Melting glaciers reveal landscapes not seen in 40,000 years
Glaciers in the Canadian Arctic have melted enough to reveal land that was hidden for the last 40,000 years or more, researchers say.
And one big takeaway is this: The Arctic might be having its warmest century in at least 115,000 years, according to a study published this month in the journal Nature Communications.
“It’s not just a fluke,” University of Colorado Boulder doctoral researcher Simon Pendleton, lead author of the study, told CNN. “These ancient landscapes are being revealed over a broad geographic region on Baffin Island.”
For this study, scientists plucked 48 mosses and lichens — still rooted in the spots where they were killed by expanding ice millennia ago — from the edges of 30 retreating ice caps on Canada’s Baffin Island during summers from 2010 to 2015.
Using radiocarbon dating, the researchers found that most of the plants had been under the ice for at least 40,000 years, Pendleton said.
The plants were found in and around the island’s Penny Ice Cap region, in elevations ranging from several hundred meters to a mile above sea level. The recently exposed landscape, largely on plateaus between fjords, is dominated by boulders, bedrock and tundra vegetation.
“You’d normally expect to see different plant ages in different topographical conditions. A high elevation location might hold onto its ice longer, for example,” Pendleton said in a statement from the university. “But the magnitude of warming is so high that everything is melting everywhere now.”
Though they’re ancient, the collected plants are the same species as those that are alive and growing on the island today — not unusual, given that we’re looking at a span of tens of thousands of years as opposed to millions, Pendleton said.
The findings about the plants’ ages, combined with temperature data reconstructed from Greenland ice cores, suggest that this is the region’s warmest century in about 115,000 years, the study says.
“These trends are likely to continue and remove all ice from Baffin Island within the next few centuries, even in the absence of additional summer warming,” the study says.