Optical characteristics of the thermosphere and mesosphere

Using lidar signals at wavelengths of 561 and 532 nm in the altitude range of 30-400 km, by solving the inverse problem, we restore the light scattering coefficients corresponding to these wavelengths, which makes it possible to compare the optical characteristics of the thermosphere, mesosphere and upper stratosphere and determine the relationship between the resonant, Rayleigh and aerosol scattering of light at different altitudes of the atmosphere. Using the scattering coefficients in the thermosphere, we find the cross sections of light scattering at wavelengths of 561 and 532 nm for the transitions of excited atomic oxygen and nitrogen ions and explain why the scattering coefficients for O+, 561 nm are smaller than for N+, 532 nm, while the concentration of O+ is two orders of magnitude higher than N+. The results obtained here are of interest for understanding the ionization effect of solar activity on the optical characteristics of the atmosphere, which determine weather and climate changes.