Ionospheric electron density perturbations during the 7-10 March 2012 geomagnetic storm period

In order to assess the capability of the ionospheric profiler called Topside Sounder Model - assisted Digisonde (TaD model) to detect such perturbations in the electron density, electron density disturbances at heights from 200 to 1000 km have been calculated with the TaD model and compared with slant TEC parameters obtained from GPS receivers co-located with the Digisondes whose data were used to generate the TaD model predictions. The model matches in qualitative terms the GPS TEC observed perturbations independently from the source. The physical mechanisms that govern the ionosphere, such as ion drag by neutral winds along magnetic field lines, E × B drifts, and increased recombination due to the neutral composition changes, offer various combinations of foF2, hmF2 and TEC variations, which TaD resolves. Counterwise, TaD can help the interpretation of various physical scenarios which cannot be achieved if solely TEC or F layer variations are considered.