Scientists Discover Enormous Cavity Growing Beneath Antarctica!

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Antarctica is not in a good place. In the space of only decades, the continent has lost trillions of tonnes of ice at alarming rates we can’t keep up with, even in places we once thought were safe.

Now, a stunning new void has been revealed amidst this massive vanishing act, and it’s a big one: a gigantic cavity growing under West Antarctica that scientists say covers two-thirds the footprint of Manhattan and stands almost 300 metres (984 ft) tall.

This huge opening at the bottom of the Thwaites Glacier – a mass infamously dubbed the “most dangerous glacier in the world” – is so big it represents an overt chunk of the estimated 252 billion tonnes of ice Antarctica loses every year.

017 thwaites glacerThwaites Glacier (NASA/OIB/Jeremy Harbeck)

Researchers say the cavity would once have been large enough to hold some 14 billion tonnes of ice. Even more disturbing, the researchers say it lost most of this ice volume over the last three years alone.

“We have suspected for years that Thwaites was not tightly attached to the bedrock beneath it,” says glaciologist Eric Rignot from the University of California, Irvine, and NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California.

“Thanks to a new generation of satellites, we can finally see the detail.”

Rignot and fellow researchers discovered the cavity using ice-penetrating radar as part of NASA’s Operation IceBridge, with additional data supplied by German and French scientists.

According to the readings, the hidden void is but one ice casualty among a “complex pattern of retreat and ice melt” that’s taking place at Thwaites Glacier, sectors of which are retreating by as much as 800 metres (2,625 ft) every year.

The complex pattern the new readings reveal – which don’t fit with current ice sheet or ocean models – suggest scientists have more to learn about how water and ice interact with one another in the frigid but warming Antarctic environment.

“We are discovering different mechanisms of retreat,” first author of the new paper, JPL radar scientist Pietro Milillo explains.

031 thwaites glacier cavity antarcticaGrowing cavity is red mass in centre (NASA/JPL-Caltech)

While researchers are still learning new things about the complex ways ice melts at the Thwaite Glacier, at its most basic, the giant cavity represents a simple (if unfortunate) scientific actuality.

“[The size of] a cavity under a glacier plays an important role in melting,” Milillo says.

“As more heat and water get under the glacier, it melts faster.”

That’s important to know, since Thwaites currently accounts for about 4 percent of global sea level rise.

If it were to disappear entirely, the ice held in the glacier could lift the ocean by an estimated 65 centimetres (about 2 ft). But that’s not even the worst-case scenario.

The Thwaites Glacier actually holds in neighbouring glaciers and ice masses further inland. If its buttressing force disappeared, the consequences could be unthinkable, which is why it’s considered such a pivotal natural structure in the Antarctic landscape.

Just how long it will stay, nobody knows – which is why scientists are right now embarking on a major expedition to learn more about Thwaites.

What they’ll find remains to be seen, but it’s inarguably among the most important scientific research being conducted in the world right now.

As New York University geoscientist David Holland, who wasn’t involved in the current study, told The Washington Post last year: “For global sea-level change in the next century, this Thwaites glacier is almost the entire story.”

The findings are reported in Science Advances.

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Comments (16)

  • Avatar

    Squidly

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    “covers two-thirds the footprint of Manhattan”

    Seriously? .. that’s it? .. For those of you who are not aware, Manhattan is TINY !! .. when one compares the size of Manhattan to the continent of Antarctica, Manhattan is barely a pixel on the screen.

    Puleeez … give me a break. This is 100% unadulterated fear mongering bullshit.

    Reply

  • Avatar

    Al Shelton

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    But but, but Squidly.. This may be a “carbon” footprint. In which case we are all doomed..;^D

    Reply

    • Avatar

      Squidly

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      Oh, why didn’t you say so before? … now I am skeert ..!!! .. 🙂

      Reply

    • Avatar

      Charles Higley

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      Voids appearing under glaciers ARE NOT due to global warming. One has to have the sense to know that that is not how warming and heat works. Let’s consider all he volcanoes under the Antarctic Ice Sheet and take a deep breath. Whatever is going on down there is entirely not out fault and out of our hands.

