Satellite video shows ice shelf holding Pine Island Glacier in Antarctica back from the ocean is breaking up much faster than previously thought
An important Antarctic glacier is looking more vulnerable as satellite images show that the ice shelf that kept it from falling into the ocean is breaking apart much faster than previously thought and creating giant icebergs, a new study finds. stated in.
Pine Island Glacier ice shelf loss accelerated in 2017, causing scientists to worry that glacier collapse with climate change may be several centuries quicker than predicted. The floating ice shelf acts like a cork in a bottle for a rapidly melting glacier and prevents its very large ice mass from flowing into the ocean.
The ice shelf has retreated 12 miles (20 kilometers) between 2017 and 2020, according to a study in Friday’s Science Advances. And the collapsing shelf was caught on time-lapse video from a European satellite that takes pictures every six days.
Study lead author Ian Juffine, a glaciologist at the University of Washington, said, “You can see stuff just tearing up. So it looks like the speed-up itself is weakening the glacier. … And by now we’re probably lost.” 20% of the main shelf is gone.”
Between 2017 and 2020, three major breakaway events occurred, creating an iceberg more than 5 miles (8 kilometers) long and 22 miles (36 kilometers) wide, which then split into lots of smaller pieces, Juffine said. There have also been several minor breakups.
“It’s not at all inconceivable that the entire shelf could give way and be gone within a few years,” Joffin said. “I would say it’s a long shot, but not a very long shot.”
Joffin tracked two points on the main glacier and found they were moving 12% faster toward the ocean starting in 2017.
“So that means 12% more ice from Pine Island is going into the ocean that wasn’t there before,” he said.
Pine Island holds 180 trillion tons of ice – the equivalent of 1.6 feet (half a meter) of sea level rise – and is responsible for nearly a quarter of the continent’s ice loss.
“Pine Island and Thwaites are our biggest concern now because they are separating and then the rest of West Antarctica will follow almost according to all models,” said University of California Irvine ice scientist Isabella Velikogna, who was not part of the study.
While the loss of ice is part of climate change, there was no unusual additional warming in the region that triggered this acceleration, Joffin said.
“These science results continue to highlight the vulnerability of Antarctica, a major reservoir for potential sea level rise,” said National Snow and Ice Data Scientist Twyla Moon. “Over and over again, other research has confirmed that how Antarctica develops in the future will depend on human greenhouse gas emissions.”
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