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Earth Science

A Hole Opens Up Under Antarctic Glacier -- Big Enough To Fit Two-Thirds of Manhattan (nbcnews.com) 281

Posted by msmash from the stranger-things dept.
Scientists have discovered an enormous void under an Antarctic glacier, sparking concern that the ice sheet is melting faster than anyone had realized -- and spotlighting the dire threat posed by rising seas to coastal cities around the world, including New York City and Miami. From a report: The cavity under Thwaites Glacier in West Antarctica is about six miles long and 1,000 feet deep -- representing the loss of 14 billion tons of ice. It was discovered after an analysis of data collected by Italian and German satellites, as well as NASA's Operation IceBridge, a program in which aircraft equipped with ice-penetrating radar fly over polar regions to study the terrain. The discovery is described in a paper published Jan. 30 in the journal Science Advances. The researchers expected to see significant loss of ice, but the scale of the void came as a shock.
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A Hole Opens Up Under Antarctic Glacier -- Big Enough To Fit Two-Thirds of Manhattan More

A Hole Opens Up Under Antarctic Glacier -- Big Enough To Fit Two-Thirds of Manhattan

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  • Rats. They found me. (Score:5, Funny)

    by Opportunist ( 166417 ) on Thursday February 07, 2019 @12:45PM (#58084336)

    So much for my Fortress of Solitude.

  • Iron Sky 2 (Score:5, Funny)

    by Oswald McWeany ( 2428506 ) on Thursday February 07, 2019 @12:46PM (#58084344)

    Wasn't this the proposed theme to Iron Sky 2. Hint: It's Lizard people living down there below Antarctica.

  • Quit flying planes over it then!

  • Stop Building there!

    PLENTY of available land in Colorado!

    • Re: (Score:3)

      by hey! ( 33014 )

      PLENTY of available land in Colorado!

      If you don't mind the alternating droughts, floods, wildfires and plagues of insects.

      • PLENTY of available land in Colorado!

        If you don't mind the alternating droughts, floods, wildfires and plagues of insects.

        That last one is just about gone [scientificamerican.com]

        • Re: (Score:2)

          by hey! ( 33014 )

          A reduction in wild insect biodiversity doesn't mean that, say, crop pests won't thrive.

          This is evolution in action; as human impacts affect the biosphere more, you get a swing toward species that are well adapted to human disruptions.

    • All Full, No More Room (Score:2, Insightful)

      by Anonymous Coward

      Nope, Colorado is full. you idiots from SoCal came and parked in the fucking left lane of the interstate. That and you went to escape the cost of living down there, and brought your retarded politics to run up the cost of living here.

      • Re: (Score:2)

        by Hylandr ( 813770 )

        So much this. Why won't California natives learn it's their bullshit 'there should be a law against that or tax the shit out of it' ideals that bring the high cost of living with them?

    • Re: (Score:3)

      by macraig ( 621737 )

      Plenty of land until developers start taking you up on your foolish offer....

  • So... (Score:3)

    by reanjr ( 588767 ) on Thursday February 07, 2019 @12:51PM (#58084376) Homepage

    So, there's less ice than we thought and the rise in sea levels has not been as severe as we thought for the amount of ice that has melted. How is this not a positive thing?

    • Re:So... (Score:5, Informative)

      by Anonymous Coward on Thursday February 07, 2019 @01:02PM (#58084444)

      No, puny human, the entire ice shelf is thousands of time larger than the hole that was discovered.

      However, the undermining of the ice shelf has advanced more than expected and portends the entire ice shelf, as well as the glaciers behind it melting out to sea.

      • And if this collapses, a huge chunk of glacier will be floating out to warmer waters and melting faster still.

    • Re:So... (Score:5, Informative)

      by hey! ( 33014 ) on Thursday February 07, 2019 @01:53PM (#58084758) Homepage Journal

      I understand it's hard to grasp the scale of what we're talking about here. Just to give you a sense, the glacier in question has an area of 166,500 km^2 or roughly the same size as the country of Tunisia, and is about 300 meters thick. The area covered by Manhattan is only about 3/100 of 1% of that.

