Mobility of the North Atlantic Oscillation Since the 1820s
Abstract
The North Atlantic Oscillation (NAO) is one of the most important modes of variability in the global climate system and is characterized by a dipole in the sea-level pressure field with centers-of-action near Iceland and the Azores. It has a profound influence on the weather, climate, ecosystems and economies of Europe, Greenland, eastern North America and North Africa. It has been proposed that around 1980 there was an eastward secular shift in the NAO’s northern center-of-action. Independently it has also been suggested that the location of its southern center-of-action is tied to the phase of the NAO. Both of these attributes have been linked to anthropogenic climate change. In this paper, we revisit one of the classical techniques developed to characterize the structure of the NAO with a longer and more robust set of atmospheric fields than has been used before. We show that there exists simultaneous mobility in both centers-of-action and argue that this mobility is periodic in nature. We argue that this mobility has a profound impact on the regions of the atmosphere and ocean that are affected by the NAO.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2010
- Bibcode:
- 2010AGUFM.A34B..03M
- Keywords:
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- 3309 ATMOSPHERIC PROCESSES / Climatology;
- 3349 ATMOSPHERIC PROCESSES / Polar meteorology;
- 3364 ATMOSPHERIC PROCESSES / Synoptic-scale meteorology