The North Atlantic Oscillation 1959-1998 : a data study

• Main Author: Petriello, Paolo, 1975-
• Other Authors: Derome, Jacques (advisor), Lin, Charles (advisor)
• Format: Thesis
• Language: English
• Published: McGill University 1999
• Subjects: Physics; Atmospheric Science; Baffin Island; Barents Sea; Greenland; Norwegian Sea; Baffin; North Atlantic; North Atlantic oscillation
• Online Access: http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30724

The North Atlantic Oscillation (NAO) refers to a low-frequency mode of atmospheric variability with two centres of action in the pressure field. The present study examines various atmospheric fields associated with the NAO. The NCEP/NCAR reanalysis data set from 1958--1998 is used. We find that the NAO-positive (NAO-negative) phase induces: (i) anomalously high (low) winter mean sea-level pressure (SLP) in the Azores High region and anomalously low (high) SLP in the Icelandic Low region; (ii) anomalously high (low) winter mean temperatures over northern Eurasia and anomalously low (high) temperatures over northwestern Africa, Greenland, and segments of northeastern North America (i.e., primarily northern Quebec, Labrador, and Baffin Island); and (iii) anomalously high (low) winter mean preapitation centred over the Norwegian Sea/Barents Sea region and anomalously low (high) precipitation over southern Europe, western Greenland, and the above-mentioned region in northeastern North America. Also, it is shown that the variability in storm track position and intensity due to the NAO is largely responsible for the European NAO-induced precipitation anomalies.