Severe cold to test global warming

How severe will global warming be?

Geology team use coring system

Members of Jason Briner’s geology team use a coring system to sample Arctic mud on Baffin Island in the Canadian Arctic in an effort to gauge global warming.

Jason P. Briner, assistant professor of geology, is looking for an answer buried deep in mud dozens of feet below the surface of lakes in the frigid Canadian Arctic. His group is gathering the first quantitative temperature data over the last millennium from areas in extreme northeastern sections of the Canadian Arctic, such as Baffin Island.

Each spring, Briner travels to the region to sample Arctic lake sediments and glaciers, and analyzes them to reconstruct past climates. “As paleoclimatologists, we want to study Earth under conditions similar to those we have today, what we call ‘climate analogues,’ which might tell us what to expect in the future,” he says.

The Arctic as a region is an excellent harbinger of future change, Briner explains, because the signals or clues that signify climate change are so much stronger in the Arctic than elsewhere on the planet.

“Yet, even when we take that phenomenon into account, the signals we’re finding on Baffin Island are huge,” he says. “The temperature records—that is, the ‘signal’ of warmth that we’re reconstructing for this part of the Canadian Arctic over the past 10,000 years—seem to be higher than the global average for that period and even higher than the Arctic average.” The rapidity of the change also is exceptional, he adds.

“If we look at the temperature graphs that we’ve generated for the past 1,000 years for this region, the temperatures wiggle back and forth, so there is a little variability in there. However, in the past 100 years, both the magnitude and the rate of temperature increase exceed all the variations of the past 1,000 years.”

Briner and members of his team presented some of their data at the 37th Annual International Arctic Workshop in May 2007 in Iceland.