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Thread: The Larsen Ice shelf breaks off.

  1. #1
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    Default The Larsen Ice shelf breaks off.

    That big slice of the Larsen Ice shelf has finally cracked off and is away and floating. Thirty meters above water and round 200 below. I understand a bigger one broke off somewhere in the 1950's, it seems it's what ice shelves do.
    "One of the biggest icebergs on record has broken away from Antarctica, scientists have said, creating an extra hazard for ships around the continent as it breaks up.The 1 trillion-tonne iceberg, measuring 5,800 square kilometres, calved away from the Larsen C ice shelf in Antarctica sometime between July 10 and 12, scientists at the University of Swansea and the British Antarctic Survey said."
    http://www.abc.net.au/news/2017-07-1...-shelf/8703238


    Larsen B in 2002
    https://www.youtube.com/watch?v=zIcLuiTt4f4

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    Default Re: The Larsen Ice shelf breaks off.

    Maybe we should get some scientists and pundits together to debate whether it's actually happening.

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    Default Re: The Larsen Ice shelf breaks off.

    Time to get out the topographic maps and find the next decades waterfront property.
    Skip

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    Default Re: The Larsen Ice shelf breaks off.

    A science guy reports that this was not related to climate change. It is just a large example of a naturally occurring event.
    The calving caused by climate change starts with large pools melting on the surface of a glacier. That melt water then seeps into cracks and crevices where it freezes and expands and forces large pieces to fall off. It's sort of like a mason splitting granite with wedges.
    “What, Me Worry?". -. A. E. Newman

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    Default Re: The Larsen Ice shelf breaks off.

    Going to have to add a foot or so to my mooring chains. Bugger.

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    Default Re: The Larsen Ice shelf breaks off.

    Well the interesting part now is how quickly the land based part of the glacier accelerates now the blocking shelf has gone.

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by twodot View Post
    To be pedantic, if the ice shelf is floating, then it won't contribute to sea level rise.
    You must know more about it than me. There I was thinking it's no longer supported by the bigger block of ice or any solid land has broken off and slid or fell, or whatever down into the water so it now has to float on its own.

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by skuthorp View Post
    Well the interesting part now is how quickly the land based part of the glacier accelerates now the blocking shelf has gone.
    Might get the mooring guy to add 2 feet while he's down there.

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    Default Re: The Larsen Ice shelf breaks off.

    Interesting. So if instead of calving small bergs like usual, it gave way at those neatly illustrated fault lines top and bottom further back, would it just maintain its displacement, or does it drop down into the sea somewhat I wonder?

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by Jim Bow View Post
    A science guy reports that this was not related to climate change. It is just a large example of a naturally occurring event.
    The calving caused by climate change starts with large pools melting on the surface of a glacier. That melt water then seeps into cracks and crevices where it freezes and expands and forces large pieces to fall off. It's sort of like a mason splitting granite with wedges.
    Greenland

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by twodot View Post
    It is so far out to sea that it is already completely afloat when breaks off.
    All good then, whew.

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    Default Re: The Larsen Ice shelf breaks off.

    But it does affect water temperature which in turn affects weather patterns, at least up here on the other pole.
    A society predicated on the assumption that everyone in it should want to get rich is not well situated to become either ethical or imaginative.

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by twodot View Post
    This figure, from the article linked above, illustrates the parent glacier, the "grounding line" (I love that term), and the ice shelf (which is floating):



    A lot of the melting occurs at the grounding line, because the ice there is under tremendous pressure, and warming water will melt it faster (as I recall).
    Thanks for the image.
    Let's review the different reasons why a ice sheet can calf off a larger then normal iceberg.
    1. The ice flow speed could increase
    a. increase water under the land base ice could cause this.
    b. increase buildup of snow and ice on top of the land based ice could cause this.
    2. The thickness/weight of the ice at the tip could increase causing it to break off.
    Increased snow fall could cause this.
    3. The water temperature could be increasing
    a. Water temp in general could be increasing
    b. An underwater volcano could cause a local increase in water temperature.
    4. Physical movement of the Ice
    a. a large storm and the wave action could cause a break to start.
    b. an earthquake could also cause the break to start.

