Home Glaciers An ‘apocalyptic glacier’ in Antarctica could raise sea levels by 2 feet

An ‘apocalyptic glacier’ in Antarctica could raise sea levels by 2 feet

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  • The Thwaites Glacier in Antarctica, which is about the size of Florida, continued to retreat, earning it the nickname “Doomsday Glacier”.
  • Scientists believe its rate of retreat may be accelerating after discovering that it once retreated faster than it does today.
  • The collapse of the Thwaites Glacier could lead to an overall sea level rise of more than two feet.

    Giving the Thwaites Glacier in West Antarctica, one of the largest glaciers in the world, the nickname “glacier of the apocalypse”, does not inspire much confidence in its ability to remain a body of ice dense. A study published Monday in the magazine nature geoscience instills even less confidence, with data showing the glacier could accelerate its rate of retreat at any moment, leading to a collapse that could raise global sea levels by more than two feet.

    “Just a little kick to Thwaites could lead to a big response,” said Ali Graham, a marine scientist at the University of Florida and the study’s lead author. Press release.

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    A multinational research team used the bright orange Rán robotic vehicle loaded with imaging sensors to map an area of ​​the seafloor in front of the glacier that was roughly the size of Houston. It was the first time in history that the front of the glacier was accessed.

    “It was truly a once-in-a-lifetime mission,” Graham said in the release, noting that the team wants to sample seafloor sediments to more accurately date the ridge-like features created by the movement of the glaciers. “But the ice closed in on us pretty quickly and we had to leave before we could do that on this expedition.”

    Calling the data beautiful, if not disturbing, Graham mapped a critical area of ​​the seabed ahead of the glacier in high resolution, learning that Thwaites, at some point in the last 200 years, spanning less than six months, is retreating at a rate of more than 2.1 km per year, twice the documented rate observed in satellite images between 2011 and 2019. “Our results suggest that very rapid retreat pulses have occurred at Thwaites Glacier during the past two centuries, and possibly as recently as the mid-1920se century,” says Graham.

    “Thwaites is really holding today by its fingernails, and we should expect to see big changes on small time scales in the future – even from year to year – once the glacier retreats to the beyond a shallow ridge in its bed,” Robert Larter, a British Antarctic Survey marine geophysicist and co-author of the study, said in the statement.

    To understand Thwaites’ past retreat, the team analyzed submerged rib-like formations about half a mile below the polar ocean. Figuring in the area’s tidal cycle, as predicted by computer models, they determined that a coast was forming every day. “It’s like looking at a tide gauge at the bottom of the sea,” says Graham. “It’s truly mind-blowing how beautiful the data is.”

    A side scan shows the peaks detected by Ran.

    Image credit: Ali Graham

    The effort is part of a five-year project to use the geological record of the seabed in front of Thwaites to reconstruct the history of the glacier and study how it reacted to the atmosphere and the ocean.

    Computer modeling warns that Thwaites could lose ice more rapidly over the next few decades, leading to a significant rise in sea level. The discovery of sustained pulses of rapid retreat in the glacier’s history leads scientists to believe that another occurrence of this movement could happen again.

    “Similar pulses of rapid retreat are likely to occur in the near future,” said the the authors write, “when the stranding zone migrates to the stabilizing high points of the seabed.” This leads to “major uncertainty for future sea level projections” and leads us all to hope that those Thwaites nails hold firm.