Pressure-broadening coefficients and line strengths of H2O near 1.39 µm: application to the in situ sensing of the middle atmosphere with balloonborne diode lasers

Georges Durry (1, 2) , Virginie Zéninari (2) , Bertrand Parvitte (2) , Thibault Le Barbu (1, 2) , Franck Lefèvre (1) , J. Ovarlez (3) , R.-R. Gamache

1 SA - Service d'aéronomie
2 GSMA - Groupe de spectrométrie moléculaire et atmosphérique
3 LMD - Laboratoire de Météorologie Dynamique (UMR 8539)

Since 1998, we have developed two balloonborne diode laser spectrometers, SDLA and micro-SDLA, to yield in situ concentration data of H2O in the middle atmosphere by absorption spectroscopy in the 1.39-É m spectral range. In this paper, we revisit the molecular parameters, line intensities and pressure-broadening coefficients, for several lines of the ÉÀ1+ÉÀ3 and 2ÉÀ1 bands, which are useful for the monitoring of atmospheric H2O. The new values are thoroughly compared to existing molecular database and previous determinations. Calculations are performed to yield the pressure-effect coefficients: the theoretical model is described and the ab initio predictions are compared to laboratory measurements achieved with a laser diode spectrometer. The improvement in the H2O monitoring obtained with the new set of molecular data is evaluated directly from vertical H2O concentration profiles.

Mots clés: Atmosphère moyenne; Vapeur eau

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

Georges Durry, Virginie Zéninari, Bertrand Parvitte, Thibault Le Barbu, Franck Lefèvre, et al.. Pressure-broadening coefficients and line strengths of H2O near 1.39 µm: application to the in situ sensing of the middle atmosphere with balloonborne diode lasers. Journal of Quantitative Spectroscopy and Radiative Transfer, 2005, 94, pp.387-403. ⟨10.1016/j.jqsrt.2004.09.033⟩. ⟨hal-00076836⟩