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Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ The receding ice exposes an arctic landscape unseen for 120,000 years

The receding ice exposes an arctic landscape unseen for 120,000 years



The retreat of Arctic glaciers reveals landscapes that have not seen the sun for nearly 1

20,000 years.

These rocky sights were probably covered with ice from the Emirate's time, when the average temperatures were up to 3.6 degrees Fahrenheit (2 degrees Celsius) warmer than current, and the sea levels up to 30 feet ( 9 meters) higher.

"The last century of warmth is probably greater than every century before 120,000 years ago," said study leader Simon Pendoll, Ph.D. student at the University of Colorado, the Institute of Arctic and Alpine Studies at Boulder. Canned Plants

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Pendleton and his colleagues walked through these ancient landscapes while sampling on the island of Bafin, Canada, the island is surrounded by dramatic fjords, but its interior is dominated by high elevations, relatively flat planes the tundra [19659005] These tundra plains are covered with thin ice caps, and since the landscape is so flat, ice caps do not flow and slide like typical glaciers, says Pendleton, instead they just sit on rocks and soil, keeping everything under

What is preserved are the small arctic plants and mosses that were last when the ice was embraced by the earth.While the ice melts, Pendleton reveals this ancient, delicate vegetation. Wind and water destroy long-lost plants within months, but if researchers can get to them first, they can use radiocarbon dating to determine the age of vegetation.

Radiocarbon dating measures the levels of slowly decomposing carbon, carbon-14 isotope. (Carbon-14 has eight neutrons in its core, not six as ordinary carbon.) Since scientists know how fast carbon-14 decomposes – and plants take carbon-14 through photosynthesis – they can use the amount of an isotope in an organic sample to determine your age.

Pendleton and his colleagues took 124 samples from 30 locations around the eastern island of Baffin, about 1 meter from the edge of the modern ice cap, the area most recently revealed by the melt where the remains

They found that all of their samples were were at least as old as the oldest age that radiocarbon dating can find: 40,000 years. This is a direct indication that plants have been on ice for at least so long, researchers said in Nature Communications.

Visible Change

Researchers are able to support these vegetation measurements with near-scale minerals, which also suggest at least 40,000 years of continuous ice coverage. And it's almost certain that Bayfing Island has been buried on ice for a much longer time, Pendleton said. Forty thousand years ago, the world was in the middle of the last Ice Age. If the temperatures are as hot as today's, to melt the ice that lasts for so long, the last period to find those in the Arctic is nearly 120,000 years ago, Pendleton said. Perhaps some of today's landscapes have been buried since this warm interplanetary period. "We know that dramatic changes happen and will continue to happen, but I do not know that we expected to find evidence that we are now seeing landscapes and temperatures similar to this. "The changes to Bafin Island are undeniable even with the naked eye," said Pendleton, "the research team took samples on the island in 2005, 2013, 2014 and 2015." Year to year, Pendleton said, the retreat of the ice is obvious Researchers will use GPS to determine their previous point "Somewhere," said Pendleton, "they will be the length of a football field at the new end of the ice."

"To be able to stand there and see that the change "I do not have a good word," Pendleton said. "Somehow it's breathtaking."

Originally posted on Live Science .


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