[M-IS04] Interdisciplinary studies on pre-earthquake processes

[MIS04-07] Seismo-Ionospheric precursors of the 1 January 2024 Noto M7.6 Earthquake

*Jann-Yenq LIU¹, Katsumi HATTORI², Chi-Yen LIN³, Yun-Cheng WEN⁴, Fu-Yuan CHANG³, Yuh-Ing CHEN⁵ (1.Center for Astronautical Physics and Engineering, Department of Space Science and Engineering, Center for Space and Remote Sensing Research, National Central University, 2.Center for Environmental Remote Sensing, Department of Earth Sciences, Graduate School of Science, Research Institute of Disaster Medicine, Chiba University, 3.Center for Astronautical Physics and Engineering, Department of Space Science and Engineering, National Central University, 4.Department of Space Science and Engineering, National Central University, 5.Graduate Institute of Statistics, National Central University)

Keywords:2024 Noto M7.6 Earthquake, global ionosphere map, total electron content, FORMOSAT-5/AIP, seismo-ionospheric precursor

On 1 January 2024 at 07:10 UT (universal time), a magnitude M7.6 earthquake struck the Noto Peninsula in Ishikawa Prefecture, Japan. The total electron content (TEC) of GIM (global ionosphere map) is used to study the temporal variation and spatial distribution of seismo-ionospheric anomalies of the earthquake, while the FORMOSAT-5/AIP (advanced ionospheric probe) ion velocity is used to explore possible causal mechanisms of the observed seismo-ionospheric precursors (SIPs). The spatial analyses of GIM TECs revel that negative and positive SIPs appear around the epicenter on day 33-35, 13, 7-8 and 30 before the Noto M7.6 earthquake, respectively. These generally agree with the polarities and lead-days of SIPs associated with large earthquakes in Japan during 1999-2023. The global ionosphere specification is employed to study the three-dimensional structure of electron density and electrodynamics. FORMOSAT-5/AIP ion velocities show that the observed SIPs are caused by 0.13-0.74 mV/m eastward over the epicenter during the four day-periods.