[U-15] The 2024 Noto Peninsula Earthquake (1:J)

[U15-P79] Infrasound Network Analysis of Nationwide Pressure Fluctuations Observed after the 2024 Noto Peninsula Earthquake and Estimation of Tsunami Magnitude

*Yasuhiro Nishikawa¹, Masa-yuki Yamamoto¹, Kensuke Nakajima², Yoshihiro Kakinami³, Hiroaki Saito⁴, Makiko Iwakuni⁵, Masashi Motohashi⁵, Ryouichi Nishimura⁶, Yoshiyuki Tanaka⁷, Hiromu Sakaue⁷, Tatsuki Washimi⁸, Yoshiaki Tamura⁸, Takaaki Yokozawa⁹, Emi Imada², Takuma Oi¹⁰, Ayami Suzuki¹⁰, Ryohei Oi¹⁰, Sota Nakajo¹¹ (1.Kochi University of technology. School of System Engineering., 2.Department of Earth and Planetary Sciences,Flculty of Sciences,Kyushu University, 3.Hokkaido Information University, 4.Department of Information Systems in Business, Hakodate Otani College, 5.JAPAN WEATHER ASSOCIATION, 6.National Institute of Information and Communications Technology, 7.Earth and Planetary Science, The University of Tokyo, 8.National Astronomical Observatory of Japan, Mizusawa VLBI Observatory, 9.Institute for Cosmic Ray Research, The University of Tokyo, 10. Krone Corporation, 11.Osaka Metropolitan University)

Keywords:Infrasound, Tsunami

Infrasound Network Analysis of Nationwide Pressure Fluctuations Observed after the 2024 Noto Peninsula Earthquake and Estimation of Tsunami Magnitude

The M7.6 earthquake that occurred the Noto Peninsula at 16:10 on January 1, 2024, recorded a maximum intensity of 7, followed immediately by a tsunami. This tsunami potentially induced atmospheric pressure fluctuations, which were observed across Japan soon after. These fluctuations comprised various pressure wave types, including Lamb waves and atmospheric diffraction waves, detected by multiple infrasound sensors.

Drawing from past experience (Arai et al., 2011), after the 2011 Tohoku earthquake off the Pacific coast, many infrasound sensors were deployed throughout Japan, particularly along the Pacific Ocean side, to capture pressure fluctuations caused by tsunamis. These sensors were similarly employed during the recent 2024 Noto Peninsula earthquake to observe data on nationwide atmospheric pressure fluctuations. Given the influence of tsunami source and upper atmosphere conditions on these pressure waves, thorough analysis with multiple-site infrasound data and model calculation of infrasonic wave propagation is important.

In this presentation, we will analyze the infrasound data observed nationwide and provide an estimation of tsunami magnitude based on waveform analysis and data characteristics. Furthermore, we will discuss the role and utility of the Infrasound observation network.