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Are we going through a negative phase of the Atlantic Multidecadal Oscillation (AMO)

  • 22-12-2016 11:57am
    #1
    Closed Accounts Posts: 4,559 pedigree 6


    As the title suggests are we going through a negative phase of the Atlantic Multidecadal Oscillation (AMO) at present?

    The reason I ask is we have extreme cold in parts of the U.S at present and usually that would mean a turbo charged Jetstream turned on over the North Atlantic.
    But what is happening? A Jet that is just barely reaching Ireland and storms that would hit us in a strong jet are going north missing us completely (not that we want them). Then further out it looks like high pressure is going to build over us from Europe and even move out over us into the North Atlantic.
    It's like the North Atlantic has no influence on our weather this year.

    So is it negative or positive?


Comments

  • Closed Accounts Posts: 4,559 pedigree 6


    Not sure what the answer is.

    But we have to look at what events that stand out occurred this year.
    This would be the big one for me.
    http://www.noaa.gov/media-release/unprecedented-arctic-warmth-in-2016-triggers-massive-decline-in-sea-ice-snow

    All that extra freshwater in the North Atlantic is bound to affect the Thermohaline circulation.
    https://en.wikipedia.org/wiki/Thermohaline_circulation

    So what to expect or is this a year only event?


  • Banned (with Prison Access) Posts: 1,141 Stealthfins


    Off shore wind's and big Atlantic swells ?


  • Closed Accounts Posts: 4,559 pedigree 6


    Off shore wind's and big Atlantic swells ?

    Not sure I kind of understand your question.
    But it's like from this summer on, that just barely the west coast of Ireland got any influence from Atlantic weather.
    It's like the high pressure that normally benefits the southeast of England was 400 miles west this year?

    Or maybe the question should be why is high pressure so prominent this autumn/winter?
    Or maybe it's a combination of both?


  • Closed Accounts Posts: 4,559 pedigree 6


    Just comparing sea temperature anomalies for this year and last year.

    This week 2016.
    screenshot_1.png

    Same week 2015.
    screenshot_1.png
    (Images courtesy of NOAA).

    Biggest difference globally is El Nino conditions last year and a prominent La Nina this year.
    Also a bigger difference between the cooler and warmer anomalies in the North Atlantic last year.
    (Well also a big cold pool of water between Russia and Canada in the North Pacific).


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