## 1 Introduction
The characterization of these ionosphere vertical structure disturbances provides a new approach for the seismo-ionosphere coupling mechanism. Many studies have shown that the ionosphere anomaly is caused by the release of large amounts of energy from the earth's crust into the ionosphere. By RO vertical disturbance, the energy propagation from the epicenter to the ionosphere may be traced [17]. The recorded path is conducive to capturing potential excitation and coupling channels, such as AGWs released from seismogenic areas [18]. As the most successful occultation plan by far, the main goal of the joint Taiwan-United States FORMOSAT-3/COSMIC occultation is to prove the research possibility of the atmospheric structure and motion in the form of the satellite constellation. After successful networking in 2006, the initial generation of FORMOSAT-3/COSMIC comprised six satellite constellations, distributed at an altitude of 800 km. The system provides about 2000-2500 COSMIC occultation profiles per day at its peak [19]. Based on these profiles, ionospheric hierarchy detection and vertical disturbance characteristics are studied with the help of abundant electronic density profiles. However, since 2011, with some satellite functional degradation,the number of occultation profiles has decreased below 1000. The US Air Force Space Test Program successfully launched six FORMOSAT-7/COSMIC-2 satellites into a 24 deg inclination earth orbit on 25 June 2019. Because of the recent completion of data calibration and validation, the COSMIC generation-2 system now has massive data--more than the initial generation of products. The enhanced performance has potential for the ionospheric coupling mechanism and the detection of abnormal effects [20]. At 6:34 GMT, 27 February 2010, a shallow devastating quake with a magnitude of 8.8 on the Richter scale hit near Concepcion, Chile. The earthquake's focal depth was only 55 km, and the epicenter was in the waters near Maule, 320 km southwest of Santiago, Chile. This event is a typical thrust plate event. Nazca Plate, located in the west of the earthquake area, subducted rapidly to the South American plate at a compression rate of 65 mm/yr. The action resulted in the gradual accumulation of interplate stress until surface fracture [21]. After the earthquakes, the city moved 3 m westward. In 2010, the COSMIC system could stably provide \(\sim\)1500 detection profiles every day. Rich profile data provides a possibility for the vertical structure detection of the seismo-ionosphere effect [22]. Employing a case study of the Mw 8.8 Concepcion earthquake on 27 February 2010, the COSMIC occultation observation system's ability to monitor the ionosphere disturbance was studied. Based on statistical analysis, the background variation's effectiveness is verified, and a strict anomaly condition is given. After that, two aspects of the ionospheric anomalies in the F2 layer and other heights were investigated successively. On the one hand, by comparing the observed value with the constructed global Nmf2 map (GNM), the abnormal Nmf2 point fields over the detected area (10\({}^{\circ}\)E-130\({}^{\circ}\)E, 10\({}^{\circ}\)N-60\({}^{\circ}\)S) were detected. On the other hand, by observing the electron density profiles with a large deviation, the ionosphere fluctuation and anomalies in different heights were analyzed. This research, we believe, has practical and referential significance for the measurement model of the ionosphere and climate variations when FORMOSAT-7/COSMIC-2 is fully operational in the future.