Measurement of nighttime stratospheric N2O5 from infrared emission spectra

Abstract
The mixing ratio profile of N2O5 has been inferred from high‐resolution emission spectra obtained with a balloon‐borne Fourier spectrometer (SIRIS). The observations were taken for the period from midnight to predawn on September 16, 1986 at 32° N latitude. The inferred volume mixing ratio from nighttime average spectra has a peak of ∼ 1.8 × 10−9 in the 32‐35 altitude range. The inferred mixing ratio is generally less than the theoretical predictions from a 1‐D model.