Evaluation of microseismic motion at the KAGRA site based on ocean wave data

TL;DR

This paper investigates how ocean wave data correlates with microseismic ground vibrations at the KAGRA gravitational wave detector site, aiming to improve understanding and forecasting of seismic noise.

Contribution

It analyzes seasonal variations and correlations of ocean waves across Japan and links these to microseismic motion at KAGRA, demonstrating a method for microseismic forecasting.

Findings

Ocean wave data explains microseismic motion at KAGRA using principal components.

Seasonal variations significantly affect ocean wave heights and microseismic activity.

A potential application in microseismic forecasting is demonstrated.

Abstract

The microseismic motion, ambient ground vibration caused by ocean waves, affects ground-based gravitational wave detectors. In this study, characteristics of the ocean waves including seasonal variations and correlation coefficients were investigated for the significant wave heights at 13 coasts in Japan. The relationship between the ocean waves and the microseismic motion at the KAGRA site was also evaluated. As a result, it almost succeeded in explaining the microseismic motion at the KAGRA site by the principal components of the ocean wave data. One possible application of this study is microseismic forecasting, an example of which is also presented.