DYNAMICS OF F-REGION OBSERVED WITH THOMSON-SCATTER .I. ATMOSPHERIC CIRCULATION AND NEUTRAL WINDS

Since June 1966, results from the French Thomson-scatter bistatic sounder (SaintSantin-Nançay) have yielded a considerable amount of data for the study of ionization transports in the F-region of the ionosphere. The first section of this paper brings out the importance and scale of transports in the ionosphere, and describes the new method of measurement used at Nançay. In the second section, experimental results of about 20 diurnal variations as described by hourly values of velocities are presented. Section 3 interprets these velocities as the sum of two effects: horizontal circulation of the neutral air, and ambipolar diffusion of ionization under gravity and under its own partial pressure. The two effects can be separated, giving an evaluation of neutral atmosphere velocities. © 1969.