Study on the atmospheric correction for high spatial resolution bands of MODIS

Application of MODIS in ocean color is mainly based on bands 8-16, whose spatial resolution is 1km. This spatial resolution can't meet the demand of inland waters with small area. Then, taking TaiHu lake in China as an example, we put forward an atmospheric correction algorithm for bands 1 and 2 whose spatial resolution is 250m. Firstly, we choose one pixel whose digital number of band 16 is the smallest in Taihu lake as the clear pixel. The aerosol parameters of the clear pixel are calculated by the standard atmospheric correction algorithm for Case 1 waters. Secondly, we can calculate the aerosol scattering radiance of bands 1, 2 of other pixels with assumption that the aerosol type and optical thickness keep the same over Taihu lake. This algorithm combines the advantage of bands 8-16 in ocean color atmospheric correction with the high spatial resolution of bands 1 and 2. In order to test the precision of this algorithm, we choose an MODIS-Aqua image which are covering Taihu lake and are acquired in the time of 2004 Taihu autumn cruise. We use our atmospheric correction algorithm to process the selected image and compare the retrieved remote sensing reflectance (Rrs) with measured Rrs. The average relative of bands 1 and 2 are respectively 24.85% and 41.44%, demonstrating that this algorithm has the potential of application in the atmospheric correction of inland waters.