SmallSat for Monitoring Aquatic Ecosystem of Coastal and Inland Waters: The Experience of HiSea-II

HiSea-II, designed for monitoring coastal-inland biogeochemical properties and launched into orbit on June 11, 2021, is the first small satellite (SmallSat) simultaneously satisfying high spatial resolution (20 m), high signal-to-noise ratio (SNR) (~300) and wide swath (~200 km). In this article, we provide detailed descriptions of this SmallSat, introduce its data products, highlight its unique features, also share its shortcomings so future such SmallSat could be improved. SmallSat for ocean color is at its early stage, we advocate more investment and efforts to advance this useful platform, so a constellation of ocean-color SmallSats could be established in the future for effective monitoring of coastal-inland aquatic ecosystems.