This paper includes the study of diurnal, monthly, annual and seasonal variation of total electron content TEC at low, mid and high latitude in the Northern Hemispheric region. We have also correlated the TEC variation with the solar proxies viz. $Dst$, $Kp$ index, F10.7~cm and sunspot number. This study was carried out during low solar activity period of 24th solar cycle i.e. from January 2016 to December 2016, at the three latitudes namely Mangilao, US GUUG at 13.44#xB0; N, 144.80#xB0; E, Urumqi, China URUM at 43.82#xB0; N, 87.60#xB0; E, and Ny-Alesund, Norway NYAL at 78.92#xB0; N, 11.86#xB0; E. We observed some unique feature like sinusoidal pattern of diurnal TEC and semiannual oscillation of seasonal TEC. We also observed that the highest values of diurnal and monthly TEC were obtained at low latitude station GUUG Mangilao. It is also seen that maximum seasonal TEC at low, mid and high latitudes was obtained during equinox.
Ionospheric TEC, $Dst$, sunspot number, $Kp$ index
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