Neutral Wind. & Nighttime F-region

Abstract

Time-dependent equations of motion for the neutral particles have been solved for day and· night, and continuity equation for electron density for the nighttime, using known electron density profiles over a midlatitude station-Puerto Rico. Estimates of neutral winds and protonospheric fluxes have been made for four typical seasons of the year. The observed <i>hm </i> and <i>Nm </i> variations for the various seasons during the nighttime are in good qualitative agreement with the reversal times of the neutral wind motion towards the equator ward direction and the magnitude of the protonospheric flux. It is suggested that for a proper understanding of the maintenance of the nighttime F-region ionization, it is important to consider the following four parameters: the maximum electron density <i>(Nm), </i> the peak of ionization <i>(hm), </i> the day-to-night increase in <i>hm, </i> and the ratio of day-to-night <i>Nm.</i>