## 3 Results and Analyses
Finally, we can observe one more storm that began at 16:00 UT on 27 February, showing a minimum SYM-H of \(-99\) nT at 00:00 UT on 28 February. Due to the isolated character of this last storm, it was not investigated. Figure 1: Solar wind and space weather conditions during the storm of February 2014 from different indices: (**a**) solar flux, (**b**) SW plasma temperature, (**c**) SW proton density and SW plasma pressure, (**d**) SW plasma beta parameter, (**e**) SW plasma density ratio between alpha and proton, (**f**) SW speed, (**g**) IMF B\({}_{x}\) component and total field, (**h**) merging (E\({}_{\rm{m}}\)) and eastward zonal (E\({}_{y}\)) electric fields, (**i**) AE index, and (**j**) SYM-H and Am index (in red). The SSCs and HSSW are highlighted with vertical yellow and green lines, respectively. The TEC responses were investigated with the analysis of data from permanent GNSS stations located at similar geomagnetic longitudes and at slightly shifted latitudes in the equatorial region of Africa. Figure 2 shows the effects of the multiphase storms on the low latitude ionosphere of the Africa sector and the GNSS TEC and rTEC change for the MAL2, NKLG, BKFP, RABT, and CLBR stations. The locations of these stations are shown in Table 1. The TEC diurnal variation shows the characteristic pre-dawn minimum followed by an early morning increase that reaches a maximum after noon, with TEC values between 40 and 70 TECU with respect to the night side, depending on the station. Then, clear rTEC enhancements above 60% appeared during the HSSW on 19 February at NKLG. The TEC responses from these stations are highly different and show complex patterns. On the SSC of 20 February, the MAL2 indicates a clear depletion, whereas, at the same time, the other stations show enhanced rTEC above 60%. TEC disturbances (\(1\,r\)TEC \(|\geq 30\%\)  
Figure 2: Low latitude TEC variations (**a,c,e,g,i**). The black lines show TEC median (background); blue bins (**b,d,f,h,j**) show the relative TEC percentage of disturbance. The SSCs and HSSW are highlighted with vertical yellow and green lines, respectively. dominate during the main-phase periods and may be related to thermospheric neutral winds propagating to low latitudes. Note also MAL2 shows a large depletion on 20 February and a second peak on 21 February in the night side. The TEC variations at NKLG and CLBR stations are 24 h delayed in the enhancements at the night side from 20 to 24 February, showing an EIA expansion to lower latitudes; both stations are located in the southern hemisphere but separated by approximately 4 degrees in latitude. However, the TEC variations at BKFP (also located at the southern hemisphere) show TEC depletions at the night side during the analyzed period, which turn to positive enhancements from 20 to 24 February, following a similar pattern to that seen at CLBR. The TEC variations at the RABT station show enhancements from 19 to 22 February at the noon side, and very prompt enhancements are seen after 23 February, showing a clear drift to higher latitudes. The EEJ and PPEF vary significantly after the SSCs and HSSW for all the events in all the longitudinal sectors (Figures 3 and 4). In Figure 4, the evening peak in PPEF corresponds to the pre-reversal enhancement of the eastward electric field near sunset, which is at the origin of the peak in TEC at MAL2 (Figure 2). The most significant EEJ perturbations occurred in the African sector during the main phase of the storm on 19 to 20 February, with values below 50 nT. At this point, the effect of the disturbance dynamo clearly produces a reversed EEJ. The EEJ varied mostly in the American and African sectors during the main phase of the 19 to 20 February geomagnetic storm. Minor EEJ variability is seen in the Asian sector, probably due to the lower fluctuation captured by the experiment, although the PPEF perturbations are very prominent in all the sectors for all the SSCs and the HSSW events, with absolute values above 0.2 mV/m.