Estimation of Surface Albedo based on FY-3D MERSI-2 TOA Data

Surface albedo is an important land surface characteristic parameter in the study of radiation an energy balance, which can determine the distribution process of radiant energy between the earth's surface and the atmosphere. In this paper, we propose a direct estimation algorithm based on FY-3D Medium Resolution Spectral Imager -2 (MERSI-2) top of atmosphere reflectivity (TOA). The core of this algorithm is to establish a regression relationship between MERSI-2 TOA and shortwave surface broadband albedo. First, the 6S atmospheric radiation transmission model is used to simulate the TOA of MERIS-2 and MODIS under various atmospheric conditions, multiple observation angles, and various BRDF surface characteristics. Next, a linear regression method is proposed to obtain the conversion coefficient between TOA of MERSI-2 and MODIS. Finally, convert MODIS albedo lookup table into MERSI-2 albedo lookup table. FY-3D MERSI-2 surface albedo can be obtained by calling MERSI-2 lookup table. The cross-validation results show that the proposed algorithm obtains better performance.