Use of GNSS derived ionospheric information to detect and measure Solar Flares

Abstract

The Ionosphere, the partially ionized atmospheric region ranging from approximately 60 to +1000 km height, is typically affected by spatial and temporal variations, driven by Local Time (solar illumination), Latitude (magnetic field and solar illumination) and time (space weather, among seasonal and solar cycle dependence). It can be indirectly studied from the dual L-band frequency GNSS measurements by assuming the first order ionospheric delay approximation (the higher order ionospheric effects in GNSS typically constitute less than 0.1% of the overall ionospheric effect and only affects very precise applications). Moreover, the Ionosphere is affected as well by ionospheric waves, ,solar flares and other space weather effects. Recent modeling techniques and corresponding results are going to be summarized regarding to the daylight sudden overionization generated by the radiation associated to Solar Flares facing the Earth, and its measurement by means of Global Navigation Satellite Systems. This approach has already been implemented in real-time by the authors.