![]() ![]() ![]() There have been a spate of reports in recent weeks pointing towards a possible change in the shape of the Antarctic peninsula due to the breaking away of chunks of ice from the mainland. Exactly how quickly and how extensively Thwaites Glacier may collapse is dependent on a complex interaction of ice, sea, and land.īut scientists say it does look likely that the floating portion of the ice will fail in the near future.WHEN vegetation sprouts in a desert, it is a good sign but when the ice in the Arctic and the Antarctic begins to turn green, there is something terribly wrong. It is this scenario that is likely to massively contribute to rising sea levels. It will also be in greater contact with the relatively warm waters of the Amundsen Sea, accelerating melting. With the waterborne portion of the glacier breaking up, scientists estimate that the landlocked ice will begin to flow three times faster than it currently is. The real concern is that the floating ice is currently holding back a large portion of the Thwaites Glacier that sits on land. That’s because this portion of the Thwaites glacier is already floating, so the weight of that ice is already displacing the same amount of water that will be unlocked when the icebergs melt. But those icebergs won’t make any difference to global sea levels themselves. If that happens, the glacier will discharge thousands of massive icebergs into the Southern Ocean, where they may present a hazard to shipping. What would happen if the ice sheet were to shatter? Erin Pettit, a glaciologist at Oregon State University, compares this to how just a few cracks in a car windshield can spiderweb across the entire surface and then suddenly cause the whole glass panel to dramatically shatter. ![]() Scientists say these fractures indicate that the floating eastern portion of the glacier is in danger of catastrophic collapse within three to five years. The researchers believe that as warming seas undercut the floating portion of the glacier from below, the ice becomes more susceptible to flexing from tidal variations, and that this flexing may be what is causing the cracking. It is these cracks that are causing sudden alarm among scientists, who have previously seen hints that the eastern portion of the glacier might be unstable but have been surprised to see the speed at which these fractures are advancing. In addition, satellite images taken over the past two years, including as recently as November, have shown the appearance of rapidly lengthening large fractures in the portion of the eastern glacier that are sitting atop sea water. This mountaintop acts like a doorstop, blocking the glacier’s forward progress.Įarlier this year, researchers demonstrated that the Thwaites’ eastern ice sheet is becoming unstuck from its mountaintop brace. Scientists have shown that one reason for this is that floating ice from the glacier collides with an undersea mountaintop about 25 miles offshore. While two-thirds of the Thwaites Glacier is relatively fast-flowing, the eastern portion has been moving much more slowly. Temperatures have been rising fast globally. That’s how the Thwaites got its Doomsday nickname. A sea level rise of this nature would threaten the lives of millions of people globally. That’s enough to swamp portions of the Thai capital Bangkok, as well as New Orleans, and cause more frequent flooding in places like New York City. It sheds about 50 billion tons of ice per year, which already contributes to about 4% of annual global sea level rise.īut if the Thwaites Glacier were to melt entirely, scientists have estimated it would drive sea levels up by more than 25 inches. It abuts the West Antarctic Ice Sheet to its east, and the Amundsen Sea to its West. ![]() It sits on top of bedrock at the western edge of Antarctica. It is a giant sheet of ice, the widest glacier on the planet, and about the size of the U.S. The Doomsday Glacier’s formal name is the Thwaites Glacier. Here’s what you need to know: What is the Doomsday Glacier? It is also possible that efforts to check global warming could still prevent the worst from happening. So we have some time to potentially prepare. The good news, if there is any, is that the shattering of the ice, which is currently bracing a key portion of the Thwaites Glacier, won’t likely occur for another three to five years, and any rapid acceleration in the pace of sea level rise would happen only in the years and decades after that. “What we’re seeing already is enough to be worried about,” Anna Crawford, a glaciologist at the University of St. ![]()
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