“…The ionospheric temperatures also show variation associated with diurnal, seasonal, latitudinal, longitudinal altitude and in an 11-year solar cycle (Mahajan et al, 1983;Oyama et al, 1996a;Richards, 2001;Sharma et al, 2003b). The change in ionospheric temperatures may affect the radio communication, navigation, exploration of near Earth space, electronic systems in satellites and spacecraft (Kazimirovsky et Correspondence to: D. K. Sharma (dksphdes@iitr.ernet.in) al., 2003).…”