    Let's look and see is there is anything special about the area of the Larson Ice sheet.
    1. The area of the Larson Ice sheet is near the edge of the Antarctic tectonic plate.
    2. A magnitude 6.0 earthquake struck near Livingston Island, Antarctica on October 27 2009.
    3. In 2013 an active Volcano was found under the ice.
    Not in the area of Larsen ice sheet but it shows that new volcanoes are being found.
    4. In 2011 Giant Undersea Volcanoes were found off Antarctica.
    Again not in the location of the Larsen Ice Sheet but it does show that new volcanoes are being found.


    https://en.wikipedia.org/wiki/Antarctic_Plate
    https://en.wikipedia.org/wiki/List_o...quakes_in_2009
    http://news.nationalgeographic.com/n...-rise-science/
    http://news.nationalgeographic.com/n...ence-tsunamis/

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by PeterSibley View Post
    Greenland

    Surface of Europa



    I was struck immediately by the similarity.

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    Default Re: The Larsen Ice shelf breaks off.

    The scientists think that the break was the furthest back for 10,000 years. Evidently the sea floor retains that information.
    And the temperatures there are rising faster than most places in the antarctic according to an interview I heard.

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by twodot View Post
    Where did you get your idea of volcanoes? You linked to Nat'l Geo, but what led you there?

    Because, although volcanoes might contribute to melting, nobody has suggested that they are the reason for the breakoff.

    Or, can you provide your link?
    It seem that everyone just jumps to the conclusion the break off was a direct cause of Man Made Global Warming.
    So I was just thinking of all the possible reasons why an ice sheet can break off a large iceberg.
    Volcanoes was just one possible reason.

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by genglandoh View Post
    It seem that everyone just jumps to the conclusion the break off was a direct cause of Man Made Global Warming.
    Fundamentally untrue.
    Simpler is better, except when complicated looks really cool.

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by genglandoh View Post
    It seem that everyone just jumps to the conclusion the break off was a direct cause of Man Made Global Warming.
    So I was just thinking of all the possible reasons why an ice sheet can break off a large iceberg.
    Volcanoes was just one possible reason.
    Gravity another

  19. #19
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    Default Re: The Larsen Ice shelf breaks off.

    An increase in water level could be a reason, and heat is generated at the base of the shelf where it touches the sea floor by friction. But likely this is just part of a naturally occurring cycle.

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by twodot View Post
    Bump. Where did you get your idea of underwater volcanoes as being responsible for the break?
    I already answered your question.

    I guess the Larsen Ice shelf is not the only thing cracking up.

  21. #21
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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by twodot View Post
    No, you did not answer my question. I asked you how you came up with the idea that undersea volcanoes might be responsible for the Larsen ice shelf break. Your links are years old, and the break is recent. I was wondering what website you read, since I think that you read it very recently. To suggest , rather, that I am cracking up is insincere.
    I did answer your question here it is a 2nd time

    Quote Originally Posted by genglandoh View Post
    It seem that everyone just jumps to the conclusion the break off was a direct cause of Man Made Global Warming.
    So I was just thinking of all the possible reasons why an ice sheet can break off a large iceberg.
    Volcanoes was just one possible reason.

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by skuthorp View Post
    An increase in water level could be a reason, and heat is generated at the base of the shelf where it touches the sea floor by friction. But likely this is just part of a naturally occurring cycle.
    Yes if the water level increase the tip of the sheet lift up and maybe cracking the ice off.
    I added it to my list.

    Let's review the different reasons why a ice sheet can calf off a larger then normal iceberg.
    1. The ice flow speed could increase
    a. increase water under the land base ice could cause this.
    b. increase buildup of snow and ice on top of the land based ice could cause this.
    2. The thickness/weight of the ice at the tip could increase causing it to break off.
    Increased snow fall could cause this.
    3. The water temperature could be increasing
    a. Water temp in general could be increasing
    b. An underwater volcano could cause a local increase in water temperature.
    4. Physical movement of the Ice
    a. a large storm and the wave action could cause a break to start.
    b. an earthquake could also cause the break to start.
    c. Water levels could have increased causing the ice to lift up cracking it off.

