Greens instead of ice. Ice from a secret mission has revealed new details about Greenland’s history
[ad_1]
An ice core from a secret Cold War military mission shows that most of Greenland was green 416,000 years ago, writes Sci Tech Daily. A recent study in the journal Science suggests that most of the island was tundra. Maybe covered in trees and roaming mammoths. Before that, geologists believed that the ice sheet existed for most of the last 2.5 million years. Instead, moderate warming from 424,000 to 374,000 years ago led to dramatic melting. Then the sea level rose by at least 1.5 meters. This was despite the fact that the level of carbon dioxide, which traps heat, was half that of today. Therefore, the Greenland ice sheet may be much more sensitive to climate change than previously thought. Photo: jele76/Depositphotos.com Such conclusions were reached by scientists from the University of Vermont (UVM), the University of Utah and fourteen other institutions thanks to ice collected at the secret US Army base Camp Century in the 1960s. Then the military drilled 1,390 m of ice to get sediment with soil and stones from the depths. After that, it was stored in the freezer for decades. It wasn’t until 2017 that the sediment was reopened and revealed to contain leaves and moss, possibly from a boreal forest. This study provided direct evidence that the sediment directly beneath the ice sheet was deposited by flowing water in an ice-free environment during a period of moderate warming called marine isotopic stage 11, between 424,000 and 374,000 years ago. “This is really the first hard evidence that most of the Greenland ice sheet disappeared when it warmed,” said University of Vermont scientist Paul Bierman, who led the new study. In addition, the results affect the understanding of the future of the planet. As sea level rise is linked to the melting of the Greenland ice sheet, every coastal region in the world is at risk. “If we melt just part of the Greenland ice sheet, sea levels will rise dramatically. When we model melting rates and the response to high carbon dioxide, we’re looking at meters of sea level rise, probably tens of meters. And then look at the height of New York, Boston, Miami, Amsterdam. Look at India and Africa – most of the global population is near sea level,” says Tammy Rittenor of Utah. We will remind you that June 2023 became the hottest in the entire history of observations. At the same time, the world is experiencing the hottest week on record. Read also: NASA scientists predict an increase in floods and droughts in the world due to climate change
[ad_2]
Original Source Link