      The volume of missing ice represents probably less than 1/500th of the ice in the glacier. It's not the volume lost already that's the concern, it's what the void says about the vastly larger volume of ice in that glacier. Internal melting means that there is some kind of water flow occurring, which could destabilize the entire glacier. That's over 45 gigatons of ice, enough to raise global sea level by over 1/10 of a cm.

      Of course that's not very much. If this is the *only* land-based ice sheet or glacier that were unstable, it's not a sea level rise issue; it's equivalent to about one year's contribution of ocean thermal expansion to sea level rise.

      This is kind of like finding a crack in an individual Airbus A380 wing; it's not very big compared to the wing's 420 m^2 area, and this is just one wing on one out of hundreds of A380 in service. That doesn't make it a small deal.

      • Re: (Score:2)

        by Shotgun ( 30919 )

        This is kind of like finding a crack in an individual Airbus A380 wing; it's not very big compared to the wing's 420 m^2 area, and this is just one wing on one out of hundreds of A380 in service. That doesn't make it a small deal.

        It's not a small deal unless they can determine WHY there is that water flow occuring. If the A380 in question had just ran into the side of the terminal, the crack in its wing spar would not matter to the remainder of the fleet, and *might* not even be a big to this one (though, most likely it would). More interesting would be a crack in the nose gear after a particularly hard landing. This would be more likely to have ramifications for the whole fleet, since a hard landing doesn't leave the sort of evi

      • ...by over 1/10 of a cm

        Fuck's sake. Not 1/1000 of a meter??

        • Fuck's sake. Not a millimeter?

          It's not a difficult unit to use. Ants. Chocolate sprinkles. Mouse cables.

      • 1/500th sounds like a huge amount to me.

        Seems obvious if you've ever watched ice melt; once voids appear, melting accelerates rapidly.

        Like poking holes in a potato before baking; 1/500th is plenty to create air flow in a way that significantly alters the results.

        When I saw somebody making scale arguments, I figured it was going to be something small like 1/50,000th, not something catastrophically huge like 1/500th!

        • Re: (Score:2)

          by hey! ( 33014 )

          In I think it's best not to rely on our intuitions formed through our experience with small scale phenomena to anything this enormous. Best to leave that to the geophysicists.

          I'm just responding to the poster's apparent belief that the fact that the volume of missing ice proves that sea level rise due to ice sheet collapse is implausible.

      • I get that this is an important find but I have trouble believing the hype that this means that we are about to have a 2m rise in sea level - at the very least there seem to be some additional assumptions being made before that conclusion is reached. Indeed, if climate models can be so significantly affected by one unexpected find under one glacier then doesn't this suggest that the models have significant uncertainties? This is the real problem I have with the climate change discussion. One side of the med

        • Best to skip the media and go straight to the published paper.

        • Re: (Score:2)

          by hey! ( 33014 )

          This by itself does not mean we'll have a 2m sea level rise. Predicting sea level rise depends on predicting our future behavior. There's a big difference between RCP 2.6 (we do everything possible to reduce greenhouse emissions) and RCP 8.5 (we do nothing).

          It is my understanding that the middle-of-the road projections assume that the Antarctic and Greenland ice sheets will remain mostly stable, and that most of the sea level projection is due to thermal expansion. This individual finding does not *neces

    • Re:So... (Score:4, Informative)

      by jeti ( 105266 ) on Thursday February 07, 2019 @02:08PM (#58084866)
      Because the ice is a heat sink. Melting ice needs a massive amount of energy. Once its gone, temperatures will rise sharply.
    • This is 14 trillion liters of water. The oceans contain approximately 1,340,146 trillion liters of water. That's 1/10,000th of the volume. Not something you'd notice. The issue is that once the glacier loses enough strucural support/mass, they whole Flordia sized chunk will slide into the ocean. Which will add significantly more volume (Florida vs. Manhattan). And all at once.

