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Cracks Signal Massive Iceberg Forming In Antarctica 147

Several readers have submitted news (as covered by an AFP article carried by the Sydney Morning Herald) that a massive iceberg is forming in the Antarctic. The rift in the PIne Island Glacier "is widening at a rate of two metres a day, said NASA project scientist Michael Studinger. When the ice breaks apart, it will produce an iceberg more than 880 square kilometres, said Mr Studinger, who is part of the US space agency's IceBridge project. But the process is not a result of global warming, he said." Also at the BBC.
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Cracks Signal Massive Iceberg Forming In Antarctica

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  • See? (Score:4, Funny)

    by mustPushCart ( 1871520 ) on Sunday November 06, 2011 @07:23AM (#37964354)

    Global warming isn't shrinking the icebergs, its creating new ones!

    • Re:See? (Score:5, Informative)

      by Layzej ( 1976930 ) on Sunday November 06, 2011 @08:01AM (#37964466)

      A paper published in Nature back in December describes the cause: http://www.nature.com/ngeo/journal/v4/n8/full/ngeo1188.html [nature.com]

      Here we combine our earlier data with measurements taken in 2009 to show that the temperature and volume of deep water in Pine Island Bay have increased. Ocean transport and tracer calculations near the ice shelf reveal a rise in meltwater production by about 50% since 1994. The faster melting seems to result mainly from stronger sub-ice-shelf circulation, as thinning ice has increased the gap above an underlying submarine bank on which the glacier was formerly grounded. We conclude that the basal melting has exceeded the increase in ice inflow, leading to the formation and enlargement of an inner cavity under the ice shelf within which sea water nearly 4C above freezing can now more readily access the grounding zone.

  • Will it move into warmer waters (and melt?)
    • That, or hit New York [fantasticfiction.co.uk].

    • by Snard ( 61584 )

      (Prefix: I RTFA and it doesn't answer this question)

      Even if the iceberg doesn't melt, if it's currently on dry land and it falls into the ocean, I assume it will raise ocean levels by some small amount. Does any know how much?

      • Re: (Score:2, Informative)

        by Anonymous Coward

        From wikipedia: [wikipedia.org]
        About 98% of Antarctica is covered by ice that averages at least 1.6 kilometres (1.0 mi) in thickness.

        From summary:
        it will produce an iceberg more than 880 square kilometres.

        From wikipedia: [wikipedia.org]
        Surface area
        510,072,000 km2[12][13][note 5]
        148,940,000 km2 land (29.2 %)
        361,132,000 km2 water (70.8 %)

        From google [google.se]:
        ((880 (km^2)) * (1,6 km)) / (361 132 000 (km^2)) = 3,89885139 millimeters

        Answer: About 4mm.

        • Re:Where will it go? (Score:4, Informative)

          by Arlet ( 29997 ) on Sunday November 06, 2011 @08:21AM (#37964536)

          The end of the glacier is much thinner than the average antarctic ice sheet, and it's already floating in the water, still attached to the glacier. If it breaks off, it's not going to raise water levels any more.

          • Actually, the small amount of mass above the water line will go below the waterline when it melts, thus raising the waterline. However, water contracts when melting, which will more than make up for the change in level. The displacement of the ice is thus exactly the displacement of the melted water.

            You can test this easily: leave some ice in a glass and note the waterline before and after melting.

            • by Arlet ( 29997 )

              There are some small differences though. The ice is mostly fresh water, and the surrounding seas contain salt. The melting will cause a small, net rise in sea level. This is a very small effect, though.

              Also, the local gravity field from the ice pulls the surrounding sea water closer to the pole. If the pole loses mass, the water will spread out more.

      • by Anonymous Coward

        If it were currently on dry land, we'd call it a glacier, not an iceberg.

        It's already in the ocean, so cracking off and drifting into the open ocean will not raise sea levels.

        What happens when it melts? Here's an experiment for you. Put an ice cube in a small glass of water, e.g. a shot glass. Mark the water level. Wait for the ice to melt. What happened to the water level?

        See, even you can do science in your kitchen.

        • by Canazza ( 1428553 ) on Sunday November 06, 2011 @09:57AM (#37964830)

          you'll also end up with a warm Gin and Tonic, but who said you didn't have to suffer for science?

          • If there isn't any quinine in it, it's not a gin and tonic. You want to get malaria or something?

            I've always wondered whether the gin was supposed to help the quinine go down, or the other way around.....

      • One gigatonne of ice melting into the ocean adds about 3 microns to the surface. In this case, 880 square kilometers of ice that varies between 60 and 500 meters thick is going to take a very very long time to melt and will result an addition of water that is almost zero once evaporation is factored in... the article points out that this iceberg might end up being about the size, in terms of surface area, as Berlin. Antarctica is almost entirely covered in Ice, 44% of which is floating in the ocean, and
        • I want to put a bunch of motors on this baby and drive it around. About 3 nuclear reactors should provide enough power, I just need to figure out how to get the correct amount of propellers.