      Reply

  • Avatar

    VICB3

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    I’m surprised that nobody seems to consider or at least mention the possibility of local sub-surface volcanism/geologic activity as a likely heat source for the melting. So much more straightforward than some convoluted hot/cold ocean current global warming/climate change thing

    I guess it’s easier (and a lot more pleasurable) simply to self-flagellate whilst bemoaning the evils of modern civilization.

    Just a thought.

    VicB3

    Reply

    • Avatar

      Lauchlan Duff

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      Abstract from de Vrievs etal 2017 “A New volcanic province: an inventory of subglacial volcanoes in West Antarctica”
      “The West Antarctic Ice Sheet overlies the West Antarctic Rift System about which, due to the comprehensive ice cover, we have only limited and sporadic knowledge of volcanic activity and its extent. Improving our understanding of subglacial volcanic activity across the province is important both for helping to constrain how volcanism and rifting may have influenced ice-sheet growth and decay over previous glacial cycles, and in light of concerns over whether enhanced geothermal heat fluxes and subglacial melting may contribute to instability of the West Antarctic Ice Sheet. Here, we use ice-sheet bed-elevation data to locate individual conical edifices protruding upwards into the ice across West Antarctica, and we propose that these edifices represent subglacial volcanoes. We used aeromagnetic, aerogravity, satellite imagery and databases of confirmed volcanoes to support this interpretation. The overall result presented here constitutes a first inventory of West Antarctica’s subglacial volcanism. We identified 138 volcanoes, 91 of which have not previously been identified, and which are widely distributed throughout the deep basins of West Antarctica, but are especially concentrated and orientated along the >3000 km central axis of the West Antarctic Rift System.”

      Reply

  • Avatar

    Midnighteye

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    “For global sea-level change in the next century, this Thwaites glacier is almost the entire story.” It looks as if the Greenland ice cap isn’t so important after all.

    Reply

  • Avatar

    Steve Dembo

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    If there was an award for the sciences like the Oscars for Entertainment, I would swear these scientists are all trying to get their Oscar. The Doom and Gloom train rattles on.

    Reply

  • Avatar

    Steve Garai

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    My favourite part of this article:

    “While researchers are still learning new things about the complex ways ice melts at the Thwaite Glacier, at its most basic, the giant cavity represents a simple (if unfortunate) scientific actuality.
    “[The size of] a cavity under a glacier plays an important role in melting,” Milillo says.
    “As more heat and water get under the glacier, it melts faster.”
    That’s important to know, since Thwaites currently accounts for about 4 percent of global sea level rise.”

    Although the article admits they still have a lot to learn about the complexity of ice melt (especially if there is a cavity underneath presumably) in the next breath they make a breathtaking prediction with no hint of uncertainty – that the piece of ice under consideration represents exactly 4% of all seal level rise!

    Even before the reader can fully process the aforementioned, the article immediately launches its next stunning revelation: if you increase heat and water flow under an iceberg it melts faster! Now that’s real science!

    Hilarious!

    Steve

    Reply

    • Avatar

      Robert Beatty

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      “Although the article admits they still have a lot to learn about the complexity of ice melt”
      It seems to me that all they need to learn is that sea ice with a cavity under it is floating and will have NO effect on sea levels when it melts.

      Reply

      • Avatar

        Herb Rose

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        Hi Robert,
        I Think the article says the glacier is not floating but on land, If this is the case when the ice comes off the land and begins to float it will displace water causing an increase in sea level.
        Have a good day,
        Herb

        Reply

        • Avatar

          Robert Beatty

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          Thanks Herb,
          I read the dark black line as being the coast line in the satellite image, which puts the glacier shelf offshore. This is the same outline tomomason shows near the Italy boot in his overlay image?

          Reply

  • Avatar

    richard

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    The melting is having such an effect that the Thames Barrier closings have decreased since 2000.

    Reply

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