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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/ Ancient plants reveal Arctic summers that were not hot for 115,000 years

Ancient plants reveal Arctic summers that were not hot for 115,000 years



The glaciers and ice caps on Baffin Island in Arctic Canada have receded dramatically in recent decades, revealing ancient landscapes that were probably covered with ice for about 1
15,000 years.
Photo: Gifford Miller, University of Colorado Boulder / INSTAAR The latest sign of how much the Arctic is wrapped is: moss that has not seen the light of day in at least 40,000 years collapses from the ice caps of the Canadian Bafffin Island, thanks to the ever sweeter summer. Building on this and other evidence, the research published in Nature Communications on Friday suggests that the summer of the Canadian Arctic was not so warm in 115,000 years or more.

Even in the wilderness of statistics about how climate change turns the Arctic, this stands out.

"This study shows that wow, we are displaying landscapes that are 120,000 years old," said lead author Simon Pentton, of the University of Colorado's Arctic and Alpine Research Institute. "Our last century of warmth is probably greater than any century over the past 120,000 years."

Preserved ancient moss collected from the field of the retreating ice cap on Baffin Island.
In order to reach this conclusion, Pendleton and his colleagues relied on Baffin Island's ice and the strange geographic features that allowed him to reveal his secrets. The island is home to deep fjords and tall fabrics, the last of which is covered with ice caps. Ice hats are huge pieces of ice, like glaciers, but there is one major difference. Where the glaciers flow and ground on the ground beneath them, the ice caps are static. This means that everything that is on the ground when they are formed is retained instead of being ground to dust.

For centuries, ice has occupied plateaus and walls on Bafin Island. In some summers it would melt, but in general the low temperatures and the snow kept things in balance. Now, climate change has disturbed this equilibrium, causing the Arctic to warm up twice as fast as the rest of the world. This has led to more summer melt, which reveals moss and mist in the periphery of ice caps. Pendelton and others collected samples of about 30 ice caps and conducted radiocarbon dating to determine their age. The findings show that mosses are at least 40,000 years old (and on the wild some mosses have been returned to the labs and returned to life as an Arctic zombie).

is near the end of the story that you can explore with radiocarbon dating. It also happens to hit the middle of the ice age. This made Pendleton and his colleagues look for other records, including nearby ice measurements from Greenland. By cross-referencing the plants, they show that the area has been covered with ice for over 40,000 years, and the summer of our new climate is probably softer than anything in about 115,000-120,000 years. step back even further, they can expose even more ancient landscapes. By refining their measurements, scientists can then predict how the Arctic will look, as climate change continues to change it. Pendleton said even without radiocarbon dating, it is clear how quickly Baffin Island moves into a new state. Every year changes are becoming more visible with the naked eye.

"In order for you to see and walk on the ice hat and find out that we are in a moment that exposes landscapes that have not seen sunlight for 120,000 years, it has a profound impact," he said.


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