  • by mosb1000 ( 710161 ) <mosb1000@mac.com> on Sunday November 06, 2011 @07:28AM (#37964364)

    But the process is not a result of global warming, he said.

    Does it bother anyone else that they had to say this? It's like doing a report on spring runoff and pointing out that it's not a result global warming. Are people really that ignorant of how natural processes work?

    • by Anonymous Coward

      Do you really need an answer to this?

    • Re: (Score:1, Flamebait)

      by obarthelemy ( 160321 )

      I'm no expert. Intuitively, a block of ice breaking away from a bigger block of ice kinda makes me think there's melting, thus warming, involved.

      • by Anonymous Coward on Sunday November 06, 2011 @07:53AM (#37964446)

        "...Intuitively, a block of ice breaking away from a bigger block of ice kinda makes me think there's melting, thus warming, involved..."

        Why do you think that? This is the end of a GLACIER. Usually, glaciers move (slowly) downhill, until they reach warmer regions, where they melt. In this case the glacier moved downhill until it met the sea, upon which it floated out. After a fair bit has floated out, it will break off, due to flexing in the waves and tides. That is what has just happened, with a rather big bit...

        Actually, if it is cold and snowy up in the mountains, the glaciers will move faster. And more bits will fall off the end of the glacier, more rapidly. This is often shot by journalists at the foot of the glacier, and used as 'confirmation of Global Warming'.....

        • Actually, if it is cold and snowy up in the mountains, the glaciers will move faster. And more bits will fall off the end of the glacier, more rapidly.

          As long as the temperature isn't too high, a higher temperature should result in more snow since there will be more water vapour in the air.
          This, of course, is under the assumption that the temperature is still well below 0C.

      • by Anonymous Coward

        The articles state that this glacier breaks off every 10 years or so. The last time was 2001.

      • Yes, we call that a summer, it happens on a yearly basis.
      • I'm no expert. Intuitively, a block of ice breaking away from a bigger block of ice kinda makes me think there's melting, thus warming, involved.

        TFA says that they're making the announcement to try and avoid all the sensationalist news stories that will appear when the mainstream media gets hold of it.

        Wonder if it will work...

      • by jrumney ( 197329 )
        Global warming is so last decade. I blame fracking, myself.
    • by DamonHD ( 794830 ) <d@hd.org> on Sunday November 06, 2011 @07:36AM (#37964396) Homepage

      It seems reasonable and responsible to avoid this being dragged into the AGW/CC debate one way or another if the scientists concerned are pretty sure that CC plays no significant part in this event, because lots of glacier/calving activity *has* been tied to CC, pro or anti.

      So, it wouldn't be ignorance that would lead people to wonder. And thus forestalling inappropriate linkage is good.

      Rgds

      Damon

    • by Arlet ( 29997 )

      Are people really that ignorant of how natural processes work?

      Yes. I hope this doesn't come as a big surprise.

    • Apparently many people are not aware that snow melts every spring. That was my bad.

      • by Arlet ( 29997 )

        Spring snow melting has nothing to do with this though. It's a frozen sheet of ice, slowly sliding into the ocean, and when it's gets too big and thin, a piece breaks off. The last time this happened was in 2001.

    • I suppose we could say it is related to hemispheric warming. I prefer the term Summer, however.
    • by osu-neko ( 2604 )

      Does it bother anyone else that they had to say this? It's like doing a report on spring runoff and pointing out that it's not a result global warming. Are people really that ignorant of how natural processes work?

      It's not really like that, no. Spring runoff happens every year, and it happens in areas of the world inhabited by the readership of said news service. Country-sized iceburgs only break off this shelf about once every ten years, and it happens half a world away from the readership of said news service. Are people really that ignorant of the differences in frequency and location of natural processes, and the likely effect that has on the familiarity of most people with them?

    • If the ice shelf breaks away, it gets out of the way of the glacier that is still on land, which then accelerates. This does add more water to the oceans, and so raises sea level. In fact, the Pine Island Glacier has accelerated since people have been monitoring it, and the ice shelf, when measured after each iceberg breaks off, has been getting smaller.

  • by Anonymous Coward
    From the BBC:

    In recent years, satellite and airborne measurements have recorded a marked thinning of the PIG, which may be related to climate changes.

    From The Syndey Morning Herald:

    When the ice breaks apart, it will produce an iceberg more than 880 square kilometres, said Mr Studinger, who is part of the US space agency's IceBridge project. But the process is not a result of global warming, he said.

    The BBC also conveniently did not include that last sentence from the source. I don't know what this tells you, but to me it appears as if the BBC intentionally wanted to scare its readers with global warming. Seems like the BBC is also illiterate and can't write properly (they write Nasa instead of NASA, yet PIG instead of Pig).

  • Bipolar antarctica sad about recent news.

  • by lkcl ( 517947 ) <lkcl@lkcl.net> on Sunday November 06, 2011 @08:58AM (#37964628) Homepage

    yeah, it's the penguins and the polar bears, they've been lighting fires.

