Dissolved inorganic carbon (DIC), total alkalinity, water temperature, salinity and other variables collected from discrete sample and profile observations during R/V Marion Dufresne OISO-21 cruise (EXPOCODE 35MF20120125) in the South Indian Ocean and the corresponding Southern Ocean sector from 2012-01-25 to 2012-03-07 (NCEI Accession 0290760)

This dataset is part of the long-term monitoring program OISO (Ocean Indien Service d'Observations) initiated in 1998, and covering contrasting regions in the South-West Indian Ocean from the subtropics to the Antarctic zone. It includes hydrological and biogeochemical measurements (temperature, salinity, oxygen, total CO2, alkalinity, nutrients, chlorophyll-a, d13C and d18O) collected in the water column (17 stations) using a rosette-CTD equipped with 24 Niskin bottles. Most of the samples were collected from the surface down to 1200m, except for 2 deep stations (down to the bottom at 30°S and 56.5°S). During the OISO-21 cruise we also collected underway fCO2 data (NCEI Accession 0116411), as well as underway total CO2 and alkalinity data (NCEI Accession 0177325) and complementary parameters collected in surface waters every 4h to 8h (nutrients, chlorophyll-a, d13C and d18O). The OISO data are regularly included in international data syntheses (SOCAT, GLODAP).