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Arctic landscapes, hidden for more than 40,000 years, appear



Climate change pulls back the curtain and reveals an arctic landscape that is not visible to the Sun for 40,000 years or more.

Baffin Island is a rocky, frozen miracle located in the Arctic Circle between Greenland and the northern coast of Canada. With its deep fjords and ancient glaciers, this is the perfect place to study the ice age models.

Geologist and paleoclimatologist Gifford Miller of the University of Colorado Boulder has traveled here almost every summer for the past 40 years, and the changes he has found are worrying.

Today the Arctic is warming two to three times faster than the rest of the world. If the trend continues, Miller thinks it's only a matter of time before all of Bafin Island's glaciers disappear altogether.

"Unlike the biology that has spent the last three billion years in developing schemes to avoid the effects of climate change, the glaciers have no survival strategy," Miller said, "They behave well, react directly If summer is warm, they immediately retreat, if the summer is cool, they are advancing, making them one of the most reliable powers of attorney for summer temperature changes. "

Miller and his team are walking around the edges of these fast-melting glaciers and discovered ancient moss and lichens kept under an ice blanket for millennia.

Now, with climate change, more and more edges of the cover, some of these ancient plants are beginning to wake up from their natural sleep. "The strange thing in these mosses is that many of them can just start to grow again so they are the closest to the zombie I know, the living dead," said Miller in a short film about [1

9659002] In August last year, researchers collected 48 samples of vegetation from the edges of 30 different Baffin ice caps, as well as some samples of nearby quartz.

Using radiocarbon dating, researchers believe that these plants have the most conservative calculations returning us to the last ice age when the average temperatures are colder than they are today, and woolly mammoths have still been hunted by humans. This is likely when the plateau on the island of the tundra was buried by the ice we see today, wrapping its plants in a tomb that should not have been opened so soon.

But today, thanks mainly to human activity, the heat we are experiencing is enough to reverse thousands of years of natural change. Compared to the Arctic ice core temperature data, the results show that this century is the warmest that the region has experienced for about 115,000 years.

These are unprecedented changes located far beyond the scope of natural variability and touching almost every corner of Baffin Island.

"You usually expect to see different plant ages in different topographical conditions," says lead author Simon. Pendlton, an expert in glacial geology at the University of Colorado, Boulder.

"A high altitude location can keep the ice longer, for example, but the warming is so high that everything melts everywhere." If nothing changes, the authors predict that over the next few centuries the island can be completely free.

This study was published in Nature Communications .


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