Cross-calibration of FY-1C/1D satellite based on hyper-spectral data

Cross-calibration aims to inter-calibrate a diverse range of satellite instruments to produce corrections ensuring their data consistency, allowing them to be used to produce globally homogeneous products for environmental monitoring. To ensure the maximum consistency and traceability of FY-1C/FY-1D satellite data, it is desirable to perform the inter calibration using the AIRS (Atmospheric Infrared Sounder，AIRS) data and the algorithms based on the principles: Observations are collocated, and pixels are matched with the spectral, spatial and temporal as well as viewing geometry matching included，and then compared and analysed to produce calibration correction functions, transforming the observations to common references. Inter-calibration results indicate that observations of channel 4 and 5 of FY-1C are 1.3 K lower and 3.6 K lower than those of AIRS, respectively, and for FY-1D there are 0.3 K and 3.6 K lower, respectively. Re calibration which aims to produce revised sets of calibration coefficients for FY-1C/1D following its inter calibration against the reference instrument was also done. These would make data from FY-1C/1D to be consistent with the reference instrument.