Diurnal Variation of Ionospheric Electron and Ion Temperatures with Altitude by QJISR

The ionospheric plasma temperatures in March and June measured by the Qujing incoherent scatter radar have been used to study the diurnal variation of electron and ion temperatures with altitude (193-513km). It is found that there exist the morning and sunset enhancement and the daytime constant valley in electron temperature in March. The features like morning overshoot, day time valley (about 1000K) and sunset enhancement (with the maximum 3500K) show larger values at higher altitudes. The electron temperature above 1000K decreases with an increase in density. The sunset peak occurs earlier at higher altitudes. These above characteristic isn't prominent for electron temperature in June and ion temperature in all seasons. Both the electron and ion temperature reach a peak at about 200km and then decreases. The possible mechanism is also presented.