by A. May, July 18, 2025 in WUWT

ow) but they are not the same. The NAO is usually measured using the SLP (sea level air pressure) difference between the Azores or the Iberian Peninsula and Iceland and is a North Atlantic regional phenomenon, whereas the Arctic Oscillation is the SLP difference between the northern mid-latitudes and the Arctic, and is evident in all longitudes (Thompson & Wallace, 2001). The AO accounts for more of the variance in Northern Hemisphere surface air temperature than the NAO and is tightly connected to the stratospheric polar vortex (Higgins, et al., 2000) and (Thompson & Wallace, 1998). We will discuss these oscillations together in this post.

The Arctic Oscillation

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