  • They Can't Fool Me (Score:2, Funny)

    by Anonymous Coward

    It's a UFO hanger, guaranteed.

  • Comment removed based on user account deletion

    • Colonization? Yeah, we're colonized over here. All the land belongs to someone already. However, you have to wonder whether we'll end up with a mid-west coast and a mid-east coast if the mississippi rises along with sea levels. More global water probably means more rain, which means more water in the rivers too.

    • Re:I'll believe they truly are see a crisis (Score:4, Interesting)

      by kilfarsnar ( 561956 ) on Thursday February 07, 2019 @01:46PM (#58084724)

      When the scientific establishment calls for relocation policies that encourage colonization of "flyover country" in the US by the coastal population.

      I'm perfectly willing to accept the possibility that "global warming" is happening, but until the discussion is "it's happening, but why" and all "whys" are entertained including "we have no control, move in with the Hillbillies if you don't want to drown" I'm not going to give much credence to the fearmongering because skin in the game determines the degree of commitment one has.

      Really? Do you not steer your car until the last possible second before impact?

      Wouldn't it be nice to do something about the issue before we have to undergo mass migrations? If you are so willing to accept the possibility that AGW is real, and since you do have skin in the game by virtue of living on this planet, why not look into it rather than dismissing warnings a "fear mongering"? Why wouldn't you consider calls for mass relocation "fear mongering"?

    • Re: (Score:3)

      by q_e_t ( 5104099 )

      When the scientific establishment calls for relocation policies that encourage colonization of "flyover country" in the US by the coastal population.

      And then people will complain about the scientific establishment interfering in policy, which happens whenever a scientist opines on a policy area.

  • Unfathonable number (Score:5, Funny)

    by PingSpike ( 947548 ) on Thursday February 07, 2019 @12:58PM (#58084426)

    How many football fields is two thirds of a Manhattan?

  • I have a question.... (Score:5, Interesting)

    by bobbied ( 2522392 ) on Thursday February 07, 2019 @01:11PM (#58084494)

    I'm asking a serious question here, help me understand how this is possible...

    The melting is at the BOTTOM of the glacier, where the effects of climate change are at the absolute lowest, being isolated from the air above by many feet of ice, snow and other stuff. Plus, the ice that's now melted was frozen and buried centuries ago. Plus, this is now a void, so one presumes that the conductive water flowing between the rocks below and the ice above is gone.

    How is this due to global warming?

    Seems to me that this void would be from the earth below is warmer at this spot than in others... But that's geothermal changes, not climate change. Is that wrong? If so, how do we know what caused this?

    • Re:I have a question.... (Score:4)

      by Opportunist ( 166417 ) on Thursday February 07, 2019 @01:19PM (#58084554)

      Possibly 'cause the water underneath is warmer than it should be. Water is a way better thermal conductor than air.

      • Re:I have a question.... (Score:5, Insightful)

        by sbrown123 ( 229895 ) on Thursday February 07, 2019 @01:37PM (#58084672) Homepage

        Why didn't it melt across the expanse instead of just the center? This seems more like geothermal heat, as it is more directed. Climate change heating would have produced channels instead as it would follow currents which would expand across the entire glacier, not just the center.

        • Re: (Score:3)

          by q_e_t ( 5104099 )
          For the same reason that lakes form. When the channels get to a point where they don't flow due to the topology under the glacier then lakes form and can then eat into a glacier.

