Assessment of the Consistency and Stability of CrIS Infrared Observations Using COSMIC-2 Radio Occultation Data over Ocean

The accuracy of brightness temperature (BT) from the Cross-track Infrared Sounder (CrIS) onboard Suomi National Polar-orbiting Partnership (S-NPP) satellite and NOAA-20 is estimated using Constellation Observing System for Meteorology, Ionosphere, Climate 2 (COSMIC-2) radio occultation (RO) wet retrievals (temperature water vapor profiles) as input to Community Radiative Transfer Model (CRTM). matchup criteria between RO CrIS observations are time less than 30 min, a distance 50 km, over oceans reduce collocation simulation uncertainty. Based on information provided in observations, only upper sounding channels with weighting function peak height (WFPH) above 200 hPa (~12 km) longwave infrared (LWIR) shortwave (SWIR) bands mid-wave (MWIR) band WFPH 500 (~6.3 selected comparison minimize impacts surface emission, cloud absorption/scattering, atmospheric gaseous absorption. absolute differences their CRTM simulations data 1.0 K majority those channels. double S-NPP transfer references very stable. They range −0.05 0.15 LWIR −0.20 0.10 SWIR during two years 1 October 2019 September 2021. For MWIR channels, −0.15 0.25 but have significant variations both daily mean monthly series. results provide ways understand qualities retrieval measurements: can be used assess consistency stability quantitatively, measurements quality retrievals.