HITRAN spectroscopy evaluation using solar occultation FTIR spectra

- Atmospheric spectra were fitted to assess HITRAN׳s quality and completeness.
- HITRAN 2012 represents a significant improvement over previous versions.
- Spectral regions where HITRAN 2012 under-performs are investigated further.

High resolution FTIR solar occultation spectra, acquired by the JPL MkIV Fourier transform spectrometer from balloon, covering 650-5650 cm−1 at 0.01 cm−1 resolution, are systematically analyzed using the last four versions of the HITRAN linelist (2000, 2004, 2008, 2012). The rms spectral fitting residuals are used to assess the quality and adequacy of the linelists as a function of wavenumber and altitude. Although there have been substantial overall improvements with each successive version of HITRAN, there are nevertheless a few spectral regions where the latest HITRAN version (2012) has regressed, or produces residuals that far exceed the noise level. A few of these instances are investigated further and their causes identified. We emphasize that fitting atmospheric spectra, in addition to laboratory spectra, should be part of the quality assurance for any new linelist before public release.