# Ionospheric Weather at Two Starlink Launches during Two-Phase Geomagnetic Storms
## 3 Conclusions  
The GIM-TEC global ionospheric maps of the total electron content have been used to produce the ionospheric weather GIM-W index maps and Global Electron Content (\(GEC\)). GIM-TEC maps are available with a lag (delay) of 1-2 days (real-time GIMs have a lag of less than 15 min), so the GIMs forecast is required by the time of the launch of satellites. We observed a \(GEC\) increment from 10 to 24% for the storm peak after the Starlink launch at both storms, accompanying the neutral density increase. This characteristic presents a measure of the positive \(GEC\) intensification for the second phase of the ionosphere storm. The different 1- and 2-days 'forecast' of GIMs produced by IZMIRAN, CODE, CASG and BUAG centers is compared with 'true' \(GEC\) profiles during two geomagnetic storms on 3-5 February and 7-9 July 2022 when S-36 and S-49 Starlink satellites have been launched at storm time. The NN UPC-ionSAT forecast for 6, 12, 18, 24 and 48 h in advance has been also evaluated for these events. A numerical estimate of performance of forecasts is made with R-square (\(R^{2}\)) and \(RMS\) formulae. The monthly estimates of \(R^{2}\) for February and July 2022 reveal either the acceptable conformity or the difference between the 'true' and 'forecast' GIMs transformed to Global Electron Content metrics. However, a similar estimate for the storm conditions on 3-5 February and 7-9 July 2022 disclosed a failure to reasonably forecast \(GEC\) (and GIMs). While the positive \(R^{2}\) = 1 presents the best conformity of the data we obtained, the negative \(R^{2}\) for all forecasting results during the storms which characterize unreliable storm-time performance of the forecasting techniques under consideration. The RMS deviations during the storm are greater than those obtained for the total month of February and of July, where the storm conditions are mixed with the dominant quiet times. The predicted GIMs providing closer forecasted \(GEC\) (and detrended \(GEC\)) to the now-casted ones are those with horizons at 24 (and 48) h, and from the day after the storm, i.e., once the now-casted GIMs have experienced the starting of the space weather event. The results of this study aim to revisit the GIM prediction, from the \(GEC\) perspective, for understanding, firstly, and improving, afterwards, the corresponding forecasting, specially at the subdaily horizons. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \(X\) & **6 h** & **12 h** & **18 h** & **24 h** & **48 h** \\ \hline \(\gamma\) & \multicolumn{6}{c}{**3–5 February 2022**} \\ \hline \multirow{2}{*}{UQRG} & \(-1.18\) & \(-2.53\) & \(-1.68\) & \(-2.71\) & \(-1.52\) & \(R^{2}\) \\  & 0.149 & 0.190 & 0.166 & 0.195 & 0.160 & \(RMS\) \\ \hline \multirow{2}{*}{UADG} & \(-0.39\) & \(-0.75\) & \(-0.67\) & \(-1.107\) & \(-43.8\) & \(R^{2}\) \\  & 0.201 & 0.225 & 0.220 & 0.248 & 1.142 & \(RMS\) \\ \hline \multirow{2}{*}{UQRG} & \(-0.17\) & \(-0.32\) & \(-0.71\) & \(-3.60\) & \(-2.40\) & \(R^{2}\) \\  & 0.086 & 0.092 & 0.104 & 0.170 & 0.147 & \(RMS\) \\ \hline \multirow{2}{*}{UADG} & \(-0.19\) & \(-0.29\) & \(-0.72\) & \(-3.95\) & \(-2.38\) & \(R^{2}\) \\  & 0.081 & 0.084 & 0.097 & 0.164 & 0.136 & \(RMS\) \\ \hline \hline \end{tabular}
\end{table} 
Table 5: \(R^{2}\) and \(RMS\) deviations between UQRG and UADG data and NN forecast for 6, 12, 18, 24 and 48 h in advance during geomagnetic storms on 3–5 February and 7–8 July 2022 starting from the day of the Starlink launches. Variabilities of the Earth's ionosphere during the storms can adversely affect the space-based technological infrastructures, such as Low-Earth Orbit (LEO) satellites including the Starlink network and the Global Navigation Satellite System (GNSS). In turn, the GNSS observations and GIMs products provide a ground for the development of reliable GIMs forecasting techniques, which presents a challenge for the satellites' operation during the space weather events. Conceptualization, T.G., M.H.-P. and I.S. ; data curation, T.G. and M.H.-P.; investigation, T.G., M.H.-P. and I.S.