Improvements in the identification of CTIA saturation in NASA VIIRS L1B

The two VIIRS instruments onboard the Suomi NPP and NOAA-20 spacecraft collect data in 22 spectral bands from 0.4 mu m to 12.5 mu m. Both instruments have exhibited a known artifact in the behavior of the capacitive transimpedance amplifier (CTIA) that manifests in a double-valued (rollover) response in the Earth view imagery. This behavior was identified and well characterized prelaunch and is predominant for the single-gain band M6. The rollover phenomenon is also observed in the low-gain stages of the dual-gain reflective solar bands and thermal bands M12 and I4. The NASA VIIRS L1B processing currently has a rollover flagging scheme that is based on fixed thresholds in the digital numbers (DN) that approximately correspond to the designed maximum radiance of the band. In this work, we briefly review the prelaunch results, current on-orbit flagging methodology, and propose improvements for future implementation in the NASA Level 1B products. Results indicate significant improvement via more accurate flagging for the rollover pixels in band M6 as well as other RSB. The methodologies developed in this work could also be applicable to future VIIRS instruments to be launched aboard the JPSS-2-4 spacecrafts.