| Title | Processed underway Thermosalinograph (TSG) observations from the Integrated Ecosystem Programme: Southern Benguela (IEP:SB) cruise on the Algoa Voyage 272, May 2021 |
|---|---|
| Project | Integrated Ecosystem Programme: Southern Benguela (IEP: SB) |
| Authors |
Leon Jacobs Marcel van den Berg Tarron Lamont |
| Publisher | Department of Forestry, Fisheries and the Environment (2023) |
| Contributors |
Contact Person: Leon Jacobs Contact Person: Marcel van den Berg Contact Person: Tarron Lamont |
| Abstract | Here we present the 6-second resolution processed Thermosalinograph (TSG) data collected between 14 May and 21 May 2021 during the Integrated Ecosystem Programme: Southern Benguela (IEP:SB) cruise on the Algoa Voyage 272. 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). The IEP:SB in 2013 consolidated a long-term, multi-decadal time-series (from 1951 onward) of information for this important region and has continued monitoring in the form of the IEP:SB. The programme is a multi-disciplinary, collaborative and capacity building platform undertaking relevant science, including updating technology, with the aim to develop ecosystem indicators that can be used to effectively monitor and understand the Southern Benguela. These include physical, chemical, planktonic, microbial, seabird, marine mammal, benthic and pollution (plastic) ecosystem indicators as required by ecosystem-based management regarding the following priorities: ocean warming, ocean acidification, trophic functioning, pollution and water quality. It is on-going monitoring programme. |
| Methods | The SeaBird SBE45 Thermosalinograph (TSG) is used on the Algoa for the collection of underway near-surface temperature and conductivity measurements. The underway seawater is obtained from a depth of 5m 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 data processing software. The software was set to record data at 6 second intervals for the duration of the cruise, between 14 May 2021 and 21 May 2021. Data was collected in the southern part of the Benguela Current Large Marine Ecosystem (BCLME) region on the west coast of South Africa. Unreliable TSG measurements can result from a variety of problems encountered during the cruises, including insufficient water flow, extreme air bubbling during severely 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 | |
| Temporal extent | 14 May 2021 – 21 May 2021 |
| Geographic extent |
Benguela Current Large Marine Ecosystem (BLMCE); shelf region on the west coast of South Africa
North: -29.0 |
| Vertical extent |
Max: -5.0 m Min: -5.0 m |
| Keywords | Algoa, Algoa 272, SOUTH ATLANTIC OCEAN, THERMOSALINOGRAPH, TSG |
| Related resources |
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