Investigating the Performance of IGS Real-Time Global Ionospheric Maps under Different Solar Conditions

In recent years, real-time global ionospheric map (RT-GIM) products have been actively developed by the international navigation satellite system (GNSS) service (IGS) and its ionosphere associate analysis centers (IAACs) along with increase of RT-GNSS multi-frequency multi-constellation observations. this study, accuracy consistency three RT-GIM from Chinese Academy Sciences (CAS), Wuhan University (WHU), IGS are evaluated analyzed utilizing validation methods, namely, comparison JASON-3 vertical total electron content (VTEC), difference slant (dSTEC), combined final GIM (IGSG) data. The test period was 1 January 2019 to 31 December 2022, including different solar activities. First, data illustrates that quality over oceans is in great IGSG during levels activity daily mean bias (MEAN) values low high activities approximately 5 10 TECU, respectively. root square (RMS) under can be up 7 12 TECU. Furthermore, dSTEC results present MEAN IAACs at high- mid-latitude stations about 0.5 which smaller than those low-latitude TECU continental regions. standard deviation (STD) RMS for various within 3 4 latitudes, terms IGSG, result shows (IRTG) presents better CAS (CRTG) WHU (WRTG) 2021 average annual STD 2.56 2.78 biases relative reach mainly 6 range,