Ionospheric TEC variation over Manama, Bahrain and comparison with NeQuick-2 model

This paper presents the ionospheric total electron content (TEC) variation over Manama city of Bahrain using GNSS observables from International GNSS Services (IGS) station at Manama, Bahrain during the period from January 2016 to December 2017. To understand the behavior of TEC variability, the diurnal, monthly and seasonal vertical TEC (VTEC) variations are studied and subsequently compared with NeQuick-2 model estimations. Diurnal VTEC variation reveals a diurnal peak level of about 14 TECU around 09.00UT and declines thereafter to reach a level of about 5 TECU around 20.00UT. However, the comparison study confirms the NeQuick-2 model overestimating the GNSS-VTEC irrespective of time of observation during the day. Monthly behavior of VTEC variation reflects that the NeQuick model is well estimated with GNSS-VTEC during November 2016 and January, February and October months in 2017. The magnitude of variations depicts about 30 to 35 TECU (the highest values) during September 2017 and three continuous months February to April in 2016, while it shows about 10 TECU (the lowest value) during January and December months of 2017, November and December months of 2016. Seasonal VTEC variation shows the underestimation of NeQuick-2 model during the June solstice for the years 2016 and 2017, about 10 TECU. It is notable that NeQuick model shows almost good agreement during the March equinox and December solstice in spite of departure in magnitude difference.