OS Ocean Science OS Ocean Sci. 1812-0792 Copernicus Publications Göttingen, Germany 10.5194/os-6-143-2010 Transformation of an Agulhas eddy near the continental slope Baker-Yeboah S. 1 Flierl G. R. 1 Sutyrin G. G. 2 Zhang Y. 1 Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology,Cambridge, MA 02139, USA Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island 02882, USA 02 02 2010 6 1 143 159 Copyright: © 2010 S. Baker-Yeboah et al. 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://os.copernicus.org/articles/6/143/2010/os-6-143-2010.html The full text article is available as a PDF file from https://os.copernicus.org/articles/6/143/2010/os-6-143-2010.pdf

The transformation of Agulhas eddies near the continental slope of southern Africa and their subsequent self-propagation are analyzed in both observational data and numerical simulations. Self-propagation results from a net dipole moment of a generalized heton structure consisting of a surface-intensified anticyclonic eddy and deep cyclonic pattern. Such Agulhas vortical structures can form near the retroflection region and further north along the western coast of southern Africa. We analyze nonlinear topographic wave generation, vortex deformations, and filament production as an important part in water mass exchange. Self-propagating structures provide a conduit for exchange between the deep ocean and shelf regions in the Benguela upwelling system.

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