## 4 Discussion on the Corresponding Processes in Ionosphere
### The Comparison of Plasma Parameters at Different Altitudes
In the European sector, due to the low values in TEC from CODE at middle latitudes, no obvious increase occurred at latitudes of 45-60\({}^{\circ}\) N, as shown in [20], on 26 August, but in the African sector, the equatorial increase was significant at LT09 and 11 on 26 August and at LT13 and 15, even continuing, on 28 August, as shown in Figure 8. Based on the observations from Jason satellites at altitudes of about 1330 km, the evening equatorial ionospheric anomaly (EIA) were illustrated around LT21 at the Pacific region of longitudes 180-150\({}^{\circ}\) W during the main phase on 26 August [25]. In comparison with the nighttime Ne at altitude of 507 km from CSES in Figure 5, Ne at low and middle latitudes indeed increased at the main phase on 26 August, but the two peaks at latitudes of 20-40\({}^{\circ}\) were not newly constructed, due to this magnetic storm on 26 August relative to those on 24 and 25 August. The enhanced EIA was obviously presented in the dayside from Ne of CSES and Swarm satellites in Figures 6 and 7, and at the Asian sector of longitudes 60-120\({}^{\circ}\) E from TEC of CODE in Figure 8 that is consistent with the results of the observations of the about the Asian-Australian sector in [22; 24]. The different observations demonstrated the different effects of magnetic fields on ionosphere at different altitudes and different times. To confirm this feature of local time dependence for electron density to magnetic storms, the 2 h-averaged curves of TEC have been calculated at different latitudes for Swarm A and B in local day and nighttime, respectively. As shown in Figure 9a, around local daytime of 14:00 for Swarm A, the maximum occurred around the beginning of 26 August, corresponding to the minimum of SYM-H, as shown in Figure 1; while the minimum occurred at the end time of 26 August, and then during 27-31, the maxima of each day are larger than that on 24 August at the quiet time. At the local nighttime of 02:00 for Swarm A (Figure 9b), the maximum occurred at the main phase of this magnetic storm, and then there were big differences in different latitudes, where for a latitude of 45-60\({}^{\circ}\), the minimum occurred on 27 August, before all latitude curves slowly recovered to their normal state until Aug. 31. Compared with Swarm B in local daytime around 09:00 (Figure 9c), the big differences occurred during the recovery phase of 27-31, in which the maxima of 27-28 August did not go back to the normal level as it was at the beginning on 25 August; it was even lower from 29-31 August, which is not like the higher TEC in LT14:00 from 29-31 August, as shown in Figure 9a. In LT21:00 (Figure 9d), the lowest maximum was exhibited on 28 August at all low and middle latitudes, but on 29 August, it quickly recovered to the normal values, similar to those in 24-25 August. The daily minima from 24-31 August occurred on 29 August at LT09:00 or 21:00, typically at latitudes of 30-45\({}^{\circ}\) and 45-60\({}^{\circ}\). From these TEC curves, it can be found that the electron density has significant local time dependence with four kinds of variational trends corresponding to  
Figure 8: The global TEC mapping at local time 09:00 to 15:00 during 25–28 August in 2018 ((a)–(d) represents 25–28 August, respectively). four different local times either at the main phase or the recovery phase, and the magnetic storm affects all the trends at lower and middle latitudes. The nightside enhancement of TEC on 26 August in Figure 9d is similar to LT21 with those from Jason satellites in [25], and the TEC in latitudes of 15-30\({}^{\circ}\) even exceeded that of 0-15\({}^{\circ}\), which is totally different with that in Figure 9b at LT02 with almost no changes on 26 August, compared to those from 24-25 August. So the mid latitude enhancement of electron content in topside ionosphere can be further confirmed in the nightside at LT 21 from satellites of SWARM-B and Jason-2, three by our results and [25].