Dataset: Southern Ocean Silicate

Here we report silicate data (SiOH4) obtained using a programmable Flow Injection (pFI) analyzer connected to the underway seawater system of the RV Investigator during the return transect of the International Nutrient Intercomparison Voyage (INIV). These data were collected in June 2023 at 15-30 min intervals from 52°S, 142°E to 43°S, 147°E in the Australian sector of the Southern Ocean. During this five-day unattended deployment, the pFI instrument operated autonomously for five days, and the resulting surface Si data covered a region spanning from the Polar Frontal Zone (PFZ ~ 52°S) to the vicinity of Hobart Harbor in the Derwent River. The system was calibrated every 24 hours through triplicate runs of a MQ blank and MQ standard (39.7 µmol L-1-Si). Quality control included the analysis of one Kanso RMNS (CR, 14.3 µmol L-1-Si) mid-way through the deployment. These data, obtained using a commercially available pFI analyzer, are used to confirm that pFI is a viable technology for autonomous monitoring of silicate in underway mode.