Ocean Science www.ocean-sci.net 1812-0784 1812-0792 5 4 2009 10.5194/os-5-511-2009 http://www.ocean-sci.net/5/511/2009/ http://www.ocean-sci.net/5/511/2009/os-5-511-2009.html http://www.ocean-sci.net/5/511/2009/os-5-511-2009.pdf 511 521 2009-11-03 Relating Agulhas leakage to the Agulhas Current retroflection location E. van Sebille e.vanSebille@uu.nl C. N. Barron A. Biastoch P. J. van Leeuwen F. C. Vossepoel W. P. M. de Ruijter Institute for Marine and Atmospheric Research Utrecht, Utrecht University, The Netherlands Naval Research Laboratory, Stennis Space Center, Mississippi, USA Leibniz Institute of Marine Sciences, Kiel, Germany SRON Netherlands Institute for Space Research, Utrecht, The Netherlands now at: Department of Meteorology, University of Reading, UK now at: Shell International Exploration and Production B.V., Rijswijk, The Netherlands The relation between the Agulhas Current retroflection location and the magnitude of Agulhas leakage, the transport of water from the Indian to the Atlantic Ocean, is investigated in a high-resolution numerical ocean model. Sudden eastward retreats of the Agulhas Current retroflection loop are linearly related to the shedding of Agulhas rings, where larger retreats generate larger rings. Using numerical Lagrangian floats a 37 year time series of the magnitude of Agulhas leakage in the model is constructed. 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