A spatial and temporal comparison of Five Total Electron Content providers

The Total Electron Content (TEC) is an important part for the GNSS community and the users because of their effect on the obtained accuracy for computing the higher order ionospheric delay and the study of the ionosphere layer. Many analysis centres are generating those TEC values on daily basis. This can provide the users with different alternatives TEC values for the same location. Thus, this paper critically tries to investigate the generated TEC values from four scientific analysis centres (ACs). Those ACs are COD, ESA, JPL and WHU. A temporal for one year (2018), and spatial for -87.5 to 87.5 latitude and from -180 to 180 longitude TEC values statistical comparison have been investigated to understand the accuracy level of the four provided products. Those value have been compared to the international GNSS Service (IGS) TEC values for the same temporal and spatial resolution. Four-time scale in the day have been examined in this analysis to cover different times for one day. The statistical results show that all the differences from the four ACs comparing to the IGS could reach accuracies within ∼1 TECu which is equivalent to 1/3 nanosecond.