[ALFA data - Indonesian Through Flow Region] - Advanced Laser Fluorescence Analyzer (ALFA) data from the Indonesian Through Flow Region from the R/V Roger Ravelle (RR2201) from January to March 2022 (Collaborative Research: Mesoscale variability in nitrogen sources and food-web dynamics supporting larval southern bluefin tuna in the eastern Indian Ocean)

The Automatic Laser Fluorometric Analyzer (ALFA) is a state-of-the-art instrument, that combines high-resolution spectral measurements of blue (405 nm) and green (532 nm) laser-stimulated fluorescence, with spectral deconvolution techniques to estimate CDOM, phytoplankton variable fluorescence (Fv/Fm), Chl a and three types of phycobiliprotein pigments. This data was collected using the ALFA in Underway fluorescence mode and sampling in the western Eastern Indian Ocean Upwelling region on the R/V Roger Ravelle in January - March 2022 (BLOOFINZ).

In underway mode, the ALF is connected to the ship's uncontaminated seawater flow-through system allowing for continuous measurements in water drawn from approximately 5m below the surface. All fluorescence values are Raman-normalized, with the exception of Chl a, which was calibrated with acetone extracted samples measured in a Turner Designs® Trilogy Fluorometer. The instrument is set up to make these measurements approx. every minute.