Global mapping of minor atmospheric constituents with AIRS on EOS

The Atmospheric Infrared Sounder (AIRS) is a grating-array spectrometer on EOS. It covers the region from 650 to 3000/cm with spectral resolution of 1200. The prime objective of AIRS is the global retrieval of temperature and water vapor profiles and of surface temperatures. The wide spectral coverage of AIRS permits the measurement of a number of additional atmospheric and surface parameters. Of particular interest is the potential to produce daily global maps of the spatial distribution of the more abundant of the minor gases, e.g. ozone, CO, CH4, and N2O. This potential capability for CH4 and N2O is strongly affected by cloud residual. Using the CH4 band at 1306/cm as example, spatial averaging of AIRS data is required to measure a 10 percent change in the nominal CH4 column abundance. At 1300/cm, this requires cloud clearing at the 0.3 percent level. The mapping capability for ozone and CO in terms of rural/urban abundance patterns is not likely to be impacted with cloud-clearing residuals as high as 5 percent.