Quantifying uncertainties in Atmospheric Infrared Sounder (AIRS) spatial response functions (SpatialRFs) is critical for enhancing the quality of climate data records. Previously, AIRS in-flight SpatialRF calibrations have utilized an incomplete set of pre-flight data obtained during instrument assembly. In our current work, we combined various pre-flight data sets to interpolate a complete set of pre-flight SpatialRFs. Concurrently, we employed two consecutive days of AIRS and Moderate Resolution Imaging Spectroradiometer (MODIS) data to independently retrieve in-flight SpatialRFs for multiple channels and scan angles. Our methodology, based on our previous work, aligns AIRS and MODIS radiances to derive spatially corrected SpatialRFs. This paper compares in-flight SpatialRFs obtained from consecutive days and examines the discrepancies between pre-flight SpatialRFs from a completed set and in-flight SpatialRFs. Employing the total variation distance metric with two days of consecutive data revealed that the average uncertainties in in-flight SpatialRFs are approximately 5%, attributed mainly to noise, which establishes a baseline. In contrast, pre-flight SpatialRFs displayed an average uncertainty of about 16% when compared to the values derived in-flight. Our findings underscore the value of reconstruction techniques to derive in-flight SpatialRFs to validate pre-flight measurements, which is vital for ensuring the long-term reliability and precision of climate data records obtained from AIRS.
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