Enhancements to the Crosstrack Infrared Sounder (CrIS) for Improved Radiometric Accuracy

摘要

The Crosstrack Infrared Sounder (CrIS) is one of the key sensors now under development for the National Polar-orbiting Operational Environmental Satellite System (NPOESS) program, which is the follow-on to the current DMSP and POES meteorological satellite systems. CrIS is a interferometric sounding sensor which accurately measures upwelling earth radiances at very high spectral resolution, and uses this data to construct vertical profiles of atmospheric temperature, moisture and pressure. The purpose of this paper is to examine small modifications to the CrIS design that enable it to be used for other applications where improved radiometric uncertainty is required. Modifications include changes to the onboard calibration target and onboard calibration systems, as well as enhancements to ground calibration algorithms that remove additional sources of radiometric error. An assessment is also made of the level of improvement in radiometric uncertainty that can be expected.