Geolocation Assessment and Optimization for OMPS Nadir Mapper: Methodology

Onboard both the Suomi National Polar-orbiting Partnership and Joint Polar Satellite System (JPSS) series of satellites, Ozone Mapping Profiler Suite Nadir Mapper (OMPS-NM) is a new generation total ozone column sensor used to generate products. This study presents method for efficiently assessing OMPS-NM geolocation accuracy using spatially collocated radiance measurements from Visible Infrared Imaging Radiometer (VIIRS) Moderate Band M1 by taking advantage its high spatial resolution (750 m at nadir) accurate geolocation. The basic idea find best collocation position with maximum correlation between VIIRS real radiances perturbing line-of-sight (LOS) vectors in cross-track along-track directions small steps spacecraft coordinate. perturbation angles where are optimally aligned characterize accuracy. In addition, assessment results can be optimize field view angle lookup table Sensor Data Record (SDR) processing software improve To demonstrate methodology, proposed successfully employed evaluate different resolutions. indicate that, after was updated, SNPP NOAA-20 on sub-pixel level (less than ¼ pixel size) along all scan positions performance very stable time. this lays down framework future high-resolution measurements.