28 September 2018
By Joe Paxton
Researchers discovered the retreat of an ancient ice sheet from the western coast of Canada occurred earlier than previously thought.
Christopher Darvill from The University of Manchester’s Department of Geography is the lead author on a new paper published in Geophysical Research Letters, a journal of the American Geophysical Union.
Darvill and his co-authors studied the Cordilleran Ice Sheet in North America – which once covered an area the size of the Greenland Ice Sheet – to improve our understanding of past climate and ancient human migration.
The retreat of the ice sheet controlled when routes were opened that allowed ancient people to migrate south into the Americas. Which route was used – and when – remains a highly contentious topic among archaeologists and geologists.
Darvill and colleagues from universities in Canada and the U.S. used a helicopter to reach remote island locations along the Canadian coast. The team chipped rock samples from the tops of boulders and bedrock, before taking them back to a lab to investigate further.
The findings should help archaeologists target investigations tracing the migration pathways of early people into the Americas.
“Our work changes the model of when this ice sheet retreated in the past, improving our understanding of past climate change over western North America,” said Darvill. “The new findings add an exciting piece to the puzzle surrounding the colonization of the continent.”
–Joe Paxton is a news and media relations officer in the University of Manchester’s Division of Communications and Marketing. This post originally appeared as a news article on the University of Manchester’s website.