Journal cover Journal topic
Ocean Science An interactive open-access journal of the European Geosciences Union
Ocean Sci., 9, 773-785, 2013
© Author(s) 2013. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
05 Sep 2013
Impact of the Indonesian Throughflow on Agulhas leakage
D. Le Bars, H. A. Dijkstra, and W. P. M. De Ruijter
IMAU, Utrecht University, P.O. Box 80.005, 3508 TA Utrecht, the Netherlands

Abstract. Using ocean models of different complexity we show that opening the Indonesian Passage between the Pacific and the Indian oceans increases the input of Indian Ocean water into the South Atlantic via the Agulhas leakage. In a strongly eddying global ocean model this response results from an increased Agulhas Current transport and a constant proportion of Agulhas retroflection south of Africa. The leakage increases through an increased frequency of ring shedding events. In an idealized two-layer and flat-bottom eddy resolving model, the proportion of the Agulhas Current transport that retroflects is (for a wide range of wind stress forcing) not affected by an opening of the Indonesian Passage. Using a comparison with a linear model and previous work on the retroflection problem, the result is explained as a balance between two mechanisms: decrease retroflection due to large-scale momentum balance and increase due to local barotropic/baroclinic instabilities.

Citation: Le Bars, D., Dijkstra, H. A., and De Ruijter, W. P. M.: Impact of the Indonesian Throughflow on Agulhas leakage, Ocean Sci., 9, 773-785, doi:10.5194/os-9-773-2013, 2013.
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