VIIRS TEB calibration uncertainty analysis

The VIIRS sensor has 7 Thermal Emissive Bands (TEB) - spectra cover from 3.7 through 12.0 mu m - that are calibrated on-orbit using observations from its on-board blackbody. As part of the prelaunch calibration activities, the on-orbit retrieved radiance total calibration uncertainty of the TEB was estimated for both VIIRS (onboard the S- NPP and NOAA-20 spacecraft) instruments currently in orbit. However, no uncertainty algorithm was developed nor implemented in the Level 1B (L1B) product for the NASA Science Investigator-led Processing Systems (SIPS). This study presents the methodology, analysis, and uncertainty look-up tables used to develop a calibration uncertainty algorithm for the VIIRS TEB that is currently being implemented in the NASA SIPS L1B product. The on-orbit retrieved total uncertainties for each TEB were compared to specified uncertainty limits at a series of scene temperatures. Results indicate that the estimated uncertainties were compliant with their respective specifications, except for bands M12 and M13 at lower scene temperatures. For the midwave infrared bands, the on-orbit detector response and response-versus-scan-angle are the most dominant uncertainty contributors over cold scenes, while the blackbody radiance terms drive the uncertainty on the warmer temperature end. The longwave infrared bands uncertainties are mostly determined by on-orbit detector response and response-versus-scan-angle over all scene temperatures. It was also found that the longwave infrared TEB uncertainties showed some scan angle dependence at the lower scene temperatures. The methods presented here can be used to develop similar L1B uncertainty algorithms for the TEB in the VIIRS sensors that will be onboard future Joint Polar Satellite System missions.