Single-frequency Horizontal GPS Positioning Error response to a moderate Ionospheric storm over Northern Adriatic

Assessment of the real ionospheric impact on GNSS Positioning, Navigation and Timing (PNT) services is essential for identification of vulnerabilities and risks to GNSS performance and operation, as well as to performance and operation of the GNSS- reliant technological and socio-economic systems. Here we present the assessment of the impact of a moderate ionospheric storm on the horizontal component of the single-frequency GPS positioning error in Northern Adriatic. While clearly identifying the effects of a moderate ionospheric storm on northing, easting and horizontal components of GPS positioning error, the results of our analysis show the inexpensive monitoring of the lower ionosphere may provide a feasible means for fast iden-tification of approaching ionospheric-originated GNSS positioning performance disturbances.