Calibration Validation Of The Cross-track Infrared Sounder (CrIS) With The Aircraft Based Scanning High-resolution Interferometer Sounder (S-HIS)

Climate change detection and potential attribution analyses, as well as Numerical Weather Prediction applications, require rigorous uncertainty analyses following established metrological principles. Using satellite radiance observations, these analyses start with understanding the uncertainties associated with the spectral radiance observations and propagate these and other sources of uncertainty into climate change radiance and geophysical product analyses.

Considering the wide range of existing satellite calibration validation approaches, the high accuracy of aircraft sensors combined with the ability to perform pre- and post-campaign calibration tests to confirm the radiometric performance make satellite under-flight comparisons like those presented here uniquely capable of assessing infrared satellite observations with sufficient accuracy and traceability. The S-HIS has proven to be an extremely dependable and accurately calibrated airborne reference instrument with a well defined radiometric uncertainty and traceability path.

The second Suomi NPP dedicated airborne calibration validation campaign was conducted in March 2015. The primary goals of the campaign are to assess the radiometric calibration and environmental product retrieval for polar conditions. The campaign was conducted out of Keflavik, Iceland with high altitude under-flights of the Suomi-NPP, METOP-A, METOP-B, and NASA Aqua satellites on the NASA ER-2 over the Greenland ice sheet. During this calibration validation campaign, the NASA ER-2 payload consisted of the Scanning-High resolution Interferometer Sounder (S-HIS), the NPOESS Atmospheric Sounder Testbed-Interferometer (NAST-I), the NPOESS Atmospheric Sounder Testbed-Microwave Spectrometer (NAST-M), and the NASA MODIS/ASTER airborne simulator (MASTER).

This presentation will include an overview of the radiance calibration approach, the calibration accuracy and traceability of the S-HIS validation data, a detailed assessment of a single SNPP under-flight, and a summary assessment of the CrIS, IASI-A, IASI-B, and AIRS spectral radiance observations for the under-flights.