Abstract: Marine phytoplankton contribute roughly half the net primary production (NPP) on Earth, fixing atmospheric CO2 into food that fuels global ocean ecosystems and drives biogeochemical cycles (e.g., Field et al. 1998; Falkowski et al. 1998). Satellite ocean color sensors, such as SeaWiFS (McClain 2009), MODIS (Esaias et al. 1998), and VIIRS (Oudrari et al. 2015), provide observations of sufficient frequency and geographic coverage to globally monitor changes in the near-surface concentrations of…