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A new NASA-funded study warns that, due to man-made global warming, the gigantic Thwaites Glacier, West Antarctic, is likely to reach a tipping point that could raise the global sea level by around 20 inches.
"After reaching the tipping point, Thwaites Glacier could lose all of its ice in a 150-year period.This would give a rise in sea level of about half a meter (1.64 feet). "
-Hélène Seroussi, NASA
The study, published Monday in the newspaper the Proceedings of the National Academy of Sciences, was conducted by researchers at the Georgia Institute of Technology, NASA's Reaction Propulsion Laboratory and the University of Washington.
Although this team focused on the Thwaites Glacier – which is about the size of Florida or Britain – several others have alarmed the alarm about how quickly the ice disappears in Antarctica, including including a May study that reveals that the continent's ice caps are thinning five times faster than in the 1990s.
In a statement released Monday, Georgia Tech explained that researchers have discovered that "the instability hidden in the Antarctic ice would likely accelerate its flow into the ocean and would raise sea levels at a faster rate provided that".
According to the National Science Foundation, five closely monitored Antarctic glaciers have doubled their rate of ice loss. At least one, Thwaites Glacier, designed for the new study, may succumb to this instability, an unstable process that quickly propels ice into the ocean.
The Thwaites Glacier is often called "one of the most dangerous glaciers in the world" because of its potential contributions to the rise in sea level. Common dreams reported in January, NASA scientists recently discovered a Deep cave of 1000 feet in the glacier large enough to have retained about 14 billion tonnes of ice before it melted, which has heightened concerns about the future of the glacier.
The researchers behind the new study have not been able to predict exactly how much ice the Thwaites Glacier will lose in the next 50 to 800 years, "because of unpredictable fluctuations in climate and need more data ", but they took into account the instability in 500 ice flow simulations for the glacier, which" together showed the eventual triggering of instability ", according to the Georgia Tech statement.
"If you trigger this instability, you do not need to keep forcing the ice layer by raising the temperatures.It will continue to work on its own, and that's the concern," he said. lead author Alex Robel, assistant professor at Georgia Tech's School. earth sciences and the atmosphere. However, he added, "the climatic variations will always be important after this tipping point, because they will determine the speed at which the ice will move".
The simulations lasted several centuries, as is often the case for studies on sea level rise. The models suggest that the glacier could reach the tipping point "in the next 200 to 600 years, "said NASA co-author and scientist Hélène Seroussi. "It depends on the bedrock topography under the ice, and we do not know it in detail yet."
"There is nearly eight times more ice in the Antarctic Ice Sheet than in the Greenland Ice Cap and 50 times more than in all the mountain glaciers in the world."
-Alex Robel, Georgia Tech
"After reaching the tipping point, Thwaites Glacier could lose all its ice in 150 years," Seroussi said. "That would make sea level rise of about half a meter (1.64 feet)."
Experts also alerted about the speed with which ice melted in Greenland and the Arctic, but Antarctica is of particular concern because, as Robel pointed out, "there are nearly eight times more ice in the Antarctic ice cap than in Greenland ice and 50 times more than in all the mountain glaciers of the world ".
The researchers recognized the need for further study, but also stressed the importance of preparing for the rising seas, which is increasingly endangering island nations and coastal communities.
"You want to put in place a critical infrastructure to withstand the upper limit of potential sea level scenarios in a hundred years," said Robel. "This can mean building your water treatment plants and your nuclear reactors in the worst case, which could be a sea-level rise of only two to three feet from the Thwaites Glacier, which is the only way to do so. so is a huge difference. "
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