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Consistency of seven different GNSS global ionospheric mapping techniques during one solar cycle


In the context of the International GNSS Service (IGS), several IGS Ionosphere Associated Analysis Centers have developed different techniques to provide global ionospheric maps (GIMs) of vertical total electron content (VTEC) since 1998. In this paper we present a comparison of the performances of all the GIMs created in the frame of IGS. Indeed we compare the classical ones (for the ionospheric analysis centers CODE, ESA/ESOC, JPL and UPC) with the new ones (NRCAN, CAS, WHU). To assess the quality of them in fair and completely independent ways, two assessment methods are used: a direct comparison to altimeter data (VTEC-altimeter) and to the difference of slant total electron content (STEC) observed in independent ground reference stations (dSTEC-GPS). The main conclusion of this study, performed during one solar cycle, is the consistency of the results between so many different GIM techniques and implementations.

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This work has been possible thanks to the collaborative and friendly framework of the International GNSS Service, an organization providing first class open data and open products to the scientific and technical GNSS communities (see Dow et al. 2009). We appreciate the editorial inputs of Dr. René Zandbergen from ESA/ESOC.

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Correspondence to Manuel Hernández-Pajares.

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Roma-Dollase, D., Hernández-Pajares, M., Krankowski, A. et al. Consistency of seven different GNSS global ionospheric mapping techniques during one solar cycle. J Geod 92, 691–706 (2018). https://doi.org/10.1007/s00190-017-1088-9

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  • Global navigation satellite systems
  • Ionosphere
  • Global ionospheric maps
  • Vertical total electron content
  • Model validation