The Next Generation of Explorers
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In the University of Maine Climate Change
Institute, more than 50 faculty members and research staff in
disciplines from anthropology, glaciology and paleoecology to
geoarchaeology and numerical modeling collaborate to gain perspective on
the past in order to make better predictions for the future. Conducting
research throughout the world in conjunction with those faculty are more
than 25 graduate students and postdoctoral fellows, as well as a handful
of undergraduates — the next generation of explorers.
UMaine Today magazine asked four of the young explorers from Maine —
Alice Doughty, Aaron Putnam, Sean Birkel and Sam Kelley — what attracted
them to research in such remote locations as New Zealand, Antarctica,
Patagonia and Iceland. They describe the challenge and the questions yet
to be answered.
Sean Birkel of Bangor is a third-year Ph.D. student in Quaternary
geology and glaciology whose fieldwork has taken him to Antarctica, New
Zealand, Iceland and the Western United States
Birkel studies ice sheets and how they interact with the global climate
system. His dissertation examines the formation and evolution of the
Laurentide Ice Sheet over North America, and the mechanisms by which
that ice sheet disappeared.
"The most exciting thing to me is visiting pristine landscapes not yet
spoiled by us humans," says Birkel, talking about what excites him about
his area of research. "As a science educator, I hope to impress upon
students that we belong to the Earth more so than the Earth belongs to
us. The survival of our civilization is dependent upon this basic
understanding."
Aaron Putnam is a second-year Ph.D. student from Chapman who is using
glacial geology and a geochemical technique called beryllium-10
surface-exposure dating to reconstruct the history of ice ages and
abrupt climate changes on a near-global scale.
"One of the fundamental questions in Earth sciences is: What causes ice
ages?" says Putnam, who conducts fieldwork in the New Zealand Southern
Alps, the Patagonian Andes in southern Argentina and the Rocky Mountains
in Wyoming. "The ice ages are the most distinct climate oscillations to
affect the globe over the last 2,500,000 years, yet scientists still do
not understand why they occur. Perhaps even more important, we cannot
explain why the great ice ages ended so abruptly."
Through his research, Putnam hopes to shed light on what causes and ends
glacial cycles, which is fundamental to our understanding of climate
dynamics, and is important for improving models used to predict future
climate behavior in response to anthropogenic greenhouse gas emissions.
He is working with others at UMaine and the Lamont-Doherty Earth
Observatory of Columbia University to develop a global stratigraphic
model of climate by reconstructing the history of the great ice age
glaciers from the geological features they left behind.
Alice Doughty of Sebago is a second-year master’s student in glacial
geology who also has done field work in Wyoming, as well as Antarctica
and New Zealand. Her research investigates a period about 20,000 years
ago when temperatures were colder and large ice sheets occurred. The
questions to be answered: What caused the cooling and was it a global
event?
One of the leading theories of glacial cycles suggests that the ice ages
were out of sync between the two polar hemispheres, but field results do
not support this, says Doughty. She has found that the timing of the ice
advance in the Northern and Southern Hemispheres was relatively
concurrent, which means the glaciers likely responded to a global
signal.
"It is exciting to work with the leaders of the climate change field,
and to contribute to the scientific community," Doughty says. "I hope to
continue working on these types of problems and perhaps make some
significant advances in the field."
Sam Kelley of Orono is in the first year of his master’s work in
Quaternary geology and geomorphology. In his research area on the
eastern shore of Lake Pukaki on the South Island of New Zealand, Kelley
is using a technique called terrestrial cosmogenic nuclide exposure
dating to determine when glaciers deposited boulders on the moraines.
Because glaciers are very sensitive to even the smallest climatic
changes, maps of past glacier positions can be used to better understand
what the past climate was like.
Data from New Zealand can be compared to various other climate data
worldwide in an effort to understand which mechanisms affect the Earth's
climate, and on what timescales they can act.
"I really enjoy seeing the parts of the puzzle coming together," Kelley
says. "For instance, one set of moraines in my field area appears to
correlate well with glaciers in North America and Europe.
"In science, my work forms a part of a larger project, which is working
to find the cause of the end of the most recent major glaciation on
Earth," he says. "This question is probably one of the most important to
climate scientists today, as understanding why ice ages end will go a
long way in understanding what mechanisms cause ice ages and allow them
to persist."
by Margaret Nagle
September-October, 2008
