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Global warming causes great cooling

  1. Mar 24, 2007 #1


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    I've seen it before that some people say that global warming will cause or does now cause areas to greatly cool as well. How is this true?
  2. jcsd
  3. Mar 24, 2007 #2
    Last edited: Mar 24, 2007
  4. Mar 24, 2007 #3

    D H

    Staff: Mentor

    Some people (i.e., Rush Limbaugh) have a mistaken perception that "global warming" means the entire Earth is getting hotter. Global warming simply means that the average temperature over the course of one year and over the entire surface of the Earth is increasing. The average temperature can rise even if some places get colder because this drop is more than compensated by a rise elsewhere.

    There are several hypothetical mechanisms that might well trigger some places to get a lot colder because of global warming. For example, global warming could result in a massive release of melted (but still very cold) water from Greenland into the Atlantic. This could shut down the Gulf Stream, making Northern Europe get very cold. This shutdown in turn would make the Gulf of Mexico area get very hot (as if its not hot enough down here already). Some of these hypothetical mechanisms even suggest that global warming might well trigger the next Ice Age.
  5. Mar 24, 2007 #4
  6. Mar 26, 2007 #5

    Seager's findings are very interesting and I'm sure they will continue to recieve study. But the standard explanation isn't a myth or a "falsified hypothesis" by any means. Seager has an interesting, and controversial, view. His work isn't something new that's revolutionized climatologists' understanding; it's been around for a few years and is well known.

    I live near Victoria, and of course it doesn't have a gulf stream, because the gulf stream is in the Atlantic. Our ocean currents are part of the North Pacific Gyre, which transports heat from the tropics. The principle is exactly the same. The offshore winds are warm because the ocean is warm.

    I can't help but be struck by his description of wind patterns over the Rocky Mountains. The Rockies aren't even in the equation. The mild climate is limited to a narrow strip of coastline far from the Rockies. However, he may be referring to the Coast Range, which borders almost the whole of the western Canadian coast and the Alaska Panhandle. But why is the effect more pronounced in Britain than in western North America? Western Europe is certianly less mountainous. Windmill palms are grown on the isles of western Scotland. They grow in areas of the Canadian Pacific coast as well, but at lower latitudes. I belive the standard explanation is that the Gulf Stream is stronger than the North Pacific Gyre.

    As for the areas east of the mountains, in Canada at least, they are only cold in winter. That cold is due to winds from the north, not from the west, and it extends surprisingly far south. In summer, the Canadian prairies get much hotter than the west coast.

    I'm not taking issue with Seager's theory per se. He's the scientist, not me. Or you, for that matter. He may be right. Or partly right. Neither of us is able to honestly make that assessment. I'm just pointing out that his findings are not completely accepted and don't answer all the questions. They're interesting enough, but they don't justify dismissing the standard model as a myth.
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