Open AccessMechanisms of Decadal Arctic Climate Variability in the Community Climate System Model, Version 2 (CCSM2)
Author(s) -
Hugues Goosse,
Marika M. Holland
Publication year - 2005
Publication title -
journal of climate
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.315
H-Index - 287
eISSN - 1520-0442
pISSN - 0894-8755
DOI - 10.1175/jcli3476.1
Subject(s) - climatology , arctic dipole anomaly , arctic , environmental science , anticyclone , forcing (mathematics) , arctic geoengineering , north atlantic oscillation , arctic oscillation , climate change , climate model , atmospheric circulation , arctic ecology , arctic sea ice decline , oceanography , geology , arctic ice pack , northern hemisphere , sea ice thickness , drift ice , antarctic sea ice
Several mechanisms have been proposed to explain natural climate variability in the Arctic. These include processes related to the influence of the North Atlantic Oscillation/Arctic Oscillation (NAO/AO), anticyclonic/cyclonic regimes, changes in the oceanic and atmospheric North Atlantic-Arctic exchange, and changes in the Atlantic meridional overturning circulation. After a brief critical review, the influence and interrelation of the above processes in a long climate integration of the Community Climate System Model, version 2 (CCSM2) are examined. The analysis is based on the time series of surface air temperature integrated northward of 70 degrees N, which serves as a useful proxy for general Arctic climate conditions. This gives a large-scale view of the evolution of Arctic climate. It is found that changes in oceanic exchange and heat transport in the Barents Sea dominate in forcing the Arctic surface air temperature variability in CCSM2. Changes in atmospheric circulation are consistent with a wind forcing of this variability, while changes in the deep overturning circulation in the Atlantic are more weakly related in CCSM2. Over some time periods, the NAO/AO is significantly related to these changes in Arctic climate conditions. However, this is not robust over longer time scales