A new University of Colorado Boulder study reveals a level of warming in the Eastern Canadian Arctic that likely hasn’t been seen since the end of the last interglacial period 120,000 years ago. Radioactive carbon dates from 145 dead moss clumps emerging from four different receding Baffin Island ice caps show the mosses had not been exposed to the elements in at least 44,000 years.




Image © vtluvbug79

“The key piece here is just how unprecedented the warming of Arctic Canada is,” said study leader CU-Boulder geological sciences Professor Gifford Miller. “This study really says the warming we are seeing is outside any kind of known natural variability, and it has to be due to increased greenhouse gases in the atmosphere.”

The study is the first to show that the average summer temperatures during the last 100 years in the Eastern Canadian Arctic are warmer than the Early Holocene geological epoch, when the energy from the sun reaching the Northern Hemisphere was nine percent greater than today. Holocene began 11,700 years ago and continues to the present.

Baffin Island is located east of Greenland and mostly above the Arctic Circle in the Canadian province of Nunavut. It is the largest island in Canada and the fifth largest in the world.

Miller said that while the Arctic has been warming for more than a hundred years, notable warming in the Baffin Island region started around 1970. “And it is really in the past 20 years that the warming signal from that region has been just stunning. All of Baffin Island is melting, and we expect all of the ice caps to eventually disappear, even if there is no additional warming.”

+ Geophysical Research Letters Paper

Via Phys.org

Lead image via Gifford Miller, University of Colorado Boulder