Decadal-scale modulation of the NAO/AO by external forcing: Current state of understanding

Shindell, Drew T. (2006) Decadal-scale modulation of the NAO/AO by external forcing: Current state of understanding. Il nuovo cimento C, 29 (1). pp. 137-145. ISSN 1826-9885

[img]
Preview
Text
ncc9166.pdf - Published Version

Download (548kB) | Preview
Official URL: https://www.sif.it/riviste/sif/ncc/econtents/2006/...

Abstract

Analyses of observations show correlations between the mean state of indices representing either the North Atlantic Oscillation (NAO) or the Arctic Oscillation (AO, also called Northern Annular Mode) with various external forcings. These include volcanic eruptions, solar variability, greenhouse gas levels and stratospheric ozone depletion. Climate model simulations have been able to reproduce many aspects of these correlations over a variety of time scales ranging from interannual to century scale. This has allowed some insight to be gained into how external forcings modulate these intrinsic variability patterns. I review current understanding derived from comparisons of a range of models with observations to highlight areas of commonality as well as remaining uncertainties. Contrasts between the Northern and Southern Hemispheres suggest that much of the response to external forcing occurs via wave-driven processes. Comparison of the response to forcings at different levels in the atmosphere indicate a sizeable role for both stratospheric and surface-level perturbations. Implications for forcing of changes in Mediterranean climate are presented for pre-industrial times during the last millennium, for the twentieth century, and for the potential future.

Item Type: Article
Additional Information: Paper presented at the Workshop on “Historical Reconstruction of Climate Variability and Change in Mediterranean Regions”, Bologna, October 5-6, 2004.
Uncontrolled Keywords: Climatology ; Climate dynamics ; General circulation
Subjects: 500 Scienze naturali e Matematica > 550 Scienze della Terra > 551.6 Climatologia e tempo atmosferico (Classificare qui i lo studio dei Cambiamenti climatici)
Depositing User: Marina Spanti
Date Deposited: 18 Mar 2020 16:25
Last Modified: 18 Mar 2020 16:25
URI: http://eprints.bice.rm.cnr.it/id/eprint/16054

Actions (login required)

View Item View Item