Dataset: Phosphate Time Series Data Obtained from an Autonomous Programmable Flow Injection (pFI) Analyzer at CeNVOOS Moss Landing Shore Station during February 2022 (pFI-SI-LOV project)

We deployed a pFI analyzer at the Central and Northern California Ocean Observing System (CeNCOOS) Moss Landing shore station in February 2022. The instrument was equipped with an auxiliary diaphragm pump and sample loop for hourly phosphate analysis of samples withdrawn from the station’s seawater intake line. The samples were then analyzed using a pFI analyzer running on the assay described in Murphy and Riley (1962), adapted for pFI use. During this 6-day deployment, we configured the pFI analyzer to create a four-point calibration curve (0, 0.5, 1.5 and 3.0 µmol L-1 PO4) every 12 hours using a single MQ phosphate standard (3.0 µmol L-1 PO4). In the intervals between these calibrations, the pFI was programmed to withdraw and analyze a sample from the seawater intake line hourly. The calibration procedure involved aspirating a fixed volume of the concentrated standard into one of the holding coils and simultaneously dispensing a variable volume of diluent (MQ carrier) to set the appropriate dilution factor.