On-Orbit Infrared Radiometric Calibration and Land Surface Temperature Inversion of FY-3C MERSI

In this paper, the spectral characteristics, performance of spaceborne radiation source, in orbit infrared radiometric calibration method and radiance data generation process of the Medium Resolution Spectral Imager (MERSI) of FY-3C satellite are introduced. The land surface temperature of typical areas is inversed using the radiometric calibration data. The nonlinear radiometric calibration method for the long wavelength infrared channel with wide spectrum is discussed, the cold space and on-board radiometer count values are obtained independently in each scanning cycle of the instrument, and the infrared channel in orbit calibration calculation is carried out. According to the infrared radiation calibration results, the single channel method is used to retrieve the land surface temperature. The calibration and inversion results provide an important basis for FY-3C/MERSI in orbit performance evaluation.