Glaciers all over Antarctic have problems like ice there it melts quickly. There is no Antarctic glacier whose fate is more important to our future than the Thwaites glacier, and new research shows that things are not looking good for him.
Researchers have known the fact that the Thwaites glacier has problems due to the invasion of hot water, but would never have actually analyzed the data under the glacier’s floating ice platform – until now. A new study published in Science Advances on Friday presents the first direct observations about what is happening under the famous ice shelf, including the temperature and salinity of the water flowing under it, as well as the power of the current.
What they found is quite worrying. The authors explain that the supply of hot water to the base of the glacier is higher than scientists previously believed, which means it’s even more unstable than I thought. Given that it is often called the “glacier of the day of judgment,” it is particularly bad.
Thwaites Glacier is a large, vast piece of ice that flows from the ice path in western Antarctica to Pine Island Bay, part of the Amundsen Sea. The 119,300-square-mile (192,000-square-mile) ice shelf disappears faster than any other in the region, largely due to water flowing beneath it and depleting at its base. If it collapses completely, it could have a devastating effect on global sea level rise.
The new study is based on field observations from 2019, when a team of two dozen scientists sent a self-employed orange submarine called A fugit sub Thwaites. For 13 hours, the underwater vehicle traveled around two deep gutters under the glacier, which carry hot water to it. As it did, the vehicle captured data showing that hot water – warm for a glacier, up to 33.89 degrees Fahrenheit (1.05 degrees Celsius) – revolves around the glacier’s crucial “fixing points”. or the points of contact where the ice shelf meets the bedrock that holds it in place. This warm water melts these crucial qualities, making room for cracks and ice gutters that can make the shelf even more unstable.
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“The concern is that this water comes in direct contact with the bottom of the ice shelf at the point where the ice tongue and the shallow seabed meet,” said Alastair Graham, an associate professor of geological oceanography at the University of South Florida. , who was on the glacier research expedition, wrote in an email. “This is the last fortress for the Thwaites and once it comes off the seabed right in front of it, there is nothing else to hold the ice shelf on. This hot water also mixes in and around the ground line, deep in the cavity, which means that the glacier is also attacked at its feet, where it rests on a solid stone. ”
Discovering hot water confirms previous concerns from a separate project, in which another group of 100 scientists drilled a 2,000-meter hole in the glacier.
“This study fills the critical gaps in our knowledge in this area and will undoubtedly allow major progress in shaping this system and thus improved projections,” said David Holland, a glaciologist at New York University who worked on the previous study. most recently, wrote in an email.
As the submarine moved around one of the gutters, it also captured data showing water with low salinity in the area of 1,044 meters (3,444 feet) under the ice platform. The level of salinity he showed matches that of neighboring Pine Island Bay. Scientists previously believed that this part of the glacier was protected from the currents of the bay by a thick underwater ridge. But they seem to have been wrong – the findings indicate that it flows freely in the gutter. This is more closely linked to the fate of golf than current climate models consider.
We don’t just have to worry about the warm waters of Pine Island Bay. Using the submarine’s readings, the authors also traced the channels along which hot water is transported to the Thwaites Glacier. They found that more hot water was also flowing along the continental shelf.
“Thwaites is really being attacked by the ocean from all sides,” Graham said.
All this has very serious consequences for those who live along the coast. The collapse of the Thwaites Glacier would raise sea levels by 0.5 to 0.9 meters and could also trigger an even worse chain of events. as it could initiate the collapse of another nearby endangered ice shelf, Pine Island Glacier. Together, these shelves act as a braking mechanism on the ground ice that, if released into open water, it could push the seas up to 10 feet (3.1 meters), overwhelming coastal cities around the world.
In the last four decades, Graham explained, satellite data showed that the glacier flows into the ocean much faster. Sure, it fills up some of it when fresh snow falls and compacts into new ice, but that doesn’t happen fast enough to make up for its losses.
To learn more about this process, scientists are trying to learn as much as they can about the glacier. Sending a submarine under it marks a big, innovative step. But there is still a lot of uncertainty about how fast the collapse is approaching.
The study illustrates the importance of climate adaptation measures, including weighing the potential benefits of communities retreat away from the ribs. This is especially true because Graham said it is not entirely clear whether or not the death of the Thwaites can be prevented.
“You may (and I emphasize you may) have already reached a point where there is no turning back for the Thwaites, no matter what we, as humans, do for our climate,” Graham said.
Graham knows how scary this is first hand because he lives on the coast of the Gulf of Florida. But not everything is lost.
– May to be physical mechanisms that we have not yet discovered, which could help the Thwaites to stabilize and the “final day” may never come, “he said.