## 3 Results
### Swarm Magnetic Field Results  
In this section, we applied the WSC algorithm to the _Swarm_ magnetic field data recorded by the three main satellites of the constellation from 26 November 2013 until 25 November 2021, i.e., the first 8 years of available data. Figure 1 represents the WSC applied to the _Swarm_ Y-East component magnetic field anomalies with M5.5+ earthquakes in a time window of 120 days (i.e., 90 days before each earthquake and 30 after for methods  
Figure 1: Correlation of _Swarm_ magnetic field anomalies with M5.5+ earthquakes using four different methods: (**A**) all anomalies are associated with all compatible earthquakes; (**B**) each anomaly is associated with the closest earthquake in space and time, i.e., the minimum of log(\(\Delta\)T R); (**C**) the anomaly is associated with the greatest magnitude earthquake; (**D**) the anomaly is associated with the earthquake closer to the Kikitake law, with coefficients from [PERSON] et al. [29]. The graphs are cut for the vertical section without significant information, showing only the closer band to the earthquake epicenter. The color bar represents the density of anomalies in terms of the number of anomalies per square degree. 1, 2, and 3, and 120 days before each earthquake for method 4) using the four methods to select which earthquake is associated with the anomaly in case of ambiguity. We note that all the methods identify the same group of anomalies from around \(-\)40 to \(-\)10 days, and, in some of them, it is also the absolute maximum concentration. It is very interesting that, even with Method 2, which minimizes the log (\(\Delta\)T R), the absolute maximum concentration is 12 days prior to the earthquake and not the co-seismic, as the method would forcefully enhance the anomalies closer to the event (actually, it is only this method that presents a significant concentration at the earthquake occurrence, although it is not the largest one). Figure S2 (in Supplementary Materials) reports the statistical correlation analysis for the _Swarm_ Y-East magnetic field component anomalies (extracted with a threshold \(k_{t}\) = 2.5) with M5.5+ earthquakes from 500 days before until 500 days after each event using Method 1. With these criteria, we can obtain symmetric analyzed time and see that the maximum concentration of anomalies preceded the earthquake (of about 30 \(\pm\) 10 days). Furthermore, the concentration of anomalies before the earthquake is slightly higher than that after the event. The total number of anomalies in the first row (i.e., the closest to the epicenter) before the earthquake is 16,630, while the total number after the earthquake is 16,436, showing that, before the earthquake, there are 194 more anomalies than the ones after it. Even if this number is just 1.2% more, it could support the idea that, inside the identified anomalies, there could be a part likely produced by ionospheric seismo-induced phenomena. A specific discussion that took into account the geomagnetic quiet and disturbed amount of time before and after each event is reported in Section 4.5, and the specific difference seems to be influenced by this aspect. To search for a possible relationship between the anticipation time and magnitude of the earthquakes, the events have been divided into five magnitude bands (the same used in Figure 5 of [PERSON] et al. [30]): 5.5 \(\leq\) M \(\leq\) 5.9, 6.0 \(\leq\) M \(\leq\) 6.4, 6.5 \(\leq\) M \(\leq\) 6.9, 7.0 \(\leq\) M \(\leq\) 7.4, and M \(\geq\) 7.5 using Method 1. Figure 2 represents the WSC applied to 8 years of _Swarm_ magnetic field anomalies and earthquakes divided into magnitude bands. Here, an extended period before the earthquake (1000 days instead of 500, as in [29]) is used, as now the statistics are better supported by a larger amount of data. It is worth noting that, in these analyses, a part of the events is not fully analyzed. In particular, the earthquakes that occur in the first 1000 days of the analyzed years have an incomplete time window before them.