Nighttime O(<sup>1</sup>D) distributions in the mesopause region derived from SABER data

Abstract

<jats:p>Abstract. In this study, the new source of O(1D) in the mesopause region due to the process OH(ν ≥ 5) + O(3P) → OH(0 ≤ ν’ ≤ ν-5) + O(1D) is applied to SABER data to estimate the nighttime O(1D) distributions for the years 2003–2005. It is found that O(1D) evolutions in these years are very similar to each other. Depending on the month, monthly averaged O(1D) distributions demonstrate from 2 to 4 maxima with the values up to 340 cm−3 which are localized in height (at ~ 92–96 km) and latitude (at ~ 20–40° S,N and ~ 60–80° S,N). Annually averaged distributions in 2003–2005 have a one weak maximum at ~ 93 km and ~ 65° S with the values of 150–160 cm−3 and 3 pronounced maxima (with the values up to 230 cm−3) at ~ 95 km and ~ 35° S, at ~ 94 km and ~ 40° N, at ~ 93 km and ~ 65–75° N correspondingly. In general, there is slightly more O(1D) in the northern hemisphere than in the southern hemisphere. The obtained results are useful data set for subsequent estimation of nighttime O(1D) influence on chemistry of the mesopause region. </jats:p>