Early results from AIRS on the EOS

The Atmospheric IR Sounder (AIRS) on the EOS Aqua spacecraft is an IR spectrometer/radiometer which covers the 650-2700 cm-1 region of the spectrum with 2378 spectral channels. The EOS Aqua was launched on 4 May 2002 from Vandenburg AFB, California, in to a 705km high, sun synchronous orbit. First test of the radiometric calibration using the analysis of (observed-calculated) for data from a single, relatively cloud free 2500×2500 km area of the subtropical Atlantic ocean confirm absolute radiometric accuracy of better than 0.5K. The spectral information in the data also suggests that the analyzed region contained more moisture than the NCEP analysis. Based on these results we expect that the assimilation of AIRS data into the forecast to result in major medium range weather forecast improvements and that the data set recorded by AIRS during its nominal seven year lifetime will be a major resource for climate studies.