    • Re:I have a question.... (Score:4, Informative)

      by Anonymous Coward on Thursday February 07, 2019 @01:30PM (#58084620)

      No, the melting is caused by an increase in hydrothermal heating. The West Antarctic Rift System, 138 volcanoes known to date, is located right below it.

      https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6014989/
      (Pine Island glacier is right beside Thwaites, see map in article)

      This is known since 2014:

      https://oceanleadership.org/major-west-antarctic-glacier-melting-geothermal-sources/

      • Re:I have a question.... (Score:4, Informative)

        by q_e_t ( 5104099 ) on Thursday February 07, 2019 @02:19PM (#58084932)
        Indeed, it is known about, and contributes about 1% additional warming. It makes very little difference overall.

        • Re: (Score:2, Interesting)

          by Anonymous Coward

          Difference to what? From the paper:

          "The adjacent Thwaites glacier, which drains to the Amundsen Sea, shows strong radar returns that indicate subglacial meltwater, suggesting volcanism and high localized heat flux"

          The observed 3He excesses also indicate a geothermal source, likely in the range of icelands Grimsvötn volcano and clearly larger than your suggested 1%.

    • fresh water floats on top of salt water. Salt water has a lower freezing point. Warmer water can flow underneath. This part of the glacier is over water, not land.

      • Re: (Score:3)

        by PPH ( 736903 )

        This part of the glacier is over water

        Then it's an ice shelf, not a glacier. Terminology is important in science. Not so much in propaganda.

        • It's still part of the glacier. It's an NBC news headline - what do you expect? The body of the article does use the term ice shelf specifically, but a glacier is still a glacier until it is an iceberg. A thing can have two names, even if one is less specific than the other.

    • Re:I have a question.... (Score:5, Insightful)

      by asylumx ( 881307 ) on Thursday February 07, 2019 @01:34PM (#58084660)
      To be clear, neither the summary nor the article made any claims about global warming or global climate change (whichever you like to call it). Simply observation that a large portion of ice internal to this glacier is gone (assumed to have melted) and this raises a risk that the glacier will collapse into the ocean which, based on calculations, could raise sea levels very quickly by up to 2 ft. If that is the case, *why* it is gone is probably not the most important question, rather how do we protect in the event that the glacier collapses is where we should focus our attention.

      • Re: (Score:2)

        by gtall ( 79522 )

        "where we should focus our attention" I would start by resolving never to buy property in Florida.

        • You've got it. I've worked in the subject field and I've been to Thwaites Glacier. I don't even get into these discussions any more. If asked my opinion, I just say, "I wouldn't buy any land in Florida that I'd intend to pass down to my grandkids."

    • Re: (Score:3)

      by Holi ( 250190 )
      These tend to be caused by flowing melt water. underneath the glacier, Eventually they create dark spots on the glacier allowing them to collect and trap more heat which in turn worsens the problem.

    • Sorry, you are beyond help since you showed up on /. ...

  • Can't deny it any longer.

  • Then that is less water to fill the oceans that cause sea rise. win win!
  • Finally a place we can stick Manhattan! I kid, but no really let's do it!

    Now we just need a hole big enough for New Jersey (obvious jokes aside).

  • I wish (Score:4, Funny)

    by argStyopa ( 232550 ) on Thursday February 07, 2019 @01:45PM (#58084708) Journal

    ...if only it WOULD take 2/3 of Manhattan.
    Can we order up one about Washington DC sized?

    If this is the outcome of warming, I'm not going to really be upset?

  • This news is very serious and very bad, but I spit my coffee when I saw the first four words, which I of course misread as:

    A-Hole Opens Up

  • The hole is big enough to contain two thirds of Manhattan?! EVERYONE has to admit this is pretty fucking bad.
    The hole needs to be at least 50% larger!

  • This is what happens if you don't brush your glacier.

  • Big enough to fit two-thirds of Manhattan (Score:3)

    by Darinbob ( 1142669 ) on Thursday February 07, 2019 @05:47PM (#58085968)

    If it is a hole big enough to fit two-thirds of Manhattan, it raises the obvious question. Where should we put the other third?

  • Yes please hurry up Manhattan is in the middle of some very expensive real estate.

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