    Let's look and see is there is anything special about the area of the Larson Ice sheet.
    1. The area of the Larson Ice sheet is near the edge of the Antarctic tectonic plate.
    2. A magnitude 6.0 earthquake struck near Livingston Island, Antarctica on October 27 2009.
    3. In 2013 an active Volcano was found under the ice.
    Not in the area of Larsen ice sheet but it shows that new volcanoes are being found.
    4. In 2011 Giant Undersea Volcanoes were found off Antarctica.
    Again not in the location of the Larsen Ice Sheet but it does show that new volcanoes are being found.


    https://en.wikipedia.org/wiki/Antarctic_Plate
    https://en.wikipedia.org/wiki/List_o...quakes_in_2009
    http://news.nationalgeographic.com/n...-rise-science/
    http://news.nationalgeographic.com/n...ence-tsunamis/

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by twodot View Post
    And I was wondering how you came up with the idea of volcanoes. You seem reluctant to state that you came up with it yourself, rather than reading it recently.

    For example, you just posted a thread hypothesizing voter fraud in Colorado, and link to th Denver Post. But, it is unlikely that you read the Denver Post, and therefore got the idea from another website. I think that, similarly, you laundered your undersea volcano links, citing Natl Geo rather than your true source.

    As an aside, your Denver Post link cites several plausible explanations other than voter fraud, but you ignored these, suggesting your idea came from another source.
    I am sorry if you do not understand my post.
    I clearly said that I was thinking of all the possible reasons why the ice shelf would break off.

    Is it that hard to understand?

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by genglandoh View Post
    I am sorry if you do not understand my post.
    I clearly said that I was thinking of all the possible reasons why the ice shelf would break off.

    Is it that hard to understand?
    You forgot perturbations in the earths rotation and voter fraud

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    Default Re: The Larsen Ice shelf breaks off.

    A slow day at the office Twodot?
    It really is quite difficult to build an ugly wooden boat.

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    Default Re: The Larsen Ice shelf breaks off.

    It is the gravity... Voting for the pro-gravity candidate is a fools errand.

    Locally we have a support group for those with gravity related anger management issues.

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    Default Re: The Larsen Ice shelf breaks off.

    Like shooting ducks in a barrel.

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by twodot View Post
    Every once in a while it is fun to try to source the laundering, knowing that there will be an evasive dance.
    If you have a reference you want to talk about please post it.

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    Default Re: The Larsen Ice shelf breaks off.

    Interesting an earthquake in Chile can cause ice-quakes in Antartica.

    Title: Chilean earthquake triggered icequakes in Antarctica
    Link: http://www.abc.net.au/science/articl...11/4063704.htm

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by twodot View Post
    Every once in a while it is fun to try to source the laundering, knowing that there will be an evasive dance.
    NewsMax, social media, Heritage Foundation via FoxNews, etc

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    Default Re: The Larsen Ice shelf breaks off.


  32. #32
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    Default Re: The Larsen Ice shelf breaks off.

    There are reports in ships logs in the late 1800's of icebergs "10 miles long and 200 feet high" so this event is likely cyclical.
    As far as seismic activity goes the weight of the ice has pushed the land under it down, and as the weight of the ice diminishes it will rebound causing quakes and possibly hot spots as in Greenland. I don't think anyone has suggested that the latest event was climate related.
    https://www.livescience.com/46194-vo...-glaciers.html

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    Default Re: The Larsen Ice shelf breaks off.

    Quote Originally Posted by Canoeyawl View Post
    Love that

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    Default Re: The Larsen Ice shelf breaks off.

    Well if you look at the underwater geology and where the 'ice quakes' occurred it's not so surprising. Unre that ice against the underlying rock is a layer of melt water created by the pressure. A shake will trigger a slip.

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    Default Re: The Larsen Ice shelf breaks off.

    An excellent image of the new iceberg.

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