Ionospheric correction based on NeQuick 2 model adaptation to Global Ionospheric Maps

Global Ionospheric Maps (GIMs), computed by Center for Orbit Determination in Europe (CODE) during a period longer than an entire 11 years solar activity cycle, have been used as the primary source of data to provide global ionospheric corrections for possible single frequency positioning applications. The aim of the investigation is to assess the performance of NeQuick 2 model in providing global total electron content (TEC) prediction after ingesting GIMs data from previous day(s). The results show good performance of the GIMs-driven-NeQuick results with average cumulative distribution function (CDF) of vTEC error not to exceed 5 TECU or 20% (zi(20)) near 76.70%. The performance of GIMs-driven-NeQuick also presents variability with solar activity, and behaves better during low solar activity years. There are also seasonal trends of the performance. Generally, zi20 values are bigger in summer and winter and lower in spring and autumn. The differences between in summer and in winter are quite small. And as more measurements from earlier days are used, the accuracies may decrease.