SOURCE: Science News

DATE: October 26, 2017

SNIP: Some mosses in the eastern Canadian Arctic, long entombed in ice, are now emerging into the sunlight. And the radiocarbon ages of those plants suggest that summertime temperatures in the region are the warmest they’ve been in tens of thousands of years.

As the planet warms and the ice retreats on Canada’s Baffin Island, the change is revealing plants long buried beneath the ice. And in some locations, the emerging plants last saw the sun at least 45,000 years ago — and possibly as much as 115,000 years ago. Paleoclimatologist Gifford Miller of the University of Colorado Boulder reported the finding October 22 at the Geological Society of America’s annual meeting. “We were stunned,” Miller said.

Miller’s team has collected an impressive number of samples and their findings are very compelling, said geomorphologist Lee Corbett of the University of Vermont in Burlington, who was not involved in the study. “It truly is an indication that humans are pushing the climate into a new regime, one that modern, agriculture-based civilizations have never witnessed.”

Originally, the researchers expected to find plants dating to medieval times, which would have suggested that the region is the warmest it’s been since the Middle Ages. But finding 3,700-year-old plants was a surprise, Miller said. And “we never anticipated we’d find plants 40,000 years old,” he added. “It’s a bit spooky because it provides quantitative evidence that the magnitude of summer warmth is already sufficient to melt all ice in the eastern Canadian Arctic. It’s just a matter of time now.”