Fig. 1. The location of Dome C in the south hemisphere

Fig. 2. TOA lunar spectral irradiance from MT2009 under five different LPAs in 2019

Fig. 3. The flow chart of the evaluation of performance and consistency of on-orbit radiometric calibration of VIIRS DNB on SNPP and NOAA-20

Fig. 4. [in Chinese]

Fig. 5. The simulated and observed radiance of SNPP VIIRS DNB versus LPA, second order polynomial fitting curve between the simulated radiance and LPA, fitting equation, correlation coefficient, and residual during each lunar cycle of 2018-2020

Fig. 6. The simulated and observed radiance of NOAA-20 VIIRS DNB versus LPA, second order polynomial fitting curve between the simulated radiance and LPA, fitting equation, correlation coefficient, and residual during each lunar cycle of 2018-2020

Fig. 7. The absolute value of the difference between the simulated and observed radiance of SNPP VIIRS DNB versus DOY in 2018, 2019, 2020 are in the top half of a1, b1 and c1; the LPA of SNPP VIIRS DNB versus DOY in 2018, 2019, 2020 are in the bottom half of a1, b1 and c1; the absolute value of the difference between the simulated and observed radiance of NOAA-20 VIIRS DNB versus DOY in 2018, 2019, 2020 are in the top half of a2, b2 and c2; the LPA of NOAA-20 VIIRS DNB versus DOY in 2018, 2019, 2020 are in the bottom half of a2, b2 and c2.

Fig. 8. The distance corrected radiance of VIIRS DNB on SNPP and NOAA-20 versus LPA during each lunar cycle of 2018-2020

Fig. 9. The ratio of the calculated radiance between NOAA-20 and SNPP VIIRS DNB versus LPA during each lunar cycle of 2018(a), 2019(b) and 2020(c)

Table 1. The range of specific DOY and date in every lunar cycle during 2018-2020