During the winter of 1999, eleven drifters were deployed over the Benguela shelf to explore large-scale transport of surface waters. Half of the drifters were deployed 'nearshore' (over the mid-shelf) and the other half 'offshore' (over the outer shelf). Nearshore drifters exhibited onshore movement at all latitudes and poleward flow at southern latitudes (33-34 degreesS). Offshore drifters moved equatorward at speeds of 0.05-0.3 m s(-1), roughly following isobaths over the shelf. Discontinuities in along-shelf transport were observed at the Angola-Benguela Front (16-17 degreesS), which marks the equatorward end of the Benguela system, and in the Luderitz region (26-28 degreesS), supporting the suggestion that the Benguela is split into northern and southern parts with limited exchange of near-surface plankton. The cross-isobath movement of drifters at the northern end of the broad Orange River shelf suggests a topographic control on the location and dynamics of the Luderitz filament, in addition to the windstress maximum. Based on mean flow and flow variability exhibited by the drifters, sub-regions are characterized according to whether the transport of surface water is dominated by alongshore advection, offshore advection or 'eddy diffusion'.
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