Effects of zonal and meridional neutral winds on the electron density and temperature at the height of 600 km

Electron temperature (Te) and density (Ne) data which were obtained with equator-orbiting satellite Hinotori in 1981-1982 at the height of 600 km are used to study the local time, latitude, longitude, and seasonal variations of the topside ionosphere at low latitudes. The study shows that difference of behavior of the daytime Te and Ne between two hemispheres is well understood by the effect of neutral wind. Electron density in the summer hemisphere is higher than that in winter hemisphere due to meridional wind component (seasonal variation) which blows from summer hemisphere to winter hemisphere and consequently electron temperature is lower in summer hemisphere than in winter hemisphere. In addition to this effect, effect of the zonal wind component (diurnal change) is superposed at the regions where magnetic meridian plane tilts. Especially in the American sector, where magnetic meridian plane tilts about 20 degrees westward, zonal wind effect is comparable to the meridional wind effect.
JAXA Research and Development Report
宇宙航空研究開発機構研究開発報告