## 4 Discussion
[68] studied the occurrence of very high Swarm-measured \(T_{\rm e}\) values (\(T_{\rm e,measured}\geq 6000\) K), and corresponding spatial, diurnal, and seasonal varia  
Figure 9: Conditioned probability density function of \(T_{\rm e}\) values measured by Swarm satellites (left panels), and after applying the [PERSON] et al. [24] correction (right panels), at fixed IRI-modeled \(T_{\rm e}\) values. From top to bottom, the analysis refers to Swarm A, B, and C. The black circles refer to the median values of measured and corrected Swarm \(T_{\rm e}\) at fixed IRI-modeled \(T_{\rm e}\) values. Error bars are the median absolute deviation. The magenta lines are linear regression fits for IRI \(T_{\rm e}\) below 2200 K, with corresponding parameters shown in the lower right boxes. tions. As expected, very high \(T_{\rm e}\) values were recorded above all at high latitudes but with well-defined trends. Specifically, the occurrence of very high \(T_{\rm e,measured}\) values maximizes in winter and is minimum in summer, with intermediate values at both equinoxes. Moreover, the occurrence is asymmetric between hemispheres, being highest in the Southern hemisphere, where it can reach 40% of the total observations in winter. These extremely high \(T_{\rm e}\) values are not represented at all by IRI, which is limited to values below about 4300 K (see Figures 2 and 9). As a consequence, the departure from the linear dependence between \(T_{\rm e,measured}\) and \(T_{\rm e,modeled}\) for the highest values cannot be related to the application of the Lomidze correction. The fact that the occurrence of \(T_{\rm e,measured}\geq 6000\) K values is quite remarkable at high latitudes and that it usually happens at small spatial and temporal scales [68] drives us to the conclusion that the median climatological representation given by the IRI model cannot properly represent such very fast and steep \(T_{\rm e}\) variations. This is mainly due to the limited spatial (20 degrees in invdip latitude) and temporal (80 minutes in MLT) resolution of its current spherical harmonic expansion approach [26]. Nevertheless, we point out that the Lomidze correction is based on a dataset of \(T_{\rm e}\) measurements from Arecibo, Jicamarca, and Millstone Hill ISRs, which are all low- and mid-latitude stations. This means that no high-latitude measurement was considered and, most importantly, only values in the range \(T_{\rm e,measured}<3500\) K (in HG mode) were used to derive the calibration curves (see Figure 7 in [24]). With regard to this, it would be of great benefit to include high-latitude ISR stations (e.g., Resolute Bay (74.7\({}^{\circ}\)N, 94.9\({}^{\circ}\)W), Poker Flat (65.1\({}^{\circ}\)N, 147.5\({}^{\circ}\)W), Irkutsk (52.9\({}^{\circ}\)N, 103.3\({}^{\circ}\)E), EISCAT Tromse (69.3\({}^{\circ}\)N, 19.1\({}^{\circ}\)E), EISCAT Kiruna (67.5\({}^{\circ}\)N, 20.3\({}^{\circ}\)E), EISCAT Sodankyla (67.2\({}^{\circ}\)N, 26.4\({}^{\circ}\)E), EISCAT Longyearbyen (78.1\({}^{\circ}\)N, 16.0\({}^{\circ}\)E)) in the Lomidze dataset to also characterize the high \(T_{\rm e}\) values usually recorded at auroral latitudes. Finally, the possible overestimation of \(T_{\rm e}\) values measured by Swarm LPs due to instrumental/environmental effects cannot be completely ignored. This is why, a more in-depth analysis, based on different datasets and measurement techniques, is needed to clarify the origin and reliability of the very high \(T_{\rm e}\) values recorded by Swarm satellites.