Article

Stratospheric N2O5, CH4, and N2O profiles from IR solar occultation spectra

CNRS Université Pierre and Marie Curie; NASA Langley Research Center; University of Denver
Journal of Atmospheric Chemistry (Impact Factor: 1.33). 12/1992; 16(1):31-40. DOI: 10.1007/BF00696622

ABSTRACT Stratospheric volume mixing ratio profiles of N2O5, CH4, and N2O have been retrieved from a set of 0.052 cm–1 resolution (FWHM) solar occultation spectra recorded at sunrise during a balloon flight from Aire sur l'Adour, France (44 N latitude) on 12 October 1990. The N2O5 results have been derived from measurements of the integrated absorption by the 1246 cm–1 band. Assuming a total intensity of 4.3210–17 cm–1/molecule cm–2 independent of temperature, the retrieved N2O5 volume mixing ratios in ppbv (parts per billion by volume, 10–9), interpolated to 2 km height spacings, are 1.640.49 at 37.5 km, 1.920.56 at 35.5 km, 2.060.47 at 33.5 km, 1.950.42 at 31.5 km, 1.600.33 at 29.5 km, 1.260.28 at 27.5 km, and 0.850.20 at 25.5 km. Error bars indicate the estimated 1- uncertainty including the error in the total band intensity (20% has been assumed). The retrieved profiles are compared with previous measurements and photochemical model results.

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