| Title | Processed CTD discrete observations from the South Coast Hake Biomass Survey on the Africana Voyage 056, September 1987 |
|---|---|
| Authors |
Mbulelo Makhetha Gavin Tutt Tarron Lamont |
| Publisher | Department of Forestry, Fisheries and the Environment (2023) |
| Contributors |
Contact Person: Mbulelo Makhetha Contact Person: Gavin Tutt Contact Person: Tarron Lamont |
| Abstract | Here we present processed Conductivity-Temperature-Depth (CTD) discrete data from the upcast collected between 08 September and 05 October 1987, during the South Coast Hake Biomass Cruise on the Africana Voyage 056, 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 objectives of the cruise were to survey by means of trawling the abundance of adult and recruiting hake, sole and other trawl target species; to investigate the environment and ecological interrelationships of hake and other demersal species in the various depth strata; to investigate the occurence, distribution and abundance of squid and squid larvae; to investigate the occurence of linefish species in shallow waters; to identify every species caught in the trawl net; and to do chondrichthyian research. Oceanographic research assistants were also trained. |
| 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 | 09 Sep 1987 – 04 Oct 1987 |
| Geographic extent |
Agulhas Current Large Marine Ecosystem (ACLME), Benguela Current Large Marine Ecosystem (BCLME)
North: -33.5 |
| Vertical extent |
Max: -513.0 m Min: -0.01 m |
| Keywords | Africana, Africana 056, Conductivity, CTD, Depth, INDIAN OCEAN, Neil Brown CTD, SOUTH ATLANTIC OCEAN, Temperature |
| Related resources |
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