Estimation of tsunami characteristics under rough wind waves in the 2024 Noto Peninsula Earthquake

The tsunami that was triggered by the 2024 Noto Peninsula Earthquake caused severe inundation along the coast on the northeastern tip of the peninsula, propagated over the sea with rough wind waves, and reached the coast and rivers located away from the peninsula. This manuscript presents the results of a field survey and a supplementary analysis for investigating the tsunami characteristics away from the peninsula where rough wind waves had a significant influence on the tsunami behavior. Video images captured by closed-circuit television (CCTV) cameras were used for onsite detection of the tsunami traces and for extracting time-varying water level profiles. Wind waves had little influence on the tsunamis along the lower reaches of the rivers, and the measured tsunami heights were consistent with each other in the nearby field. At most of the survey sites, the highest tsunami traces were created not by the first but by the following tsunami. Along Toyama Bay, the tsunami water levels first decreased within several minutes after the earthquake, and the arrival times for this negative tsunami peak was earlier in the southern part of the bay. These characteristics may indicate the existence of multiple tsunami sources inside Toyama Bay.