Winter '12 / '13 - Arctic Oscillation: New Record for March



Rockefeller Center - NYC
09-FEB-69
(FEB-69 AO:  -1.325; MAR-69 AO:  -2.084)

 The MAR-13 AO of -3.176 crushes the old record of -2.848 set 51 years ago in 1962.

The last time the March AO went below -1 was in 2006.

The last time the March AO tanked below -2 was in 1984.

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The AO for the preceding meteorological winter (D-J-F) averaged -1.122.

The AO/s 5-year moving average during meteorological winter is -0.909

The AO during meteorological winter has been negative...
....four of the last five seasons (average = -0.413)
...nine of the last 10 seasons (average = -0.368)
...12 of the last 15 seasons (average = -0.255)

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Not that any of these trends are abnormal.
The 5-year moving average was negative during the vast majority of the time between mid-50s to late '80s.  The abnormal 'positive ' period occurred between 1989 and 1996.

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Monthly AO data here.