Sources, fate, and pathways of Leeuwin Current water in the Indian Ocean and Great Australian Bight: A Lagrangian study in an eddy-resolving ocean model
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Accepted version
Author(s)
Yit Sen Bull, C
van Sebille, E
Type
Journal Article
Abstract
The Leeuwin Current is the dominant circulation feature in the eastern Indian Ocean, transporting tropical and subtropical water southward. Whilst it is known that the Leeuwin Current draws its water from a multitude of sources, existing Indian Ocean circulation schematics have never quantified the fluxes of tropical and subtropical source water flowing into the Leeuwin Current. This paper uses virtual Lagrangian particles to quantify the transport of these sources along the Leeuwin Current's mean pathway. Here, the pathways and exchange of Leeuwin Current source waters across six coastally bound sectors on the south-west Australian coast are analysed. This constitutes the first quantitative assessment of Leeuwin Current pathways within an offline, 50-year integration time, eddy-resolving global ocean model simulation. Along the Leeuwin Current's pathway we find a mean poleward transport of 3.7 Sv in which the tropical sources account for 60-78% of the transport. Whilst the net transport is small, we see large transports flowing in and out of all the offshore boundaries of the Leeuwin Current sectors. Along the Leeuwin Current's pathway, we find that water from the Indonesian Throughflow contributes 50-66% of the seasonal signal. By applying conditions on the routes particles take entering the Leeuwin Current, we find particles are more likely to travel offshore north of 30°S, while south of 30°S particles are more likely to continue downstream. We find a 0.2 Sv pathway of water from the Leeuwin Current's source regions, flowing through the entire Leeuwin Current pathway into the Great Australian Bight.
Date Issued
2016-02-05
Date Acceptance
2016-02-01
Citation
Journal of Geophysical Research: Oceans, 2016, 121 (3), pp.1626-1639
ISSN
2169-9291
Publisher
Wiley
Start Page
1626
End Page
1639
Journal / Book Title
Journal of Geophysical Research: Oceans
Volume
121
Issue
3
Copyright Statement
This is the peer reviewed version of the following article: Yit Sen Bull, C., and E. van Sebille (2016), Sources, fate, and pathways of Leeuwin Current water in the Indian Ocean and Great Australian Bight: A Lagrangian study in an eddy-resolving ocean model, J. Geophys. Res. Oceans, 121, 1626–1639, which has been published in final form at https://dx.doi.org/10.1002/2015JC011486. This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.
Sponsor
Australian Research Council
Grant Number
DE130101336
Subjects
Science & Technology
Physical Sciences
Oceanography
WESTERN-AUSTRALIA
INDONESIAN THROUGHFLOW
TASMAN LEAKAGE
CURRENT SYSTEM
CAPES CURRENT
DYNAMICS
EDDIES
PACIFIC
COUNTERCURRENT
VARIABILITY
Publication Status
Published