SNPP CrIS Sensor Data Record: Validated Maturity Level Product

The Cross-track Infrared Sounder (CrIS) flying on the Suomi National Polar-orbiting Partnership Satellite (SNPP) is a Fourier transform spectrometer, the first in a series of next generation weather satellites as part of the Joint Polar Satellite System (JPSS). It provides Infrared radiance measurements with 1305 channels and the data will be used for numerical weather predictions, climate trending and retrievals of trace gases, land surface properties and cloud properties. Since the power up of the CrIS instrument on January 18th, 2012, the CrIS Sensor Data Record (SDR) team has been working on post-launch instrument optimization and the SDR calibration and validation (CalVal). The CrIS SDR product is provided to the public at three stages of maturity level: the Beta, Provisional and Validated. The product has reached the Beta and Provisional maturity levels, and is expected to reach the Validated level in January 2014. CrIS has been providing low noise high-quality measurements since the beginning of the mission. All the radiometric and spectral performance specifications have been significantly exceeded. The overall radiance noise levels of the three bands are well below the specifications, by 30% to 90%. The overall spectral uncertainty is about 2 ppm, better than the specification of 10 ppm. The 3-sigma overall radiometric uncertainties of the three bands are below 0.3 K, better than the specification by a factor 2 or 3. The consistencies of the radiometric and spectral performances among the 9 field-of-views (FOVs) that form a field-of-regard (FOR) are better than 0.1 K and 1 ppm, respectively, allowing the NWP weather forecasting models to assimilate data from all the 9 FOVs. The geolocation uncertainty for near nadir pixels is less than 0.4 km in the cross-track and in-track directions. In this presentation, we will provide an assessment of the Validated CrIS SDR product and overview the CalVal process, including the characterizations of radiance noise and uncertainties of spectral and radiometric calibrations and geolocation calculations.