| Title | Processed CTD discrete observations from the West Coast Hake Biomass Survey on the Africana Voyage 054, June 1987 |
|---|---|
| Project | West Coast Hake Biomass |
| Authors |
Makhetha, Mbulelo Tutt, Gavin Lamont, Tarron |
| Publisher | Department of Forestry, Fisheries and the Environment (2023) |
| Contributors |
Contact Person: Tutt, Gavin |
| Abstract | Here we present processed Conductivity-Temperature-Depth (CTD) discrete data from the upcast collected between 16 June and 10 July 1987, during the West Coast Hake Biomass Cruise on the Africana Voyage 054, in 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 scientific targets of the trip revolved around the determination of biomass index of both Cape hake species off the South African west coast. The diurnal cycle of Cape hake and their relationship with environmental parameters was also studied. Some hake material were collected in South West African waters. Deep-water trawls were made to delimit the offshore extent of hake distribution and to collect rare specimens of fish for accession to museums. Demersal community interrelationships were studied, as were spatial distribution patterns and spawning fractions of round herring. |
| 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 | |
| Temporal extent | 16 Jun 1987 – 10 Jul 1987 |
| Geographic extent |
Benguela Current Large Marine Ecosystem (BLMCE)
North: -29.0 |
| Vertical extent |
Max: -471.2 m Min: 0.0 m |
| Keywords | Africana , Africana 054 , Conductivity , CTD , Depth , EOV: Physics > Subsurface salinity , EOV: Physics > Subsurface temperature , Neil Brown CTD , SOUTH ATLANTIC OCEAN , Temperature |
| Related resources |
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