Title Processed CTD discrete observations from the Anchovy and Pilchard Spawning Stock Survey on the Africana Voyage 057, November 1987
Authors

Mbulelo Makhetha
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientific Technician; contact details: email: MMakhetha@environment.gov.za

Gavin Tutt
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientific Technician; contact details: email: Gtutt@environment.gov.za

Tarron Lamont
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientist; contact details: email: tlamont@environment.gov.za

Publisher Department of Forestry, Fisheries and the Environment (2023)
Contributors

Contact Person: Mbulelo Makhetha
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientific Technician; contact details: email: mbulelo.makhetha@gmail.com

Contact Person: Gavin Tutt
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientific Technician; contact details: email: gtsglider@gmail.com

Contact Person: Tarron Lamont
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientist; contact details: email: tarron.lamont@gmail.com

Abstract Here we present processed Conductivity-Temperature-Depth (CTD) discrete data from the upcast collected between 05 November and 30 November 1987, during the Anchovy and Pilchard Spawning Stock Survey on the Africana Voyage 057, in the southern part of the Agulhas Current Large Marine Ecosystem (ACLME) on the south coast of South Africa and the southern part of the Benguela Current Large Marine Ecosystem (BCLME) region on the west coast of South Africa. Neil Brown MK3 and MK4 CTD instruments were used to measure pressure, temperature and conductivity through the water column during research and monitoring cruises between 1983 and 2000. The main objective of the cruise was to determine acoustically the biomass of the pilchard and anchovy spawning stocks between Hondeklip Bay and the eastern end of the Agulhas Bank. Additionally, the relationship between the distribution of pelagic fish, their eggs and the water temperature was investigated, and chemical samples were taken along lines of stations as part of an ongoing investigation with the supply of nutrients to the Agulhas Bank.
Methods Neil Brown MK3 and MK4 Conductivity-Temperature-Depth (CTD) instruments were used to measure pressure, temperature and conductivity through the water column during research and monitoring cruises between 1983 and 2000. Temperature was converted from the IPTS-68 scale to the ITS-90 scale, and salinity was computed from conductivity measurements on the 1978 Practical Salinity Scale, according to UNESCO (1991) algorithms. UNESCO (1993) quality control procedures were applied to the data, and obvious erroneous values resulting from problems including electronic spikes, data collection in air, inadequate flow through the conductivity cell, among others, have been removed. Any additional calibrations or corrections have been specified in each data file, where applicable and available.
Data
Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
Temporal extent 15 Nov 1987 – 23 Nov 1987
Geographic extent

Agulhas Current Large Marine Ecosystem (ACLME), Benguela Current Large Marine Ecosystem (BCLME)

North: -34.0
South: -36.5
West: 18.5
East: 23.0

Vertical extent Max: -554.0 m
Min: -0.1 m
Keywords Africana, Africana 057, Conductivity, CTD, Depth, INDIAN OCEAN, Neil Brown CTD, SOUTH ATLANTIC OCEAN, Temperature
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