The state of Alaska
has the dubious distinction of leading the lower 48 in the effects of a warming
climate. Small villages are slipping into the sea due to coastal erosion; soggy
permafrost is cracking buildings and trapping trucks.
In an effort to better understand how the Pacific
Northwest fits into the larger climate-change picture, scientists
from the University of New Hampshire (UNH) and University
of Maine are heading to Denali
National Park on the second leg of
a multi-year mission to recover ice cores from glaciers in the Alaska
wilderness.
Cameron Wake of the UNH Institute for the Study of Earth,
Oceans, and Space (EOS) and Karl Kreutz of the University
of Maine Climate Change Institute
are leading the expedition, which is funded by the National Science Foundation.
This year’s month-long reconnaissance mission will identify
specific drill sites for surface-to-bedrock ice cores that will provide
researchers with the best climate records going back some 2,000 years. The
fieldwork is part of a decade-long goal to gather climate records from ice
cores from around the entire Arctic region.
“Just as any one meteorological station can’t tell you about
regional or hemispheric climate change, a series of ice cores is needed to
understand the regional climate variability in the Arctic,”
says Wake, research associate professor at UNH. “This effort is part of a
broader strategy that will give us a fuller picture.”
Kreutz says the 2,000-year ice core record will provide a
good window for determining how the climate system has been affected by
volcanic activity, the variability of solar energy, changes in greenhouse gas
concentrations and the dust and aerosols in the atmosphere that affect how much
sunlight reaches the Earth.
“This is a joint effort in the truest sense,” says Kreutz,
who has collaborated with Wake in both Arctic and Asian
research for the better part of a decade.
Wake conducted an initial aerial survey of the Denali
terrain two years ago but notes there have been “no boots on the ground.”
Through May, Wake, his Ph.D. student, Kreutz’ UMaine research team, and
Canadian ice-core driller Mike Waszkiewicz will visit potential deep drilling
sites and use a portable, ground-penetrating radar to determine the ice
thickness and internal structure on specific glaciers. They will be looking for
“layer-cake” ice with clear, well-defined annual stratigraphy.
At the potential drill
sites, the scientists will also collect samples for chemical analysis from
20-foot-deep snowpits and shallow ice cores, and install automatic weather
stations at 7,800 feet and 14,000 feet. The chemical analyses, which will be
carried out at both UNH and UMaine labs, are needed to decipher changes in
temperature, atmospheric circulation, and environmental change such as the
phenomenon known as “Arctic haze,” which, for decades, has brought heavily
polluted air masses to the region from North America, Europe and Asia.