NIU students become globetrotters on quest to understand global warming
Favorite entrée of ancient Peruvians holds climate clues September 29, 2008
by Tom Parisi
Research on global warming took two NIU students nearly to the ends of the earth this past summer, with one traveling to South America and the other to the Arctic Circle.
Both Jennifer Cumpston and Brittani Duhamel in the Department of Geology and Environmental Geosciences are working with Professor Paul Loubere to examine how forces in the equatorial Pacific Ocean drive climate change worldwide and how Polar Oceans connect to the Tropics.
The student researchers want to better understand the effects of the El Niño Southern Oscillation (ENSO), which influences climate patterns worldwide. ENSO is a mighty coalition of forces that sways across the equatorial Pacific and drives pools of warm surface water either to the west, causing La Nina ocean-atmospheric conditions, or to the east, resulting in El Niño conditions.
The 23-year-old Cumpston traveled with Loubere to Peru, where they met up with NIU Anthropology Professor Winifred Creamer. She and her husband, Jonathan Haas of the Field Museum in Chicago, are conducting a long-term project examining the emergence of complex societies on the north-central Peruvian coast.
Creamer and Haas have excavated 13 separate sites, uncovering ceremonial monuments and dwellings dating back to the 3rd millennium B.C. But Cumpston is most interested not in what the ancient coastal dwellers built but rather what they ate and threw away.
It turns out these ancient South Americans had diets rich in fish and shellfish, including a clam with the scientific name of Mesodesma donacium. When alive, the clams captured month by month the conditions of the ocean. Scientists can retrieve this information through oxygen isotope readings.
“They left us piles of clam shells in their trash heaps,” Loubere says. “What once was their food now is our window into their world.”
As part of her Ph.D. dissertation, Cumpston is unraveling the mystery of past climates and El Niño and La Niña conditions through careful measurements taken from the clams at key times in human pre-history.
“Dr. Loubere is teaching me how to do the oxygen isotope measurements and how to interpret and analyze what the results mean for ocean processes,” Cumpston says. “It’s all linked to climatology.”
Cumpston says this is the type of work she envisioned when she enrolled in NIU’s graduate program, but she never thought her research would include digging in the dirt.
“I got involved in the archaeology and dug a site myself,” Cumpston says. “I’ve had a lot of incredible opportunities, being able to work with experts in the field and from the Field Museum. I’m going to conferences this fall to present my work.”
Meanwhile, graduate student Brittani Duhamel headed in the opposite direction in order to conduct her research. She and Loubere spent a portion of August in Svalbard, a Norwegian island territory replete with glaciers and wildlife—including exotic birds, dolphins and Arctic ice seals.
Midway between Norway and the North Pole, Svalbard would seem a world away from coastal Peru, but the two regions hold something in common: both are deserts—one in dry heat, the other in silver cool light.
The Arctic is on the receiving end of Tropical heat. The Gulf Stream, with its roots in equatorial waters, eventually makes its way north to the Arctic. While the polar ice cap reflects solar energy, in effect rejecting the melting sunlight, its underside is being eaten away by the warm ocean waters.
The research and travel for both Cumpston and Duhamel was funded through a combination of grants from the National Science Foundation, the National Oceanic and Atmospheric Administration, the Norwegian Research Council and private sources.