    • by izomiac ( 815208 )
      Plus the carbon footprint for getting the bears to Antarctica! Though I'd imagine that'd take polar bears off the threatened species list, and put penguins on it...
  • Video on the crack (Score:5, Informative)

    by Stirling Newberry ( 848268 ) on Sunday November 06, 2011 @09:29AM (#37964712) Homepage Journal
    As one of the readers who mentioned this in a submission: http://video.stv.tv/bc/ITN_041111_worldICEBERG04/?redirect=no [video.stv.tv] is a good short video story version on this, including some graphics on ice flows and pictures of the crack. Quite well done. Not this isn't a GW/CC event, but it is a chance to see the formation of a crack in progress, which we do not always catch. All icebergs start with this cracking process, and icebergs form in warm and cold periods of history. Understanding the ice dynamics of how flows of build up turn into stress is the ice equivalent of studying plate tectonics: the science of large solid plates bending, cracking, and then failing.
  • What would happen if something that size hit a country or continent at say, 1 meter per second? I'm not sure of the magnitude of that kind of catastrophe at all.

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      The same thing that happens when similar sized bergs hit land, as they do all the time in the polar regions.

      They ground in water which is about 100-200ft depth, and leave big gouges in the bottom.

      • by Twinbee ( 767046 )

        Which I'm sure would be awesome to see which is probably why there's no video footage of that kind of thing anywhere (let alone in high resolution).

    • by mevets ( 322601 )

      I think I smell an action flick here. Maybe we can send Bruce Willis and Clint Eastwood on a suicide mission (please!) to nuke the iceberg before it makes landfall.

      Of course, they would have to battle laser equipped sharks and a stultifying bureaucracy....

      • by tqk ( 413719 )

        I think I smell an action flick here. Maybe we can send Bruce Willis and Clint Eastwood on a suicide mission (please!) to nuke the iceberg before it makes landfall.

        Of course, they would have to battle laser equipped sharks and a stultifying bureaucracy....

        ... and "terrist" Guaa'ulds who'd secretly loaded the berg with Naquadria and were driving it up the Potomac toward the Pentagon! Wanna try to get a Kickstarter project going?

        [Obligatory Grammar Nazi contribution: is that an elipsis followed by a period?]

    • by Stirling Newberry ( 848268 ) on Sunday November 06, 2011 @11:25AM (#37965282) Homepage Journal
      You should look up the epic of iceberg B-15, for a time "the largest floating thing on the planet." It was one of the Icebergs that calved from the break up of the Ross Ice Shelf, and 11,000 km^2 – that's the size of Jamaica, Bylot, or Bloshevik Island, and larger than the "big island" of Hawai'i. It broke apart several times, bashed into the Drygalski Ice Tongue, gouging out an 8km^2 piece, and floated on, breaking into smaller pieces, though some of its remains are still wandering around the Antarctic Ocean.
      http://www.esa.int/esaCP/ESAAQTTHN6D_index_0.html [esa.int] [ESA]
      The ESA has a great deal of imagery on it.
  • Shouldn't it be measured in cubic kilometers?

    • Actually I believe the proper units are libraries of Congress...
      • by sjwt ( 161428 )

        as we are using metric here and also talking Antarctica, that would come under Australian metric measurements, that would be measured in VSH - Volume of Sydney Harbour, and we all knows that's 562,000 megalitres (562 million cubic metres), as I don't know the average thickness of this piece of ice(the article seem to state it runs 50m thick, but is that an average or just the max?), I shall leave it to someone else to work out.

    • by HiThere ( 15173 )

      That would make it seem smaller, as antarctic icebergs tend to be low and flat. I'd guess that it averages less than 500 meters thick, and it probably doesn't have the photogenic high peak that make arctic icebergs so spectacular. Saying an iceberg is 9/10 underwater may be true, but if there isn't anything high above water, that doesn't push them down very far.

  • There are many regions around the world, particularly in India and Africa that are desperate for fresh water. Why not send a tanker up there with a legion of laborers to harvest these icebergs? Instead of just letting it melt into the ocean.

    People may not know this, but before modern refrigeration, workers used to manually harvest big blocks of ice out of lakes with saws. Then your local Ice-guy would walk up to the side of your house, open a little door and stick a smaller block of ice through your wall

    • There are many regions around the world, particularly in India and Africa that are desperate for fresh water. Why not send a tanker up there with a legion of laborers to harvest these icebergs? Instead of just letting it melt into the ocean.

      People may not know this, but before modern refrigeration, workers used to manually harvest big blocks of ice out of lakes with saws. Then your local Ice-guy would walk up to the side of your house, open a little door and stick a smaller block of ice through your wall, and into your icebox. This was how you kept food relatively cool.

      What a brilliant idea! I highly doubt such a concept has ever been conceptualized before!

  • Cracks have been seen as far north as central Oklahoma! lol

  • nature is fighting back, creating an army of icebergs to sink all our ships!

I tell them to turn to the study of mathematics, for it is only there that they might escape the lusts of the flesh. -- Thomas Mann, "The Magic Mountain"

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