Glaciers all about- Antarctica are in trouble like ice cream there melts quicklyThere is no Antarctic glacier whose fate has more implications for our future than the Thwaites Glacier, and new research shows it doesn’t look right.
Researchers have known that the Thwaites Glacier is in trouble due to intrusive warm water, but they had never really analyzed data under the glacier’s floating ice shelf until now. A new study published in Science Advances on Friday presents the first-ever direct observations of what is happening under the infamous ice shelf, including the temperature and salinity of the water flowing beneath it, as well as the strength of the current.
What they found is quite disturbing. The authors explain that the supply of warm water to the base of the glacier exceeds scientists previously believed, which means it’s even more unstable than we thought. Given that it is often referred to as the “ doomsday, ” that is particularly ominous.
Thwaites Glacier a wide, huge piece of ice that flows from the West Antarctic Ice Sheet to Pine Island Bay, part of the Amundsen Sea. The 192,000 square kilometers (119,300 square miles) ice shelf is disappearing faster than any other in the region, largely because of the water circulating underneath and wearing away at the 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 an autonomous orange submarine called Ran down Thwaites. For 13 hours, the underwater vehicle drove around two deep troughs under the glacier that lead warm water to it. While it did, the vehicle recorded data showing that warm water – warm in front of a glacier, up to 33.89 degrees Fahrenheit (1.05 degrees Celsius) – swirls around the glacier’s crucial ‘tie-down points’, or the contact points where the ice shelf meet the foundation that holds it in place. This warm water melts away these crucial holds, leaving room for cracks and dips in ice that can make the shelf all the more unstable.
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“The concern is that this water will come into direct contact with the bottom of the ice shelf at the point where the ice tongue and the shallow seabed meet,” said Alastair Graham, associate professor of geological oceanography at the University of Southern Florida. the author, who was on a research expedition to the glacier, wrote in an email. “This is the last stronghold for Thwaites and when it comes off the bottom of the sea at the very front, there is nothing else for the ice shelf to hold on to. That warm water is also likely to mix in and around the earth line, deep in the cavity, and that means the glacier is also being attacked at its feet where it rests on solid rocks. “
The discovery of hot water confirms previous concerns from a separate project in which another group of 100 scientists drilled a 600-meter hole in the glacier.
“This study fills crucial gaps in our knowledge in this area and will undoubtedly allow great advances in modeling this system, and thus improved projections,” David Holland, a New York University glaciologist who worked on the previous study, but not the newer, wrote in an email.
As the submarine moved around one of the troughs, it also collected data from low-salinity water in the area 1050 meters below the ice shelf. That salinity matched 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 it seems they were wrong – the findings indicate that it flows freely into the trough. This links its fate more closely to the bay than current climate models.
It’s not just the advancing warm waters of Pine Island Bay that we should be concerned about as well. Using the submarine’s measurements, the authors also mapped the channels along which warm water is transported to the Thwaites Glacier. They found that more warm water is also flowing in along the continental shelf
“Thwaites is really under attack from all sides by the ocean,” said Graham.
All this has very serious consequences for those living along the coast. The Thwaites Glacier collapse would raise sea levels by 1.5 to 3 feet (0.5 to 0.9 meters) and could also trigger an even worse chain of events because it was the collapse of another nearby threatened ice shelf, the Pine Island GlacierTogether these boards act as a braking mechanism on land ice that if released into open water, it could float out to sea 10 feet (3.1 meters), stunning coastal cities around the world.
Over the past four decades, Graham explained, satellite data has shown that the glacier flows into the ocean much faster. Sure, it replenishes some of it when fresh snow falls and is compressed into new ice, but that doesn’t happen fast enough to make up for the losses.
To learn more about this process, scientists are trying to learn as much as possible about the glacier. Sending a submarine underneath marks a major, groundbreaking step. But there is still a lot of uncertainty about how quickly it will end in collapse.
The study illustrates the importance of climate adaptation measures, including weighing the potential benefits of having communities retreat from the shoresThat’s especially true because Graham said it’s not entirely clear whether or not the Thwaites’ demise is preventable.
“We may have (and I may emphasize it) already reached and passed a point where there is really no going for Thwaites, no matter what we as humans do with our climate,” Graham.
Graham knows how scary this is firsthand considering he lives on the Gulf Coast of Florida. But all is not lost.
“There can are physical mechanisms that we have yet to discover that could help Thwaites stabilize and ‘doomsday’ may never come, ”he said.