Surface Albedo Inversion of FY-3C MERSI Data

Abstract

The surface albedo indicates the ability of the Earth's surface to reflect solar radiation, and it is an important land surface characteristic parameter that affects the radiation and energy balance of the Earth system. This paper presents a surface albedo inversion method for FY-3C MERSI. First, we estimated the narrow-band surface albedo for different surface cover types by using constrained least squares and the RossThick-LiTransit model. Then, we calculated the conversion coefficient of the FY-3C MERSI narrow-band surface albedo to the broad-band surface albedo conversion by using the FY-3C MERSI spectral response function, the 6S radiation transmission model and the USGS spectral library. Finally, we obtained the surface black and white albedo of the four narrow-band and visible-light bands of the FY-3C MERSI, and the spatial resolution of the data is 250m. In the comparative verification experiment, we cross-validated the surface albedo of FY-3C with the surface albedo of MODIS (moderate-resolution imaging spectroradiometer), CGLS (Copernicus Global Land Service) and GLASS (Global LAnd Surface Satellite). The results show that the correlation coefficient is mostly above 0.75, the overall absolute deviation is 0.068 on average and the minimum root mean square error is 0.02 between the albedo products obtained in this paper and the above three products. Therefore, FY-3C MERSI surface albedo products and MODIS, CGLS, GLASS surface albedo products have good consistency in four narrowband and visible light bands.