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in reply to The worst case scenario

While the media are busy hyping the melting of the Antarctic glaciers, they're conveniently ignoring the ice elsewhere in the world, which in many cases is growing rather than shrinking. I rather doubt either an ice age or global warming is going to kill us any time soon. The biggest chance for disaster is that some nut will get his hands on a few nukes and start blowing things up, which belongs more under the category of Apocalypse than anywhere else.

Or we could be impacted by a rock the size of a small moon. One can never predict these things, otherwise they wouldn't be disasters, would they?

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Re^2: (OT? political? whatever...) The worst case scenario
by ww (Archbishop) on May 15, 2006 at 13:01 UTC
    In fact, some of the ice in Antarctica is thickening, despite the accelerating outflow elsewhere. It's a phenomonon that's not satisfactorily explained today. But I'm not aware (and it's part of my business to be so) of *significant* increases anywhere else; not in the north, nor in extreme Alpine regimes.

    And while there's considerable evidence for disparate climatic change, S. vs N, it's very clear that the 'cap in Greenland -- home to a huge proportion of the northern hemisphere's frozen water -- is undergoing as much or more melting each year (over the past 8-15 for certain) than anytime in the historic record in our cores. Further, it's starting to look as though open water is more widespread and, for any given location, earlier, throughout the Arctic and, while data is *VERY* spotty, that ice-thickness is decreasing precipitously.

    All that said, TedPride's apocalyptic concerns with rocks and nukes may be better justified than any Hollywood scenarios giving us glaciers rushing south at highway speeds...

Re^2: The worst case scenario
by grinder (Bishop) on May 15, 2006 at 14:24 UTC
    conveniently ignoring the ice elsewhere in the world, which in many cases is growing rather than shrinking

    That's the strangest argument to make. Should we therefore conclude that we don't have to do anything? What we are facing is just a question of ice being distributed around the globe in a different manner, but apart from that everything is hunky-dory? I won't go skiing in the Alps any more, but the North York Moors are starting to look promising?

    And these increases more than offset the observed decrease in the Arctic, Antartic and Greenland icepacks? And those of the Alps, the Himalayas and even Mount Kilimanjaro, all of which are known to have permanent ice covers in decline?

    I doubt any increase is offsetting all that.

    • another intruder with the mooring in the heart of the Perl

Re^2: The worst case scenario
by jdporter (Paladin) on May 19, 2006 at 12:46 UTC
    I rather doubt...

    Whew! I feel much better now. Nothing to worry about.

    We're building the house of the future together.
Re^2: The worst case scenario
by pileofrogs (Priest) on May 17, 2006 at 17:39 UTC

    When it comes to melting ice and changes in sea-level, floating ice doesn't matter at all. When it melts it will take up exactly the same space as the water it displaced by floating.

    The thing we have to worry about is ice that lives on land, like the Greenland ice sheet.

    Oh, and about your moon-sized-rock: we already track everything bigger than a few kilometers. So, sure it might kill us, but we'll have a hundred years or so to think about it.

        "...we already track everything bigger than a few kilometers.

      True! Kachin... ^H^H^H
      BRAAAATTTTT
      .oO ...oops, not quick enough to correct /me.

      <error horn vibrations ebb>...

      Well, actually, only for those cases of "everything" where "everything" includes only the set whose membership is coterminus with the set "those that we happen to know about."

      ...and each year, astronomers, amateur and career, discover (some .. several) new and previously unknown "rocks" whose orbits CROSS that of the earth. I believe this year's count of such new discoveries, for rocks with radius > 5 km. is already on the order of 3.

      Oh, and about your moon-sized-rock: we already track everything bigger than a few kilometers. So, sure it might kill us, but we'll have a hundred years or so to think about it.

      And a few decades to think about being hit by a rock bigger the size of the Moon will make me feel better how?

      Sings "Anticipation...anticipa-a-ation..." while searching for his Carly Simon CD's

      emc

      "Being forced to write comments actually improves code, because it is easier to fix a crock than to explain it. "
      —G. Steele
        I see you shiver, with antici...

        say it, say it!

        ... pation.

        Sorry, we all have our anticipation references

      Somehow, this isn't altogether comforting. Even a fairly small rock, 1 or 2 km. in diameter, could ruin your whole day. At that size, huge clouds of dust would be spewed up, probably causing seriously cold weather for a few years. Also, it would adversely affect any city it landed on by annihilating it. Depending on which city it was, this might be considered a bad thing.