ESTIMATION OF TYPHOON-GENERATED HIGH WAVES BY SECONDARY MICROSEISMS OBSERVED BY F-NET

Abstract

 Ocean waves excite microseisms. There is a potential to estimate typhoon-generated high waves, which are difficult to observe, from continuous seismic observation. We estimated typhoon-generated high waves using the relationship between typhoon-generated high waves and secondary microseisms in F-net Abuyama station. We analyzed statistically observed seismic waves by F-net, ocean wave observation by NOWPHAS, and ocean wave hindcasting data by WAVEWATCH III in summer season and assessed the relationship between microseisms and typhoon-generated high waves. The correlation between the observational significant wave height and secondary microseisms energy is more than 0.7. The correlation between 0.1Hz-0.15Hz secondary microseisms energy and simulated significant wave height is high and typhoon-generated high waves have a high correlation with low frequency microseisms energy. We constructed a statistical model that can assess typhoon-generated high waves from secondary microseisms and estimated ocean wave height when the typhoon is close to Japan.