SNPP VIIRS thermal emissive band performance after three years on-orbit

Abstract

The Suomi National Polar-orbiting Partnership (SNPP) spacecraft's primary sensor is the Visible-Infrared Imaging Radiometer Suite (VIIRS) which launched on October 28, 2011. It has 22 total bands with 7 thermal emissive bands (TEBs), a high dynamic range monochromatic Day Night Band (DNB) and 14 reflective solar bands (RSBs). The TEB gain and noise performance is tracked on-orbit using an On-Board Calibrator BlackBody (OBCBB) as a thermal source. The TEBs view the OBCBB every scan allowing gain correction roughly every 1.7 seconds. Long term trending of the F factor (inversely proportional to gain) and Noise Equivalent delta Temperature (NEdT) allows the stability and uncertainty in the TEB thermal model to be evaluated. This paper will discuss the impacts of the thermal model uncertainties on the VIIRS calibration and how those impact the long term performance of VIIRS. It will also show the stability of the TEBs over 3 years on-orbit.