Assessing net growth of phytoplankton biomass on hourly and daily timescales using the GOCI geostationary ocean color sensor.

Bror F Jonsson, University of New Hampshire Main Campus, Durham, NH, United States, Joseph Salisbury II, University of New Hampshire, Durham, NH, United States, Wonkook Kim, (Currently) Pusan National University, Department of Civil and Environmental Engineering, Busan, South Korea and Antonio Mannino, NASA Goddard Space Flight Center, Ocean Ecology Laboratory, Greenbelt, MD, United States
For over three decades, assessments of global oceanic biological production at seasonal to annual time scales have been made using satellite-derived properties. A remaining challenge, however, centers on the temporal resolution needed to detect actual changes in carbon fixation over shorter time intervals. We present novel satellite-derived proxies of net primary and community production based on the Geostationary Ocean Color Imager (GOCI) that provide direct growth and loss estimates of the phytoplankton community. Hourly data pooled from the optically clear waters in the Yellow Sea (YS), East China Sea (ECS) and East/Japan Sea (EJS) for the year 2016, are used to evaluate the growth and loss of phytoplankton biomass over diurnal to annual time scales. Analyses of hourly data over the illuminated day reveals net chlorophyll growth patterns that vary spatially and temporally at both diurnal and seasonal timescales. Since high frequency data are essential for an improved understanding of diurnal growth patterns over large spatial regions, geostationary ocean color data offer an unprecedented potential to provide accurate constraints on primary productivity.