eCite Digital Repository

Drivers of decadal variability in the Tasman Sea


Sloyan, BM and O'Kane, TJ, Drivers of decadal variability in the Tasman Sea, Journal of Geophysical Research: Oceans, 120, (5) pp. 3193-3210. ISSN 2169-9275 (2015) [Refereed Article]


Copyright Statement

Copyright 2015 American Geophysical Union

DOI: doi:10.1002/2014JC010550


In this study, we compare optimally interpolated monthly time series Tasman Sea XBT data and a comprehensive set of ocean data assimilation models forced by atmospheric reanalysis to investigate the stability of the Tasman Sea thermocline and the transport variability of the East Australian Current (EAC), the Tasman Front, and EAC-extension. We find that anomalously weaker EAC transport at 25S corresponds to an anomalously weaker Tasman Front and anomalously stronger EAC-extension. We further show that, post about 1980 and relative to the previous 30 years, the anomalously weaker EAC transport at 25S is associated with large-scale changes in the Tasman Sea; specifically stronger stratification above the thermocline, larger thermocline temperature gradients, and enhanced energy conversion. Significant correlations are found between the Maria Island station Sea Surface Temperature (SST) variability and stratification, thermocline temperature gradient, and baroclinic energy conversion suggesting that nonlinear dynamical responses to variability in the basin-scale wind stress curl are important drivers of decadal variability in the Tasman Sea. We further show that the stability of the EAC is linked, via the South Caledonian Jet, to the stability of the pan-basin subtropical South Pacific Ocean "storm track."

Item Details

Item Type:Refereed Article
Keywords:variability, Tasman Sea, drivers, data assimilation, East Australian Current
Research Division:Earth Sciences
Research Group:Oceanography
Research Field:Physical oceanography
Objective Division:Environmental Management
Objective Group:Marine systems and management
Objective Field:Oceanic processes (excl. in the Antarctic and Southern Ocean)
UTAS Author:Sloyan, BM (Dr Bernadette Sloyan)
UTAS Author:O'Kane, TJ (Dr Terry O'Kane)
ID Code:118499
Year Published:2015
Web of Science® Times Cited:29
Deposited By:Directorate
Deposited On:2017-07-13
Last Modified:2017-10-16
Downloads:125 View Download Statistics

Repository Staff Only: item control page