The key to seeing exactly how bad conditions are on the glacier would require going to the main trunk and looking at the melting from below. And they also found staircase-like steps, those crevasses, in parts of the more stable eastern side where the break-up is far faster and worse. Researchers couldn't safely land a plane and drill a hole in the ice in the main trunk, which is breaking up much faster. When ice is on ground as part of the glacier it isn't part of sea rise, but when it breaks off land and then goes onto water it adds to the overall water level by displacement, just as ice added to a glass of water raises water level.Īnd more bad news: This is from the eastern, larger and more stable part of Thwaites. The more the glacier breaks up or retreats, the more ice floats in water. ![]() Pennsylvania State University glaciologist Richard Alley, who also wasn't part of the studies, said the new work "gives us an important look at processes affecting the crevasses that might eventually break and cause loss of much of the ice shelf."ĭavis said the melting isn't nearly the problem at Thwaites that glacier retreat is. "I am definitely expecting the rapid change to continue and accelerate over the next few years." "Thwaites is a rapidly changing system, much more rapidly changing than when we started this work five years ago and even since we were in the field three years ago," said Oregon State University ice researcher Erin Pettit, who wasn't part of either study. ![]() The melting of Thwaites is dominated by what's happening underneath, where warmer water nibbles at the bottom, something called basal melting, said Peter Davis, an oceanographer at British Antarctic Survey who is a lead author of one of the studies. The Florida-sized glacier has gotten the nickname the "Doomsday Glacier" because of how much ice it has and how much seas could rise if it all melts - more than 2 feet (65 centimeters), though that's expected take hundreds of years. The work comes out of a massive $50 million multi-year international research effort to better understand the widest glacier in the world. "It's eventual mode of failure may be through falling apart." That fracturing "potentially accelerates the overall demise of that ice shelf," said Paul Cutler, the Thwaites program director for the National Science Foundation who returned from the ice last week. It shatters," said Schmidt, lead author of one of two studies in Wednesday's journal Nature. "That's how the glacier is falling apart. But with the robot named Icefin lowered down a slender 1,925-foot (587-meter) hole, they saw how important crevasses are in the fracturing of the ice, which takes the heaviest toll on the glacier, even more than melting. Using a 13-foot pencil-shaped robot that swam under the grounding line where ice first juts over the sea, scientists saw a shimmery critical point in Thwaites' chaotic breakup, "where it's melting so quickly there, there's just material streaming out of the glacier," said robot creator and polar scientist Britney Schmidt of Cornell University.īefore, scientists had no observations from this critical but hard-to-reach point on Thwaites. Scientists got their first up-close look at what's eating away part of Antarctica's Thwaites ice shelf, nicknamed the Doomsday Glacier because of its massive melt and sea rise potential, and it's both good and bad news. ![]() The pencil-shaped robot is giving scientists their first look at the forces eating away at the Thwaites glacier. Scientists had predicted some chunks could break away from A68A as it approached the island, and more breakage is possible.Ī68A broke off from the Antarctic peninsula in 2017.A robot nicknamed Icefin operates under the sea ice near McMurdo Station in Antarctica in 2020. An estimate of A68D’s size was unavailable. Scientists don’t yet know if it will follow the same path, or become lodged somewhere else on the shelf. The new smaller iceberg, A68D, is moving further away from the original. “All of those things can still happen, nothing has changed in that regard,” Tarling said. That means it could still cause an environmental disaster for local wildlife, but along the island’s eastern coast rather than the south-west. It appeared, however, to be heading south-east towards another current that would probably carry it away from the shelf edge before sweeping it back around toward the island’s eastern shelf area. They were also worried that it might block penguins making their way into the sea for food.Īs of Friday, the original A68A iceberg was about 50km (31 miles) from the island’s west coast. Researchers feared that, as the iceberg closed in on the wildlife-rich island, it could grind into the seabed, disrupting underwater ecosystems.
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