Abstract. The diurnal, seasonal and latitudinal variations of electron temperature T_e, measured by the SROSS C2 satellite at equatorial and the low-latitudes during the low solar activity period of 1995–1997 are investigated. The average height of the satellite was ~ 500 km and it covered the latitude belt of –31° to 34° and the longitude range of 40°–100°. T_e varies between 700–800 K during night-time (20:00–04:00 LT), rises sharply during sunrise (04:00–06:00 LT) to reach a level of ~ 3500 K within a couple of hours and then falls between 07:00–10:00 LT to a daytime average value of ~ 1600 K. A secondary maximum is observed around 16:00–18:00 LT in summer. Latitudinal gradients in T_e have been observed during the morning enhancement and daytime hours. Comparison of measured and International Reference Ionosphere (IRI) predicted electron temperature reveals that the IRI predicts nighttime T_e well within ~ 100 K of observation, but at other local times, the predicted T_e is less than that measured in all seasons.

Key words. Ionosphere, equatorial ionosphere, plasma temperature, and density