An experiment using high resolution CrIS measurements for atmospheric retrievals: carbon monoxide impact study

We perform a demonstration experiment using the NOAA Unique CrIS/ATMS Processing System to assess the improvement on trace gas retrievals upon switching to high resolution CrIS radiance measurements (0.625 cm^-1). The focus of this study is carbon monoxide retrievals. The experimental high resolution CO retrievals show a remarkable improvement, of almost up to one order of magnitude in the degree of freedom of the signal, with respect to the low resolution mode. Furthermore, high resolution CO retrievals show similar skill with respect to existing CO operational products from the AIRS, IASI and MOPITT instruments, both in terms of spatial variability and degrees of freedom. The results of this research provide evidence to support the need for high resolution CrIS measurements. This is a fundamental prerequisite in guaranteeing continuity to the CO afternoon orbit monitoring as part of a multi-satellite, uniformly integrated, long term data record of atmospheric trace gases.