A Four-Step Method for Estimating Suspended Particle Size Based on In Situ Comprehensive Observations in the Pearl River Estuary in China

The suspended particle size has great impacts on marine biology environments and biogeochemical processes, such as the settling rates of particles sunlight transmission in water. However, spatial–temporal variations sizes coastal waters are rarely reported due to paucity appropriate observations limitations retrieval methods, especially areas with complex optical properties. This study proposed a remote sensing-based method for estimating median Dv50 (calculated range 2.05–297 μm) that correlates inherent properties (IOPs) retrieved from situ sensing reflectance above water’s surface (Rrs(λ)) Pearl River estuary (PRE) China. Rrs(λ) was resampled simulate Multispectral Instrument (MSI) onboard Sentinel-2A/B, wavebands 490, 560, 705 nm were utilized IOPs. results this had statistical performance 0.86, 18.52, 21.28%, −1.85 R2, RMSE, MAPE, bias values, respectively, validation, which indicated could be estimated by four-step method. Then, applied Sentinel-2 MSI imagery, clear difference distribution different time seen. holds potential monitoring waters.