NOAA-20 VIIRS ON-ORBIT CALIBRATION AND PERFORMANCE UPDATE

Launched in November 2017, the NOAA-20 (N-20) VIIRS has successfully completed more than 1.5 years of on-orbit operations. In addition to initial post-launch check-outs followed by a series of intensive calibration and validation activities, the instrument performed a mid-mission outgassing in March 2018 to remove the ice buildup on the dewar window of the long-wave infrared (LWIR) focal plane assembly that had caused gradual degradation of detector responses (gains) of several LWIR spectral bands. Since then, the instrument has been in nominal operations. This paper provides an update of N-20 VIIRS on-orbit calibration activities and performance assessments using data from its on-board calibrators (OBCs) and regularly scheduled lunar observations, and discusses issues identified and efforts made to improve the calibration and data quality. Also briefly described in this paper are remaining challenges in terms of calibration consistency between NOAA-20 and S-NPP VIIRS.