AIRS, IASI, and CrIS Comparisons at Dome Concordia in Antarctica

Abstract:

AIRS on EOS-Aqua, IASI on Metop-A, and CrIS on Suomi NPP are three hyperspectral infrared sounders with similar capabilities in polar orbit since 2002, 2007 and 2012 respectively. Their daily overpasses of DomeC within minutes of each other, and the presence of an Automatic Weather Station (AWS8989) at DomeC, provide a great opportunity to compare their absolute calibrations for the 200-260K surface temperature range. We focus on three atmospheric window channels at 900 cm^-1, 1232 cm^-1, and 2508 cm^-1. For these three channels comparison without an explicit correction for differences in their spectral response functions can be made at the 50 mK or better level. The agreement between AIRS, IASI, and CrIS in their mean values is excellent, but differences unique to the design of each instrument are seen for the extreme values.