Modelling Ionospheric Phenomena and Assessing the Performance of IRIPlas2017 during Different Phases of Solar Cycle 24

Ionospheric modelling is one of the most powerful tools for studying the behavior of the ionosphere. The aim of this paper is to assess the performance of IRI-Plas2017 in five different longitudinal sectors during different phases of solar cycle 24 (2011–2017). An hourly mean value of Total Electron Content (TEC) was used to study the diurnal and seasonal variations in TEC. An annual error plot profiled on monthly basis was used to study the difference between the measured and predicted TEC values. The annual TEC deviations were used to investigate the relationship between TEC derived from Global Positioning System (GPS) and IRI-Plas2017 model. Our results showed that the highest peak value of TEC was recorded as ~89 TECU (06:00UT) in the Asian sector (BAKO) while the lowest peak value of ~22 TECU (08:00UT) was recorded in the Australian sector (DAV1) in the ascending and descending phase during the March equinox respectively. Semi-Annual variation is a prevailing factor in all the solar cycle phases in the Africa and Asian sectors except during the descending and maximum phase where anomalies were recorded. Semi-annual anomalies were also prominent in all the solar cycle phases in the Australian, American, and Asian sectors. Winter anomaly was predominant in all the phases of solar cycle in the American, Asian, and European sectors. However, the IRI-Plas2017 model was not able to appropriately reproduce the two prominent phenomena (Semi-annual Variations and Winter Anomalies) observed in all the five longitudinal sectors.