Theoretical description of the main neutral constituents in the earth's upper atmosphere

The solution of time-dependent continuity and motion equations for the main neutral constituents O, O 2 and N 2 has been obtained and compared with different approximations. Numerical calculations have been carried out for different solar fluxes and eddy diffusion coefficients in the altitude range 80–300 km. The O and O 2 height profiles obtained differ considerably from profiles calculated using the approximation of minor constituent diffusion and the approaches developed by Friedman (1967) and Colegrove et al. (1965). This discrepancy increases with an increase of eddy diffusion and solar flux. The ratio O O 2 calculated in this work may differ from that deduced from these approximate approaches by about 50%.