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Statistical analysis that warmer oceans caused the crazy hurricains last year

  1. Mar 23, 2006 #1
  2. jcsd
  3. Mar 23, 2006 #2


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    Well, it is pretty hard to say with certainty that one event was 'caused' by a specific factor. The Atlantic Ocean, Caribbean Sea and Gulf of Mexico were apparently slightly warmer than in the past, and we did have two powerful hurricanes. While there appears to be a correlation, it doesn't necessarily indicate a cause and effect relationship, but that could very well be the case.

    The big question is then - is this an anomaly, or is this a trend? If it is a trend, then we should expect more such devastating events in the near term.

    Certainly the insurance industry is concerned.
  4. Mar 23, 2006 #3
    Boo this article! :grumpy:

    Here's a little question somebody had about the strange glow they saw in the eye of a hurricane:

    Is warm water the only contributing factor? No, but it helps.
  5. Mar 23, 2006 #4


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    "The link between rising ocean temperatures and overall climate change remains murky because of the overlap between natural cycles and any global warming. "But if you buy the argument that global warming is causing the increase in sea surface temperatures--and everybody seems to be buying this--then it's a pretty small leap to say global warming is causing this increase [in hurricane frequency]," Curry says."

    Says it all --- "But, Mom, everybody else is doing it."
  6. Mar 23, 2006 #5


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    It was caused by variations in the Atlantic multidecadal oscillation. There was also wind shear, and warmer winds coming from Africa that were more favorable for cyclone formation in the Atlantic.

    http://en.wikipedia.org/wiki/Atlantic_Multidecadal_Oscillation#Relation to Atlantic hurricanes

  7. Mar 24, 2006 #6
  8. Mar 24, 2006 #7


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    No it doesn't, its a crack site.

    Last edited: Mar 24, 2006
  9. Mar 27, 2006 #8


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    This article didn't link rising temperatures to the hurricanes last year. In fact, it said that locally and within single season, plenty of other variables play just as significant a role. It's only globally and over the last 35 years that they've been able to isolate rising surface temperatures as the only trend. Wind shear, wind variation, and specific humidity haven't been trending upward over 35 years (I'm not even sure they could), but they certainly could have contributed to last year's abnormal season.

    All in all, the title of this thread is a little misleading, since the article doesn't actually make that claim.
  10. Apr 10, 2006 #9
    I think the number of cyclones ejecting from the "african train" was about average and that combined with little pacific tampering (no El Nino) allowed most of them to develop into storms. But it should be noted that what was particularly astounding about last hurricane season was the number of storms that became strong enough to be named and that is directly related to warm water temperatures.

    Also, I would be careful about saying that it was caused by AMO because these "oscillations" are really only visible with Fourier decompositions on SST data that is relatively small in size (150 years I think). And the fact that there is a dominant frequency in a small finite data set does not imply that the population from which the data set belongs actually has any periodicity to it at all. Though, I agree that warm water does allow storms to strengthen more.
    Last edited: Apr 10, 2006
  11. Apr 11, 2006 #10


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    Hey dand, welcome to Physicsforums!

    I don't see how El Niño "allowed most of them to develop into storms."
  12. Apr 12, 2006 #11
    Hi Mk, thanks for the welcome.

    But I don't think I said that El Nino allowed them to develop into storms, what I said was that the absence of an "El Nino"/other pacific signals did not prevent them from developing into significant storms.
  13. Apr 13, 2006 #12


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    So what affect does Pacific El Niño have on Atlantic cyclone formation?
  14. Apr 13, 2006 #13
    Statistically fewer atlantic cyclones mature into tropical storms during pacific El Ninos.


    Theoretically, El Nino episodes increase vertical wind shear and hence turbulence which distort and mix out the latent heat release from developing cyclones over a larger distorted area thereby weakening the storms. I have heard people refer to this as "tearing or shearing apart the storms."
  15. May 20, 2006 #14
    Then how do you explain Hurricane Vince which developed into a hurricane over water that was under 80 F or 26 C?

    Attached Files:

  16. May 20, 2006 #15
    The discussion on the site is questionable, but the basic concept of the "dry tongue" or cold arctic air makes sense. The term "dry tongue" is used on some noaa pages, but doesn't seem to be the preferred term. Cold air aloft, which will be dry because it cannot hold much water, does play a role in storms. One of our worst years for tornadoes and large hail in Kansas occurred when we had a large area of unusually cold air from Siberia over the state.

    Storms occur not because of a "short circuit" but because the basic mixing of warm moist air and cold dry air creates an explosive situation.
  17. May 21, 2006 #16


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    Presuming that the "African train" are easterlies coming from North Africa, they are not the main cause, but create more favorable conditions for cyclone development.
  18. Feb 15, 2007 #17
    I am new to the site, so I am a little late to the discussion, to my benifit :smile:

    Judging by the lack of Hurricanes last season ( 2006) there is no direct connection to the A.G.W. debate.

    From http://www.cnn.com/2006/WEATHER/11/30/hurricanes/index.html

    Last edited: Feb 15, 2007
  19. Feb 16, 2007 #18
    The current El Nino has been predicted by late Theodore Landscheidt in 2003:


    This El Nino became apparant in Aug-Sept 2006, which should strenghten his ideas about the solar cycles and it's effect on climate.

    It should be noted that there were also no hurricanes before El Nino.
    Last edited: Feb 16, 2007
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