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Arctic landscapes that have been hidden for more than 40,000 years are emerging



Climate change is pulling back the curtain and exposing an Arctic landscape that has not been seen by the sun for 40,000 years or more.

Baffin Island is a rocky, frozen wonderland in the Arctic Circle between Greenland and the north coast of Canada. With its deep fjords and ancient glaciers, it is the perfect place to study the patterns of the Ice Age.

Geologist and paleoclimatologist Gifford Miller of the University of Colorado Boulder has been traveling here almost every summer for nearly 40 years, and the changes he has uncovered are disturbing.

Today, the Arctic warms two to three times faster than the rest of the world. If the trend continues, Miller believes it's only a matter of time before all the glaciers on Baffin Island have completely disappeared.

"Unlike biology, which has developed schemes over the last three billion years to avoid the effects of climate change, glaciers have no survival strategy," explains Miller.

"They behave well and react directly to the summer temperature, so when the summers get warm, they recede immediately, and when the summers cool, they move forward, making them one of the most reliable alternates in the summer temperature." [1

9659002] Miller and his team walked along the edges of these fast-melting glaciers, uncovering ancient moss and lichen that had been stored under an icy blanket for millennia.

Now, however, climate change has stolen more and more cover Some of these ancient plants are awakening from their natural slumber.

"The strange thing about these mosses is that many of them are just about to grow again, so they're closest to a zombie I know, the living dead," Miller said in a short film about the topic.

In August of last year, researchers collected 48 vegetation samples from the edges of 30 different Baffin ice caps as well as some samples of nearby quartz.

Using radiocarbon dating, the researchers found that these plants have been frozen at least for the last 40,000 years and possibly up to 120,000 years in time.

The most conservative estimates lead us back to the last Ice Age, when the average temperatures were colder than today, and the woolly mammoths were still hunted by humans. This is probably the case when the island's tundra plateau was buried by the ice we see today and its plants were in a grave that was not to be opened soon.

But nowadays, mainly thanks to human activity, the heat we have experience is enough to reverse thousands of years of natural change. Compared with the temperature data from Arctic ice cores, the results suggest that this century is the warmest that the region has experienced for some 115,000 years.

These are unprecedented changes that are far outside of natural variability and touch almost every corner of Baffin Island.

"Typically, you expect different plant ages under different topographical conditions," says lead author Simon Pendleton, an expert in glacial geology at the University of Colorado Boulder.

"A high could, for example, stick to its ice for longer, but the warming is so great that everything melts everywhere." [19659002] "We have not seen anything so pronounced before."

If nothing changes, the authors predict that the island could be completely free of all ice over the next few centuries.

This study was published in Nature Communications .


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