Atmospheric correction of the CASI hyperspectral image using the scattering angle by the direct solar beam

In the atmospheric correction of the CASI hyperspectral image, we found that the biggest factor is the downward scattering of the direct solar beam in the exact direction to be reflected at the water surface to be detected by the sensor. The downward scattering angle was calculated using navigation data, viewing geometry, and solar ephemeris. One benefit of this approach is that it is now possible to avoid the limitations posed by the dark-pixel method. Since the scattering angle is computed using geometry only, it is completely free from the possible trouble met by the dark-pixel approach. In this paper, we illustrate the computational procedure and show examples of marine remote sensing data.