## 3 Automatic Detection Method  
An automatic detection method has been primarily developed into software to search and identify ionospheric variations when dealing with large amounts of plasma data measured by the DEMETER satellite since 2012 [20]. Investigations of the relationship between automatically searched ionospheric perturbations and strong earthquakes globally have been continuously conducted [21; 22; 23; 24; 25; 26; 27; 33; 34]. The software has been gradually improved from functional modules to an interface during this period to adjust to different data storage formats from DEMETER to the CSES. The interface primarily established in 2012 [20] has been currently updated for the ion data of the CSES, as shown Figure 1 (CSES Measured Ionospheric Perturbation Automatic Detection Software V1.0, authorized by National Copyright Administration of the People's Republic of China on 4 November 2024 under RN. 2024 SR1683021 in [[https://www.ccopyright.com.cn](https://www.ccopyright.com.cn)]([https://www.ccopyright.com.cn](https://www.ccopyright.com.cn)), accessed on 5 November 2024). Here, two variable parameters have to be specified before running the software: one is the latitude limit that usually is set to 90\({}^{\circ}\). The other is the peak time limit, which stands for the maximum value in minute of space scale of expected plasma perturbations and is generally specified as 2 min for the seismogenic ionospheric influence [27]. At the same time, the minimum value of the space scale of a perturbation keeps the same value as before and is set to 20 s to ensure that the perturbation has a certain duration to avoid pulse-like variations. An example has been given here in an effort to present the process of searching ionospheric perturbations using this software. The Level 2 ion density data along night orbit 21668 measured by CSES on 28 December 2021, as an input file has been processed by the software and the output results are only for the O\({}^{+}\) density. The final running interface can be seen in Figure 1. It is clear from Figure 1 that two O\({}^{+}\) perturbations (red dots) have been accepted along this orbit. Figure 2a presents the running night orbit 21668 (black dot line) in the map. The two blue dots stand for the same locations of searched perturbations in red shown in Figure 1, and the red dot is the Menyuan \(M_{\text{S}}\) 6.9 earthquake that occurred on 8 January 2022 in northwest China. The recorded O\({}^{+}\) density along this orbit during night time is shown in Figure 2b as a black line (Ion), and its smoothed data using the SAVGOL function are  
Figure 1: Interface of the automatic detection method software. The input file is CSES measured PAP data along night orbit 21668 and shown in left white framework. Two detected ionospheric perturbations were labelled by red dots in right world map. shown in red (Smo). Two O\({}^{+}\) perturbations complying with the set parameters in Figure 1 have been successfully searched from the smoothed line (red line in Figure 2b) and are labelled by P1 and P2 in Figure 2b. Their corresponding parameters are output in Table 1. From Figure 2a and Table 1, P1 appeared near the epicenter of the 8 January 2022, Menyuan \(M_{\text{S}}\) 6.9 earthquake with an enhanced magnitude of 30.1%, and it had been recognized as ionospheric precursor of this event, 11 days before and only 120 km away [24]. Another perturbation, P2, with a magnitude of 4.1% tended to be a background irregularity [27]. Automatically Searched Plasma Perturbations Before Several Aftershocks of the Wushi \(M_{\text{S}}\) 7.1 Earthquake  
An earthquake with magnitude \(M_{\text{S}}\) = 7.1 abruptly hit the Wushi area, Xinjiang province in northwest China at 02:09:05 CST (China Standard Time) on 23 January 2024, with an epicenter located at 41.20\({}^{\circ}\)N and 78.72\({}^{\circ}\)E and a depth of 22 km.