Inferring middle-atmospheric ozone height profiles from ground-based measurements of molecular oxygen emission rates, I: Model description and sensitivity to inputs

Abstract

Improvements in the sensitivity and automation of high-resolution, ground-based spectrometers and interferometers allow the routine acquisition of measurements not only in the nightglow, but in the twilight. Measurements of the emission rate of the O2(1Δg) and O2(1Σg) bands have been used, primarily in the dayglow, to infer mesospheric O3 profiles. This paper describes a model for the inversion of twilight O2(1Δg) and O2(1Σg) emission-rate measurements to obtain O3 height profiles, concentrating on the sensitivity of the results to temperature profile, solar flux, photodissociations rates, uncertainties in the reaction rates, and constants, and the importance of transfer chemistry as a contribution to the O2(1Δg) emission rate, using a fixed O3 profile. The sensitivity of the calculations to inputs other than the desired O3 density shows this method may not be suitable for the absolute value of the O3 density (to better than about 25%), but can successfully determine the shape of the O3-density profile in the middle atmosphere.