UMass Amherst geoscientists unravel Greenland’s climate history

Geoscience graduate students Greg DeWet and Daniel Miller assisted Raymond Bradley.
Geoscience graduate students Greg DeWet and Daniel Miller assisted Raymond Bradley. | File photo
To better understand Southern Greenland’s history, an earth sciences team from UMass Amherst recently traveled to the large, rugged island to obtain sediment samples and construct a theory for how climate changes have impacted settlement there.
 
“In general we know more about what has happened in the Arctic and up on the ice cap … but when you come down to the coast, there’s not very much known about this area,” said Raymond Bradley, Ph.D., director of the Climate System Research Center at the University of Massachusetts Amherst and study leader.
 
Geoscience graduate students Greg DeWet and Daniel Miller assisted Bradley. While stationed in Greenland, they dined on reindeer — and whale, which Miller termed “interesting” — and enjoyed the opportunity to interact with residents and learn their history. Vikings settled the land, with remains of Norse farms still in evidence today.
 
“They raised sheep and cattle from about 985 A.D. to the early 1400s,” said Bradley. “The question is: what was the climate like and did it change enough to cause the settlers to abandon the sheep farms?”
 
By pulling up sediment core samples lifted from the lakes of southern Greenland, the scientists can “look back in time.” Bradley said a 1.5-meter sediment sample should enable the team to create a profile of the past 3000 years, by looking for organic bio-markers produced by bacteria and algae that denote chemical composition changes in response to temperature.
 
The researchers expect to be able to reconstruct temperature change and hopefully what the climate was like during the Viking era, with plans to create a website devoted to North Atlantic climate change in the near future.