Abstract
After extensive calibration/validation efforts, the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard Suomi NPP has reached cal/val maturity which is a major milestone in an effort to produce high quality weather and climate related satellite data products. Multiple independent cal/val studies since launch have suggested that the VIIRS absolute radiometric accuracy for most of the RSB bands is within 2%. VIIRS is a follow on mission for MODIS and AVHRR. It is very important to perform cross-comparison between VIIRS and NOAA AVHRR to establish data continuity for multi-decadal Earth observation from AVHRR with VIIRS for global climate change studies. The study uses two major approaches, one is using simultaneous nadir overpass (SNO) approach over higher latitudes and the other is extension of SNO to low latitudes (SNO-x). The radiometric consistency is quantified using both approaches. The impact due to spectral differences of the matching bands of the two instruments is analyzed using hyperspectral measurements and radiative transfer model (MODTRAN). The radiometric bias estimated is further validated at highly stable vicarious calibration sites such as Dome C.
Assessing the Radiometric Consistency between S-NPP VIIRS and NOAA-19 AVHRR for Data Continuity
After extensive calibration/validation efforts, the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard Suomi NPP has reached cal/val maturity which is a major milestone in an effort to produce high quality weather and climate related satellite data products. Multiple independent cal/val studies since launch have suggested that the VIIRS absolute radiometric accuracy for most of the RSB bands is within 2%. VIIRS is a follow on mission for MODIS and AVHRR. It is very important to perform cross-comparison between VIIRS and NOAA AVHRR to establish data continuity for multi-decadal Earth observation from AVHRR with VIIRS for global climate change studies. The study uses two major approaches, one is using simultaneous nadir overpass (SNO) approach over higher latitudes and the other is extension of SNO to low latitudes (SNO-x). The radiometric consistency is quantified using both approaches. The impact due to spectral differences of the matching bands of the two instruments is analyzed using hyperspectral measurements and radiative transfer model (MODTRAN). The radiometric bias estimated is further validated at highly stable vicarious calibration sites such as Dome C.