Title Processed CTD continuous observations from the South West African Pilchard and Anchovy Biomass Survey on the Africana Voyage 074, June 1989
Authors

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

Abstract Here we present processed downcast Conductivity-Temperature-Depth (CTD) continuous data collected, between 22 June and 04 July 1989, during Voyage 074 on the FRS Africana, in the Benguela Current Large Marine Ecosystem (BCLME) region on the west coast of Southern 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 South West African Pilchard and Anchovy Biomass Survey were to undertake an acoustic / trawling survey of the pilchard stock off SWA and arrive at a stock estimate; to survey the horse-mackerel and anchovy stocks off South West Africa (SWA) and obtain stock estimates if possible and to collect the environmental information on the habitat of the above species primarily by means of CTD and U³ dips in the upper 200m.
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 23 Jun 1989 – 29 Jun 1989
Geographic extent

Benguela Current Large Marine Ecosystem (BCLME)

North: -17.5
South: -24.5
West: 11.5
East: 14.5

Vertical extent Max: -112 m
Min: -1 m
Keywords Africana, Africana 074, Conductivity, CTD, Depth, Neil Brown CTD, SOUTH ATLANTIC OCEAN, Temperature
Related resources
  • This digital object is described by https://unesdoc.unesco.org/ark:/48223/pf0000090489
  • This digital object is described by https://unesdoc.unesco.org/ark:/48223/pf0000138825
  • This digital object is new version of Raw CTD continuous observations from the South West African Pilchard and Anchovy Biomass Survey on the Africana Voyage 074, June 1989 (10.15493/DEA.MIMS.11672023)
  • This digital object is part of South West African Pilchard and Anchovy Biomass Survey on the Africana Voyage 074, June 1989 (10.15493/DEA.MIMS.11852023)