
freeze. By tracing the snow’s chemicals, such as
calcium, magnesium, and various isotopes such as Boron
and Deuterium, the team hopes to pinpoint where the
snow originated and its atmospheric history. The
data gathered during the traverse will help show how
key meteorological events determine the characteristics
of the snow.
The studies related to snow and vegetation are motivated
by previous findings that the presence of shrubs may
promote further shrub growth by increasing the amount
of snow on the ground. Climate warming also promotes
increased plant production, so the two processes may
feed back in complex ways.
Snow measurements will be taken along the tundra-forest
boundary between Council and Ambler, a small village
on the Kobuk River. North of the Brooks Range, measurements
will be taken on the tundra. The tundra north of
the Brooks Range is much less shrubby than the tundra
of the south range.
April Cheuvrant, a teacher at Table Rock Middle School
in Morganton, N.C., will accompany the traverse as
part of NSF's Teachers Experiencing the Arctic and
Antarctic (TEA) Program. She will assist in conducting
sampling and interacting with Native Alaskans in villages
along the traverse route.
To follow the progress of April Cheuvrant's trip, see
her journal on the TEA Web site: http://tea.rice.edu/tea_cheuvrontfrontpage.html
For more information about the TEA program, see: http://www.nsf.gov/od/lpa/news/media/01/fstea.htm
For more information about NSF's arctic sciences section,
see: http://www.nsf.gov/od/lpa/news/media/01/fsarctic.htm
For more information about how NSF meets the challenges
of conducting science in the polar regions, see: http://www.nsf.gov/od/lpa/news/media/01/fslogistics.htm
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