Continuous pCO2 and Sea-Air CO2 Net Fluxes from the Following Ocean Rings in the South Atlantic (FORSA) cruise

• Main Authors: Orselli, Iole Beatriz Marques, Kerr, Rodrigo, Azevedo, José Luiz Lima de, Galdino, Felippe, Araujo, Moacyr, Garcia, Carlos Alberto Eiras
• Format: Dataset
• Language: English
• Published: PANGAEA 2023
• Subjects: Agulhas rings; Air-sea CO2 flux; Calculated; Carbon dioxide; sea-air; flux; CT; DATE/TIME; Day of the year; DEPTH; water; eddies; FORSA; FORSA-track; LATITUDE; LONGITUDE; Partial pressure of carbon dioxide (ambient atmosphere); Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); temperature-normalized; pCO2; Salinity; Temperature; Underway cruise track measurements; Vital de Oliveira; Δ partial pressure of carbon dioxide; Forsa; Ocean acidification; South Atlantic Ocean
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.957502; https://doi.org/10.1594/PANGAEA.957502

Here we provide CO2-system properties that were continuously measured in a southeast-northwest transect in the South Atlantic Ocean in which six Agulhas eddies were sampled. The Following Ocean Rings in the South Atlantic (FORSA) cruise occurred between 27th June and 15th July 2015, from Cape Town – South Africa to Arraial do Cabo – Brazil, on board the first research cruise of the Brazilian Navy RV Vital de Oliveira, as part of an effort of the Brazilian High Latitude Oceanography Group (GOAL). Finally, it contributed to the activities developed by the following Brazilian networks: GOAL, Brazilian Ocean Acidification Network (BrOA), Brazilian Research Network on Global Climate Change (Rede CLIMA). The focus of the first study using this dataset (Orselli et al. 2019a) was on investigate the role played by the Agulhas eddies on the sea-air CO2 net flux along their trajectories through the South Atlantic Ocean and model the seawater CO2–related properties as function of environmental parameters. This data has been used to contribute to the scientific discussion about the Agulhas eddies impact on the changes of the marine carbonate system, which is an expanding oceanographic subject (Carvalho et al. 2019; Orselli et al. 2019b; Ford et al. 2023). Seawater and atmospheric CO2 molar fraction (xCO2sw and xCO2atm, respectively) were continuously measured during the cruise track, as well as the sea surface temperature (T) and salinity (S). The following sampling methodology is fully described in Orselli et al. (2019a). The underway xCO2 sampling was taken using an autonomous system GO–8050, General Oceanic®, equipped with a non-dispersive infrared gas analyzer (LI–7000, LI–COR®). The underway T and S were sampled using a Sea-Bird® Thermosalinograph SBE21. Seawater intake to feed the continuous systems of the GO-8050 and the SBE21 was set at ~5 m below the sea surface. The xCO2 system was calibrated with four standard gases (CO2 concentrations of 0, 202.10, 403.20, and 595.50 uatm) within a 12 h interval along the entire ...