Effect of solar activity on diurnal and seasonal variations of electron temperature measured by the SROSS C2 over Indian low latitudes

Effect of solar cycle on topside ion temperature measured by SROSS C2 and ROCSAT 1 over the Indian equatorial and low latitudes

“…It is seen from the figure that ion temperature shows insignificant positive correlation over all the three latitudes during daytime, while during nighttime the ion temperature is negatively correlated with solar flux. Increase in electron temperature with increase in F 10.7 cm solar flux has been reported by Bhuyan et al (2006) from a study of the solar cycle variation of T e measured by SROSS C2 and ROCSAT 1 from 1995 to 2003 during solar cycle 23. Similarly positive correlation between T e and solar flux has been found by Oyama (1994) for nighttime T e .…”

“…Therefore, the electron temperature (T e ) profile at a particular location reflects to some extent the behaviour of ion temperature. Bhuyan et al (2006) examined the temporal variation of electron temperature measured by the SROSS C2 at ∼500 km altitude during the period of 1994-1998 and found that electron temperature varies between 700-900 K during nighttime, rises sharply in the sunrise period to reach a level of 3500-5000 K, and then falls within the next few hours to a daytime average level of 1600-2000 K. A secondary maximum in electron temperature is observed in the afternoon to early evening period in summer in all years and in the equinoxes in moderate solar activity period. The morning enhancement was found to be more pronounced in the equinoxes and between the solstices; winter enhancement was more compared to that in summer.…”

Variation of ionospheric electron and ion temperatures during periods of minimum to maximum solar activity by the SROSS-C2 satellite over Indian low and equatorial latitudes

“…Another advantage of SROSS-C2 mission is that the orbit is just above the F-region electron density peak and the orbital ellipticity is much less. Many researchers (Bhuyan et al, 2002(Bhuyan et al, , 2004(Bhuyan et al, , 2006Aggarwal et al, 2009) have also used the SROSS-C2 satellite data to study the behavior of ionospheric parameters. Bhuyan et al (2004) studied the diurnal, seasonal and latitudinal variations of the ion temperature using the SROSS-C2 satellite data in the Indian zone equatorial and low latitude ionosphere at an average altitude 500 km.…”

Diurnal, seasonal, latitudinal and solar cycle variation of electron temperature in the topside F-region of the Indian zone ionosphere

“…Mahajan and Pandey (1979) found that T e at 1000 km increased with solar activity between 1965 and 1969. Using SROSS C2 data for the low to moderate solar activity period of -1998, Bhuyan et al (2006 had recently reported a positive correlation between electron temperature and F10.7 for both daytime and nighttime at 500 km over 10 • N of the geomagnetic equator. The amplitude of the morning and afternoon enhancements in T e varies with solar activity.…”

“…Bhuyan et al (2002a, b) have reported SROSS C2 electron temperature measurements over Indian low and equatorial latitudes using this database. Bhuyan et al (2006) have reported the effect of solar activity on local time and seasonal variations of electron temperature measured by the SROSS C2 during the low to moderate solar activity period from 1995 to 1998 over the Indian subcontinent and compared the data with that of the International Reference Ionosphere (IRI-2001) model.…”