[M-IS08] Interdisciplinary studies on pre-earthquake processes

[MIS08-07] Seismo-ionospheric anomalies before the 11 March 2011 M9.0 Tohoku Earthquake

*Jann-Yenq LIU^1,2,3, FU-YUAN CHANG¹, I-Te Lee⁴, Katsumi Hattori⁵, Yuh-Ing Chen⁶ (1.Center for Astronautical Physics and Engineering, National Central University, Taoyuan, TAIWAN, 2.Department of Space Science and Engineering, National Central University, TAIWAN, 3.Center for Space and Remote Sensing Research, National Central University, Taoyuan, TAIWAN, 4.Center Weather Bureau, Taipei, TAIWAN, 5.Department of Earth Sciences, Graduate School of Science, Chiba University, Chiba, JAPAN, 6.Institute of Statistics, National Central University, Taoyuan, TAIWAN)

Keywords:Tohoku Earthquake, GIM TEC, FORMOSAT-3/COSMIC, ionospheric earthquake precursor, TIEGCM, seismo-electric field

In this paper, observations of the total electron content (TEC) of the global ionosphere map (GIM), radio occultation electron density profiles of FORMOSAT-3/COSMIC, and in situ plasma quantities probed by DMSP satellite are used to study seismo-ionospheric anomalies associated the 11 March 2011 M9.0 Tohoku earthquake, while the Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) is applied to simulate and understand the observed anomalies. The observation shows that the GIM TEC over the epicenter significantly and continuously enhances on 6-8 March 2011, 4-2 days before the earthquake. The spatial analysis further demonstrates that the enhancement anomaly specifically and persistently appears in the northern epicenter area. Simulation results well agree with the observations, which suggest that the electric potential around the epicenter has been distorted and significantly affects the TEC during the earthquake preparation period.