Relationship of seasonal behaviours of ionospheric absorption and winds in the high atmosphere

Ionospheric absorption data are correlated with data on the velocity of the zonal wind component to investigate the role of dynamic factors on seasonal variations in ionospheric absorption. The analysis reveals a correlation between seasonal changes in the ionospheric absorption at medium and long wavelengths at mid-latitudes (40-55 deg N) and the wind velocity in the mesosphere, mesopause, and low thermosphere. A connection may exist between mesospheric winds and increases in electron concentration. The reverse dependence upon the equivalent frequency of the summer and winter ionospheric absorption may be conditioned by seasonal reversals in the course of winds above and below the mesopause.