Comprehensive analysis of the ionospheric response to the largest geomagnetic storms from solar cycle 24 over Europe

A multi-instrumental analysis of the meridional ionospheric response is presented over Europe during two largest ICME-driven geomagnetic storms solar cycle #24 maximum. Data from 5 European digisonde stations, ground-based Global Navigation Satellite System, Total Electron Content (GNSS TEC), ratio TEC difference (rTEC), as well Swarm and Thermosphere, Ionosphere, Mesosphere, Energetics Dynamics (TIMED) satellite observations have been used for investigation selected intervals (11–17 November, 2012, 16–25 March, 2015). The storm evolution monitored by foF2 critical frequency (related to maximum electron density F2-layer) GNSS data. Moreover, Ultraviolet Imager (GUVI) measurements TIMED are investigate changes in thermospheric O/N 2 ratio. Our main focus was on phase storms, when nighttime hours extremely depleted plasma detected. extreme depletion observed foF2, rTEC, which found be directly connected equatorward motion midlatitude trough (MIT) nightside. We demonstrate a method (beside existing ones) allows monitoring storm-time disturbances (e.g., MIT, SAPS, SED) thermosphere-ionosphere-plasmasphere system combined worldwide data (with drift layer parameters with 5–15 min cadence), rTEC data, like Swarm, TIMED/GUVI.