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M. Krug et al.
Fig. 12.1 The Agulhas current region. ODYSSEA SST with overlaid AVISO absolute geostrophic
currents on 21 November 2010
northern Agulhas Current located between 26
◦ S and 34
◦ S where the current flows in
close proximity to the coast, the southern Agulhas Current (east of the Agulhas Bank)
where the Agulhas Current detaches from a wider continental slope, and the Agulhas
Retroflection, between 36
◦ S and 40
◦ S, where the current undergoes a sudden change
of direction (Lutjeharms 2006). Like other western boundary currents, the Agulhas
Current is an intense and narrow flow characterised by strong velocity gradients
and a central warm core, with isopycnal lines sloping steeply towards the coast
(Goschen and Schumann 1990; Casal et al. 2009; Bryden et al. 2005). Thermal and
sea level surface signatures associated with the Agulhas Current enable the mapping
of the Agulhas Current’s path from space, using observations of Sea Surface Height
(SSH) from altimeters and Sea Surface Temperature (SST) from radiometers (see
e.g. Fig. 12.1).