Fig. 1. Spatial distribution of radiosondes after matching （the red sites are participating in the evaluation，and blue sites are not used；the right side is the relative time of FY-4A/GIIRS scanning sequence）

Fig. 2. The schematic diagram of FY-4A/GIIRS pixel matching with radiosonde data （The red point is radiosonde site of Beijing 54511，the black dots are FY-4A/GIIRS pixels，and the shaded is the coverage area around the radiosonde site with a radius of 92 km）

Fig. 3. Effectiveness of FY-4A/GIIRS atmospheric temperature profile（a）UTC 00：00（b）UTC 12：00

Fig. 4. Accuracy evaluation of FY-4A GIIRS temperature profile retrieval (a）Bias and RMS（b）relative error and annually average temperature profile; in the legends, clear, cloud and all represent clear sky, cloudy and all cases statistical results respectively, and the suffix c represents the first Cressman matching method, and n represents the second nearest pixel matching method)

Fig. 5. Temperature scatterplot of FY-4A/GIIRS inversion and radiosonde data at Beijing site 54511（clear and cloud represent clear sky and cloudy respectively，and R is the correlation coefficient of the clear sky）

Fig. 6. Accuracy evaluation of clear sky temperature profile for FY-4A GIIRS inversion (a）Bias and RMS（b）relative error and sample number; 00 and 12 in the legends mean UTC observation time which represent day time and night respectively)

Fig. 7. Monthly quality analysis of FY-4A GIIRS temperature profile (a)Bias(b) RMS(c) MRE(d) Correlation coefficient

Fig. 8. Monthly statistics of cloud coverage of matching samples (a) UTC 00:00(b) UTC 12:00

Fig. 9. Spatial distribution of RMS for FY-4A GIIRS temperature profiles with reference to radiosonde (a) Average RMS of the entire layer(b) RMS of the lowest layer

Fig. 10. RMS and standard deviation with reference to radiosonde at different altitudes (a) RMS(b)standard deviation; L, M, H and all in the legend represent the statistical results of low altitude, medium altitude, high altitude and all cases respectively

Fig. 11. Bias probability density of temperature profiles of FY-4A/GIIRS （the abscissa represents the proportion of RMS in corresponding height level）