Raw underway Thermosalinograph (TSG) observations from the Integrated Ecosystem Programme: Southern Benguela (IEP:SB) on the Algoa Voyage 258, February 2019

Here we present the 6-second resolution raw Thermosalinograph (TSG) data between 28 February 2019 and 07 March 2019 during the Integrated Ecosystem Programme: Southern Benguela (IEP:SB) on the RS Algoa Voyage 258. A SeaBird SBE45 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). This is a long-term monitoring line conducted off the coast of Kleinsee, Namaqualand, Elands/St Helena Bay and Scarborough on the west coast of South Africa. 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.