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Why Do Hurricanes Always Rotate Counter Clockwise?

  1. Sep 10, 2004 #1
    Down here in Florida we are about to see our THIRD HURRICANE OF THE SEASON. Unbelievable is the chaos that is going on. :eek:

    Anyway, just wondering what causes a hurricane to rotate counter clockwise?

    Jason
    SW Florida
    Hurricane Charley, Hurricane Frances, & approaching Hurricane Ivan
    http://thealdens.org
     
  2. jcsd
  3. Sep 10, 2004 #2
    The folllowing is from the NOAA website's Hurricane Research Center.

    Why do tropical cyclones' winds rotate counter-clockwise (clockwise) in the Northern (Southern) Hemisphere?

    The reason is that the earth's rotation sets up an apparent force (called the Coriolis force) that pulls the winds to the right in the Northern Hemisphere (and to the left in the Southern Hemisphere). So when a low pressure starts to form north of the equator, the surface winds will flow inward trying to fill in the low and will be deflected to the right and a counter-clockwise rotation will be initiated. The opposite (a deflection to the left and a clockwise rotation) will occur south of the equator

    The question came up in Astronomy Class. The instructor emphatically stressed that Coiollis force doest affect the whirlpools that form in the sink. :biggrin:
     
  4. Sep 10, 2004 #3

    Nereid

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    Actually, it does. However, it's so weak that most any other, random force will be greater, so sink whirlpools don't have a tendency to be clockwise or anti-clockwise, no matter where they are.
     
  5. Sep 10, 2004 #4

    Tide

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    That sounds like the definition of "does not have an effect!"
    :smile:

    Even without the other "random forces" the effect would be so small it would not be noticeable.
     
  6. Sep 10, 2004 #5

    Nereid

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    effecting an affectation?

    Yes, I agree :approve:

    [nitpick] However, H bar-None's words are: "doest affect the whirlpools that form in the sink". Affecting whirlpools is quite different - though related - to having an effect on them! [/nitpick]
     
  7. Sep 10, 2004 #6
    Hurricanes get some of their energy from warm moist air near the equator, and as they move away from the equator,
    to conserve angular momentum (as they get closer to the Earth's spin axis),
    they move faster relative to the sea and become even more devastating.
     
  8. Sep 10, 2004 #7

    Janus

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    Actually sounds more like the definition of "does not have a measureable effect!."
     
  9. Sep 10, 2004 #8

    Tide

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    I can live with that! :-)
     
  10. Sep 11, 2004 #9

    Ivan Seeking

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    A funny side note. Someone that I met once observed that many toilets made in South America are jetted the opposite direction to the good old Crane et al. toilets here in the US. I bet this has helped to perpetuate the myth about whirlpools. People have in fact seen toilets that create a reverse whirlpools in SA, as compared to NA.
     
  11. Sep 11, 2004 #10
    I had a long argument with my geography teacher over the whirlpools that form when you flush some toilets. I read from a credible source that the direction of the whirlpool depends more on the shape of the toilet bowl than the Coriolis effect.
     
  12. Sep 11, 2004 #11
    Is this proper?

    "Actually sounds more like the definition of 'does not have measureable effect!."'
     
  13. Sep 11, 2004 #12

    russ_watters

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    That's what they were saying above - in your toilet, water isn't sent in straight down, its sent in jets to create a wirlpool (to make sure water cleans the entire bowl instead of just running down the sides). The wirlpool goes in whatever direction the water jets push it - and thats a design issue. If the designer of sent the jets in the other direction, it would still work time.
     
  14. Sep 11, 2004 #13

    LURCH

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    can a huricane or cyclone form on the equator? Without Coriolis, it won't organise, will it?
     
  15. Sep 12, 2004 #14
    I don't think that the Coriolis Force can affect WCs whirlpool... it must be a very low effect
     
  16. Sep 12, 2004 #15
    yaaaa, go simpsons. The toilet in australia on the americal embasy is made to go counter clockwise just like in the states.
     
  17. Sep 12, 2004 #16
    Would we call this a "Hurriclone"?

    On the same note, it would be interesting to see how a hurricane would cross the equator.
     
  18. Sep 12, 2004 #17

    LURCH

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    I think so too. I'm betting it just gets scrambled and dissapates. Perhaps if the depression is strong enough to persist, the storm would reform rotating in the opposite duirection. Thing is, I can't think of a single case where a storm of this sort has crossed the equator. Anybody heard of one? I mean, it would seem unlikely, as the Earth's rotation would tend to draw a storm away from the equator, but it isn't impossible, is it?
     
  19. Sep 13, 2004 #18
    Maybe so, I am not sure.
     
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