Physical-Chemical Oceanography Cruise on the Africana Voyage 077, September 1989

The Physical-Chemical Oceanography Cruise was conducted on the Africana Voyage 077, from 11 - 22 September 1989. There were several objectives to this cruise, covering Physical Environment (PE), Sedimentation and Nutrient cycling (SN), Chemical Environment (CE), Shoal Ecology (SE), Plankton studies (P) and testing of the new AIDA acoustic system with possible estimates of biomass in specific places such as in the baroclinic jets. The cruise objectives included identifying and documenting near-surface and mid-water baroclinic jets west of Cape Columbine and Cape Town using acoustic doppler profiling and Conductivity-Temperature-Depth (CTD) data; observing currents in the upper 200m at regular intervals along the cruise track, using the Acoustic Doppler Current Profiler (ADCP); performing a 30 hour internal tide experiment at the shelf edge west of the Chamais Bay; deploying a series of current meter moorings on the Namibian remote shelf and eastern Cape Basin zones between Chamais Bay and Walvis Bay; servicing a weather station at Pelican Point; recovering a current meter array 90 miles west of Walvis Bay and re-deploying the Kiel sediment trap and current meter array at the same position; deploying the ruggedised Sea Fisheries Research Institute (SFRI) sediment traps in the vicinity of the Orange River and Conception Bay; taking box cores for on-board sediment core incubation at Conception Bay and the same Orange River Mouth site sampled in March 1989; running a set of CTD lines across the shelf to the vicinity of the shelf break; and lastly to draw samples from the labratory seawater sampling probe at regular intervals for fractionation, filtration and calibration of the in-line fluorometer.