Title Processed underway Thermosalinograph (TSG) observations from SA Agulhas II Voyage 024, April 2017
Project Marion Island Relief Voyage
Authors

Leon Jacobs
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE) Marine Scientific Technician 2nd Floor, Foretrust Building, Martin Hammerschlag Way, Cape Town, South Africa, email: LJacobs@environment.gov.za

Marcel van den Berg
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE) Marine Scientific Technician 2nd Floor, Foretrust Building, Martin Hammerschlag Way, Cape Town, South Africa, email: mvdberg@environment.gov.za

Tarron Lamont
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE) Marine Scientist 2nd Floor, Foretrust Building, Martin Hammerschlag Way, Cape Town, South Africa, email: tlamont@environment.gov.za

Publisher Department of Forestry, Fisheries and the Environment (2021)
Contributors

Contact Person: Leon Jacobs
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE) Marine Scientific Technician 2nd Floor, Foretrust Building, Martin Hammerschlag Way, Cape Town, South Africa, email: leon5134@gmail.com

Abstract A SeaBird SBE45 Thermosalinograph (TSG) is used to opportunistically collect underway near-surface temperature and conductivity measurements during research and monitoring cruises. Water is continuously pumped to the TSG from an intake located in the hull of the vessel, and the observations are continuously interfaced with navigational information. A temperature sensor close to the intake provides temperature measurements of the incoming water (T1). The temperature of the water inside the conductivity cell (T2) is used to accurately compute salinity (S) from the conductivity measurements (C). Here we present the 6-second resolution processed TSG data collected between 08 April 2017 and 12 May 2017, during Voyage 024 on the SA Agulhas II.
Methods The SeaBird SBE45 Thermosalinograph (TSG) is used on the SA Agulhas II for the collection of underway near-surface temperature and conductivity measurements. The underway seawater is obtained from a depth of 7m below the surface and pumped through the TSG. Data is collected using the most recent SeaBird (SBE) SeaSave software and processed using the most recent SBE Dataprocessing software. The software was set to record data at 6 second intervals for the duration of the cruise, between 08 April 2017 and 12 May 2017. Data was collected in the southern part of the Benguela Current Large Marine Ecosystem (BCLME) region, on the west and south coasts of South Africa, in the eastern part of the South Atlantic Ocean, and in the Southern Ocean. Unreliable TSG measurements can result from a variety of problems encountered during the cruises, including insufficient water flow, extreme air bubbling during severly adverse weather conditions, debris trapped in the system, or a variety of electronic failures. Detailed visual inspection of the ship trajectory and TSG measurements, as well as comparisons with other concurrent and historical near-surface measurements, and expert knowledge of local conditions, were used to identify and remove all unreliable data.
Data
Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
Temporal extent 08 Apr 2017 – 12 May 2017
Geographic extent

Benguela Current Large Marine Ecosystem (BCLME) region, west and south coasts of South Africa, Southern Ocean

North: -33.0
South: -48.0
West: 18.0
East: 39.0

Vertical extent Max: -7 m
Min: -7 m
Keywords conductivity, INDIAN OCEAN, near-surface, SA Agulhas II, SA Agulhas II 024, salinity, SBE45, temperature, Thermosalinograph, TSG, underway
Related resources
  • This digital object is new version of Raw underway Thermosalinograph (TSG) observations from SA Agulhas II Voyage 024, April 2017 (10.15493/dea.mims.20210416)
  • This digital object is part of Marion Island Annual Relief Voyage on the SA Agulhas II Voyage 024, April 2017 (10.15493/dea.mims.26052207)