As the planet’s warming rapidly changes the landscape of the Arctic region to the north, scientists have discovered disturbing and alarming signs at the southern end of the planet, especially in one of the ice shelves that protect the so-called “Doomsday glaciers” of Antarctica.
Satellite images taken recently last month, which the researchers presented at the annual meeting of the American Geophysical Union on Monday, show the important ice shelf holding the same Thwaites glacier to the east. West Antarctica – a vital defense against global sea level rise – could be broken within the next three to five years.
Antarctica’s Thwaites Glacier is known as the “Doomsday Glacier”, due to the serious danger it poses in the melting process. It dumped billions of tons of ice into the sea, and its collapse could lead to irreversible changes across the planet.
Glaciers, about the size of Florida or the UK, already account for about 4% of global sea level rise annually, lose about 50 billion tons of ice a year, and are becoming very vulnerable to the gas crisis. Queen. The collapse of the ice shelf could entail the impending collapse of an important Antarctic glacier.
If Thwaites were to collapse, the event could raise sea levels by several feet, putting coastal communities as well as low-lying island states even more at risk, the researchers say.
But Ted Scambos, a glaciologist at the University of Colorado Boulder, and leader of the Thwaites Glacier International Cooperation, says it will be decades before the world sees a real acceleration and sea level rise further.
“What has caught Thwaites’ attention is that the change will come with pretty dramatic, measurable results within the next few decades,” Scambos told CNN.
Currently, the glacier is being held back by an important floating ice shelf.
“The most disturbing thing about these recent results is that it points to the collapse of this ice shelf, the kind of safety band that holds the ice on land,” said Peter Davis, an oceanographer with the National Antarctic Survey. England, told CNN. “If we lose this ice shelf, then glaciers will flow into the ocean faster, contributing to sea level rise.”
Warming seas play an important role in driving the rapid degradation. A 2020 study by the International Thwaites Glacier Collaboration, now leading ongoing studies in Antarctica, shows that the ocean floor is deeper than scientists previously thought, with deep passages that allow warm ocean water to cool melt the underside of the ice.
Observations suggest that the important ice shelf holding the Thwaites together is loosening its grip on underwater mountains, or seams, which act as a reinforcing force against glaciers flowing into the warm ocean pressure. The researchers also found that the so-called “ice tongue” of the Thwaites glacier is now simply an “iceberg cluster”, no longer affecting the stable portion of the eastern ice shelf.
Warm water also threatens the so-called “landing zone,” where the ice meets the seafloor. Davis and his team used hot water to drill holes approaching from the surface of the ice shelf and deep into the oceanic cavity below. In doing so, they discovered that not only was the sea water at the landline warm by polar standards, but it was also saline, preying on the landscape further erosion.
Peter Washam, a research associate at Cornell University who was also involved in the study, said the physical features of the landing area show signs of turbulence, such as warm water, rough ice. The rapids and steep, steep bottoms allow water to rapidly melt the ice sheet from below.
“Over the coming years, we expect the Thwaites landfall in the region to slowly recede above the slope of the seafloor it currently sits on as the warm ocean erodes the underside of the ocean,” Washam told CNN. it. His team used an underwater vehicle called the Icefin, which makes it easier to study the ice and water around and below the ice shelves.
The bottom line, according to Davis, is that Antarctica’s Thwaites Glacier is in rapid decline. Warm ocean water is slowly removing the ice below, causing the water to flow faster, fracturing more ice and making the danger of imminent collapse closer.
“From the satellite data, we see these large cracks spreading across the surface of the ice shelf, essentially weakening the structure of the ice; a bit like a windshield crack,” he said. “It’s slowly spreading across the ice shelf and it will eventually break apart into different pieces.”
While this process is extremely slow and the real effects won’t be felt until several decades later, it’s nearly impossible to stop it, Scambos said.
“This is a geological process, but it happens on a scale that is almost a lifetime,” he said. “As a disaster for people alive today, it moves incredibly slowly. The best course of action is to try to slow down the forces that are pushing the ice in this direction.”
And as ramifications of the climate crisis spread across the globe, researchers say expanding scientific research to understand changes in both the Arctic and Antarctic regions is crucial to planning. planning mitigation strategies such as coastal defense in vulnerable communities.
“We can’t really do anything to stop this from happening,” other than slow it down, Davis said. “The way we’ve been doing with our carbon footprint so far has caused these changes – and we’re essentially suffering the consequences of what we’ve been putting off over the past few decades. , if not longer.”
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