eCite Digital Repository

Low frequency variability in an coupled ocean-sea ice general circulation model of the Southern Ocean


O'Kane, TJ and Matear, R and Chamberlain, MA and Risby, JS and Horenko, I and Sloyan, BM, Low frequency variability in an coupled ocean-sea ice general circulation model of the Southern Ocean, ANZIAM Journal, 54, (SUPPL) pp. C200-C216. ISSN 1446-1811 (2012) [Refereed Article]

Copyright Statement

Copyright 2013 Austral. Mathematical Soc.

DOI: doi:10.21914/anziamj.v54i0.6178


A coupled ocean-sea ice general circulation model is used to identify a Southern Ocean southeast Pacific intrinsic mode of low frequency variability and its response to inter-annual atmospheric forcing. Using forcing data from the co-ordinated ocean-ice reference experiment, a comprehensive suite of experiments elucidated excitation and amplification mechanisms of this intrinsic mode by low frequency forcing and stochastic forcing due to high frequency winds. Subsurface thermocline anomalies are found to teleconnect the Pacific and Atlantic regions of the Antarctic circumpolar current (ACC). It is found that the Pacific region of the ACC is characterised by intrinsic baroclinic disturbances that respond to both zonal and latitudinal wind variations, while the Atlantic sector of the ACC is sensitive to higher frequency synoptic winds that act to amplify thermocline anomalies propagating downstream from the Pacific resonant with eastward travelling Rossby waves. This simulation study identifies plausible mechanisms that determine the predictability of the Southern Ocean climate on multi-decadal timescales.

Item Details

Item Type:Refereed Article
Keywords:forced and low frequency ocean modes, intrinsic
Research Division:Earth Sciences
Research Group:Oceanography
Research Field:Physical oceanography
Objective Division:Environmental Management
Objective Group:Management of Antarctic and Southern Ocean environments
Objective Field:Antarctic and Southern Ocean oceanic processes
UTAS Author:O'Kane, TJ (Dr Terry O'Kane)
UTAS Author:Matear, R (Dr Richard Matear)
UTAS Author:Sloyan, BM (Dr Bernadette Sloyan)
ID Code:118949
Year Published:2012
Deposited By:Ecology and Biodiversity
Deposited On:2017-07-24
Last Modified:2017-08-18

Repository Staff Only: item control page