Inversion Of Ocean Color Constituents In The Sea Area Around Dajin Island Based On Casi Aerial Hyperspectral Data

The sea area of Dajin Island in the Pearl River Estuary is the habitat of the Chinese White Dolphin. The CASI(Compact Airborne Spectrographic Imager) hyperspectral data was used to observe the three constituents of ocean color (chlorophyll-a, suspended sediment concentration and chromophoric dissolved organic matter), which play an important role in reflecting water quality, indicating sea environment and water eutrophication, and the inversion model of three constituents of ocean color is constructed. In addition, the in situ measured water color constituent data is used to evaluate the accuracy of the inversion results. The results show that: 1) the band ratio model (Chla=0.9601x(Rrs(622.486)/Rrs(851.341))+0.0739) based on CASI data can well retrieve the chlorophyll-a (Chl-a) concentration in the studied sea area, the content is 0.1-4.4 mu g / L, and the relative average error is 14.77%.2) The single-band index model (SSC=0.4829xexp(19.619xRrs(622.486)))based on CASI data can better invert the concentration of suspended sediment concentration (SSC), the concentration is 0.48-12.15 mg/L, and the relative average error is 11.16%3) The band ratio model(CDOM=1.0222e<^> (-2.144x (Rrs(B36)/Rrs(B3))) based on CASI data can better invert the concentration of chromophoric dissolved organic matter (CDOM) in the studied sea area, with a relative average error of 12.80%. This shows that CASI airborne remote sensing has a very important role in developing refined observations for specific areas, and can more quickly and effectively monitor the ecological environment and evaluate pollution in the cloudy coverage study area.