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Any speculation on the giant polynya in the Beaufort Sea?

  1. Sep 22, 2006 #1

    A hole (polynya) the size of Indiana has opened in the Beaufort Sea, a part of the Arctic Ocean. Can anyone speculate on the the cause of this hole, the likes of which have not been witnessed before in this part of the Arctic?
  2. jcsd
  3. Sep 22, 2006 #2
  4. Sep 23, 2006 #3


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    This happens every year all the time doesn't it?
  5. Sep 23, 2006 #4
    Well you got to look all things simulaneously.


    One of the things that Richard Lindzen teaches is N-S heat distribution by ocean currents and atmosphere, levelling out temperature differences between arctic and tropics. So these two combined may suggest an increased interchange of heat. But of course, everything is global warming, so such a logical explanation is out of the question.
  6. Sep 23, 2006 #5
    True, polynyas are a natural and necessary part of sea ice dynamics. However, in terms of human observation, the size of this polynya is unprecedented.
  7. Sep 23, 2006 #6
    It's interesting, is it not, that this exceptionally large polynya has formed during an ocean cooling event.

    If Arctic Ocean waters are warming, as NASA has claimed (http://www.nasa.gov/centers/goddard/earthandsun/arctic_changes.html), would that not slow the heat exchange between the tropics and the poles, with the attendant weakening of atmospheric circulation, alteration of storm tracks, and alteration of temperature and pressure patterns, as suggested in the article I just referenced by NASA?

    Also, I would like to have a better understanding of the apparent synchronicity of increased ice melting at the poles, and shallow ocean water cooling. Is it possible there could be some linkage? Maybe you could enlighten me.
  8. Sep 23, 2006 #7
    We may be looking at a cyclic event here. For some odd reason in the chaos of ocean currents, there could be an increase in (subsurface?) flows towards the poles, upwelling somewhere to form polynyas, then there would also be a compensating flow back to the tropics, cooling it and perhaps suppressing hurricanes to form. Just thinking out loud.

    Then in a second stadium, the tropics pole temperature gradient having decreased, those flows may reduce again, resulting indeed in cooling poles and heating tropics again, closing the cycle.

    Coming to think of that, testing that idea, the clear temperature spike of the Arctic around 1940 AD about the same as today, may have caused a clear reduction in tropical storms. We should be able to find that out

    (link did not work properly though)
  9. Sep 23, 2006 #8
    A quick google brought me this;

    Clearly not a reduction.
    Last edited: Sep 23, 2006
  10. Sep 24, 2006 #9
  11. Sep 24, 2006 #10
    Have you counted this years Hurricanes? and weren't we talking about polynya of today? Not 2005.

    Interesting thought, althought the influence of oceanism volcanism may be overestimated considering the immense volumes of water and the huge amount of heat required.
  12. Sep 24, 2006 #11
    Undersea volcanic activity in the Arctic Ocean occurs along the Gakkel Ridge, the slowest spreading mid-ocean ridge currently known. However, this is not close to the Beaufort Sea.

  13. Sep 27, 2006 #12
    You suggested that there may have been reduced hurricane activity around 1940, I simply checked and found that it was not the case. The period 1941-1950 holds the record for the most major storms making landfall.

    Records are not as comprehensive before 1940, but here is a record of Atlantic hurricanes since then.

    182 / 30 = 6.07 hurricanes per year

    123 / 25 = 4.92 hurricanes per year

    69 / 9 = 7.66 hurricanes per year

    add 2004 and 2005 9 and 14

    92 / 11 = 8.36

    We seem to definately be in an increased Atlantic hurricane cycle. Note that the category 3 and higher have dramatically increased.

    Since the 2006 season is not complete, I don't see any reason to include it.
    Last edited: Sep 27, 2006
  14. Sep 27, 2006 #13


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  15. Sep 27, 2006 #14
    The oceans have warmed during the past 20 years. the ice is thinner and therefore more susceptible to warm upwelling. Once the ice is gone the suns radiation would be absorbed by the water, further warming the polynya and causing it to grow.

    As the earth warms, especially in the Arctic, we should expect to see more of this.
  16. Sep 27, 2006 #15
    That must be an old graph, 2004 had 9 hurricanes in the Atlantic. Gaston was not originally categorized as a hurricane, but was subsequently upgraded.


    Here is a more recent graph

  17. Oct 4, 2006 #16
    There's one big problem (as has already been mentioned) with older data: it's incompleteness. That's why the NOAA also has a table of only landfalling US hurricanes here:


    If you graph that (and adjust the period 2001-2004 by a factor of 10/4), it looks like this:


    It's actually not fair, because the NOAA estimates SE Florida records (even for landfalling hurricanes) are complete only after 1900 (the area was very thinly populated). Note that 2005 was very active, but 2006 (admittedly not done yet) is right on average so far this season (and therefore very inactive for the 2001-2004 data group). If you include both, the graph looks about the same.

    There's something callled the "Atlantic Multi-decadal Oscillation" that reinsurers have been worrying about for two decades now. The NOAA has a few FAQs on it. Current variations in hurricane frequency fall well within the potential limits of the AMDO. You don't need global warming at all to explain the current increase. Occam's Razor applies.
    Last edited: Oct 4, 2006
  18. Oct 4, 2006 #17
    Here's the NOAA FAQ on the AMO, BTW (gee, do you think I could get any more acronyms in that?):


    There's other pages on NOAA that say the AMO is the sole driver, and some that say global warming is a contributing factor. That FAQ seems about the middle of the road.
  19. Oct 5, 2006 #18


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    Staff: Mentor

    That's very interesting, thanks for the link!
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