Attività solare, effetti ionosferici e servizi NRTK: quali connessioni?

As recognized by hundreds of years of sun observation by the researcher in eliophysics, the Sun is now entering in a period of increased activity. The producing of sunspots, solar flares and coronal mass ejection from the Sun’s surface is able to create anomalies in the magnetic field that could stream towards the Earth. The terrestrial magnetic field may be influenced by the “solar wind” and the ionized upper layer of the atmosphere, called ionosphere, could be affected by scintillation and induced delays of the travelling signals. Several critical infrastructures would be influenced by such a disturbance. The 11-years long cycle of solar activity is expected to reach the peak by the middle of the year 2013 and possible effects on the GNSS (Global Navigation Satellite System) services have to be accounted for. This is because of the properties by the ionospheric layers to delay the GNSS signals depending on the electron density within the ionospheric strata. This study focuses on the effects of the ionospheric disturbance on the NRTK (Network Real Time Kinematic) services through the analysis of the performances achieved by the users during the year 2011, when a fast rising in ionospheric activity was recorded by the end of the year. A relationship between the reliability of positioning and the ionospheric activity was found.