Abstract:
This thesis is aimed to study diurnal, monthly, seasonal and annual variation of
ionospheric TEC obtained from GPS satellite in the years of 2007 to 2017. TEC data
measured by dual frequency signals of the Global Position System (GPS) in Bahir
Dar Ethiopia low latitude station, with geographic latitude (11.6
0N) and Longitude
(37.350E) during the years 2007 to 2017. The results showed that the hourly and
diurnal variation TEC minimum between 23:00 LT to 06:00 LT and 17:00 to 23:00
LT; maximum at about 12:00 to 14:00 LT or As regard to monthly variations of
ionospheric TEC, results of GPS satellite showed that highest mean TEC values were
recorded on March, April, October and September then July recorded the least peak
TEC values. The seasonal variation of TEC maximized during the equinox months
followed by winter months. Especially Jun solstices were least TEC values. We have
also seen between TEC with geomagnetic activity and solar activity. Finally we have
investigated the long term variation of TEC over Bahir dar Ethiopia.
Key words :Ionospheric Total Electron Content(TEC), Low Latitude or Equatorial
Station, Diurnal, Monthly, Seasonal, variation.