| Popis: |
The Hyperion sensor is the first high spatial resolution imaging spectrometer to successfully orbit the earth, which was designed for demonstration purpose on new technology for the Earth Observing Mission. The paper mainly focuses on the environmental applications in water quality monitoring with the combination of inherent optical properties and Hyperspectral data. The Hyperion data was atmospherically corrected with the MODTRAN-4 procedure using a Gaussian spectral response function. The in situ measurements was taken nearly at the same time that Hyperion overpasses, retrieving the concentrations of chlorophyll a (chl-a), suspended sediment (ss), the absorption coefficients in 440nm of yellow substance and the inherent optical properties (absorption coefficients and backscattering coefficients). The specific coefficients of absorption and scattering of the three optical active substances (chlorophyll a, suspended matter and yellow substance) from 400 to 750nm in 1 nm increment were measured and analyzed in the laboratory. The analytical reflectance model and matrix inversion method that can account for the mutual influence of the water constituents, are employed to map the spatial distribution of chlorophyll a, suspended sediments and the absorption coefficients in 440nm of yellow substance, which are comparable to those estimated by the statistical model and the field truth. Therefore, a better estimate of the specific inherent optical properties and necessary atmospheric correction, the Hyperion data can be used to map the concentrations of the optical active substances simultaneously in the complex inland waters, which will underlie the project of water quality monitoring using multi-temporal remote sensing data. |
