South African Journal of Science
On-line version ISSN 1996-7489
WHITTLE, C.; LUTJEHARMS, J.R.E.; DUNCOMBE RAE, C.M. and SHILLINGTON, F.A.. Interaction of Agulhas filaments with mesoscale turbulence: a case study. S. Afr. j. sci. [online]. 2008, vol.104, n.3-4, pp. 135-139. ISSN 1996-7489.
The inter-ocean leakage of heat and salt from the South Indian Ocean to the South Atlantic has important consequences for the global thermohaline circulation and in particular for the strength of overturning of the Atlantic Ocean as a whole. This leakage between these two subtropical gyres takes place south of Africa. The main mechanisms are the intermittent shedding of Agulhas rings from the retroflection of the Agulhas Current and the advection of Agulhas filaments from the border of the Agulhas Current, both of which move northwestward into the South Atlantic. The subsequent behaviour and mixing of Agulhas rings has been much studied over the past years, that of Agulhas filaments not at all. We report here on fortuitous hydrographic observations of the behaviour of an Agulhas filament that interacted with a number of mesoscale features shortly after formation. This suggests that Agulhas filaments may be involved in many other circulation elements and not only the Benguela upwelling front, as was surmised previously, and may mix out in a very site-specific region.