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Home / Science / Arctic glacial meltings have been revealing hidden land for more than 40,000 years

Arctic glacial meltings have been revealing hidden land for more than 40,000 years



Melting ice exposes hidden landscapes in the Canadian Arctic that have not been seen for more than 40,000 years, as new research published in Nature Communications shows.

Unsurprisingly, the study indicates that climate change is the driving force behind this record-breaking glacier retreat. As Arctic temperatures increase with increasing speed thanks to strong positive feedback loops in the polar regions, we can expect things to warm up even faster. The near future. According to researchers from the University of Colorado Boulder, the Canadian Arctic can see its warmest century in 115,000 years.

"The Arctic is currently warming two to three times faster than the rest of the world, so glaciers and ice caps will of course react faster," said Simon Pendleton, principal author and PhD student at the CU Boulder Institute of Arctic and Alpine Research (INSTAAR) said in a statement.

Pendleton and colleagues' research is based on plants collected on the edge of ice caps on Baffin Island, the fifth largest island in the world. The landscape is characterized by deeply cut fjords and high plateaus with low relief. The latter conserves lichen and moss in their original position in the ice for thousands of years ̵

1; a bit like a cryochamber.

Earlier observations indicate that the foliage is soon "removed" from the environment as soon as it loses its protective layer of ice, either through meltwater in summer or through the wind in winter. This allows scientists to reasonably assume that the vegetation collected today is vegetation that has been covered with ice since its initial growth phase. As such, it provides a decent barometer of how far and how fast glaciers are retreating.

Read more: Greenland is approaching the threshold of an irreversible melt, and the consequences for coastal cities could be bleak

Baffin Bay, Nunavut, Canada.
City Escapes Nature Photo / Shutterstock

"We travel to the retreating ice margins, sample newly exposed plants conserved on these ancient landscapes, and carbon date the plants to get a sense of when the ice has last passed through this place, "Pendleton explained.

"As dead plants are efficiently removed from the landscape, the root crop radocarbon age is the last time that the summers were on average as warm as in the previous century."

In total, the team collected 48 plant samples from 30 ice caps on Baffin Island and quartz samples used to confirm the age and ice history of the environment. Laboratory analyzes indicate that plants in all 30 ice caps were probably preserved on a constant ice surface over the past 40,000 years or more.

Meltwater flows through Baffin Island.
INSTAAR / Youtube

The results were then compared to the temperature data obtained from Grubland and Baffin Island ice cores. The last 100 years have been the warmest in 115,000 years of the region.

"Unlike biology, which has developed plans over the past three billion years to avoid the effects of climate change, glaciers have no survival strategy," said Gifford Miller, professor of Earth Sciences at CU Boulder.

Vegetation found under the molten ice.
INSTAAR / Youtube

"They behave well and react directly to the summer temperature, so when the summers get warm, they go right back, summer cools, they move forward make them one of the most reliable substitutes for summer temperature changes. "

And as atmospheric carbon dioxide should rise again in 2019, we can expect more from these warm summers.

"We have not seen anything so pronounced before," Pendleton added.

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