Abstract
The Cross-track Infrared Sounder (CrIS) was successfully launched onboard of Suomi National Polar-orbiting Partnership (S-NPP) in October 2011. It is a hyperspectral FTIR instrument with 1317 spectral channels. The spectral sampling is 0.625 cm-1 for the long-wave band, 1.25 cm-1 for the mid-wave band, and 2.5 cm-1 for the shortwave band. On March 12, 2013, 5 orbits of high spectral resolution CrIS spectra were collected. The spectral resolution for all three bands is 0.625 cm-1 (with a total number of 2211 channels). Since the operational EDR algorithm uses normal spectral resolution radiative transfer model, we have trained a spectral version of a Principal Component-based Radiative Transfer Model (PCRTM), which calculates the full resolution CrIS radiances. We will compare the observed CrIS brightness spectra with those calculated using the PCRTM model. The geophysical parameters will be taken from both the CrIMSS EDR product and from the spatial-temporal matched NWP models. The differences between the observations and PCRTM calculations will be discussed and potential of using RT model for radiance validation will be evaluated.
Comparison of Full-resolution S-NPP CRIS Radiance with Radiative Transfer Calculations
The Cross-track Infrared Sounder (CrIS) was successfully launched onboard of Suomi National Polar-orbiting Partnership (S-NPP) in October 2011. It is a hyperspectral FTIR instrument with 1317 spectral channels. The spectral sampling is 0.625 cm-1 for the long-wave band, 1.25 cm-1 for the mid-wave band, and 2.5 cm-1 for the shortwave band. On March 12, 2013, 5 orbits of high spectral resolution CrIS spectra were collected. The spectral resolution for all three bands is 0.625 cm-1 (with a total number of 2211 channels). Since the operational EDR algorithm uses normal spectral resolution radiative transfer model, we have trained a spectral version of a Principal Component-based Radiative Transfer Model (PCRTM), which calculates the full resolution CrIS radiances. We will compare the observed CrIS brightness spectra with those calculated using the PCRTM model. The geophysical parameters will be taken from both the CrIMSS EDR product and from the spatial-temporal matched NWP models. The differences between the observations and PCRTM calculations will be discussed and potential of using RT model for radiance validation will be evaluated.