Global Correlations with the NAO Index

NAO vs. Winter Temperature

NAO vs. WInter TEMP

NAO vs. Winter Precipitation

NAO vs. WInter PRCP

winter is defined as DJFM

The NAO was first described in the diaries of the missionary Hans Egede Saabye as a see-saw in temperature between Greenland and Denmark (Saabye, 1942). The NAO was later defined by Sir Gilbert Walker as "the tendency for pressure to be low near Iceland in winter when it is high near the Azores and south-west Europe" (Walker, 1924;Walker and Bliss, 1932). Accounting for more than 1/3 of the total variance of the sea level pressure (SLP) field over the North Atlantic, the NAO is most pronounced during the winter months (December through March)due to an increased sea air temperature contrast (Barnston and Livezey, 1987).

  1. Meridional pressure gradient driving mid-latitude westerlies
  2. Quantifying the climate impacts of the NAO
  3. Interdecadal variations in North Atlantic SST's
  4. The NAO and thermohaline circulation: a damped oscillator
  5. Defining indices to track the NAO


The NAO can be seen through the lens of several environmental variables. Figure 1 (figure caption) depicts these various manifestations in terms of sea-level pressure (SLP), storm-tracks, sea surface temperature (SST), temperature and precipitation.



Maintained by:

Heidi Cullen
Lamont-Doherty Earth Observatory
Palisades, NY 10964