Neutral thermospheric composition and thermal structure

A review of the published experimental works of the past four years is presented. Since 1975, satellite and ground based programs produced new data on the composition and structure of the thermosphere, including the first extensive measurements of a number of minor constituents. The new data were incorporated in a number of semiempirical models which provided an increasingly accurate picture of thermospheric variations. Empirical modelling is considered, followed by solar activity variations, daily variations, magnetic storm variations, measurements of molecular oxygen and minor species, and miscellaneous temperature and density determinations. The concepts of global circulation patterns driven by solar radiation, magnetospheric energy, and momentum sources, and wave sources in the lower atmosphere, and the accompanying redistribution of minor species are outlined.