Research on improvement of precision for seismic intensity prediction in Earthquake Early Warnings

JMA’s Earthquake Early Warning (EEW) system is operated across Japan to mitigate the effects of earthquake disasters by giving people more time to take appropriate safety measures in advance of strong seismic shaking. Based on this technology, seismic intensity is predicted and warnings are very quickly issued to people before strong shaking starts when the scale of shaking is predictedto exceed a certain level.

This research project involves the investigation of a new and innovative technique to improve the timeliness and recision of EEWs based on real-time observation of incoming seismic ground motion. The new method will address the technical weaknesses associated with large extent of source rupture and multiple simultaneous events as experienced during the M9.0 Tohoku Earthquake and its aftershocks.

Recently, consideration of long-period seismic waves becomes increasingly important as well as seismic intensity as more and more buildings with over 20 floors are constructed in urban areas of Japan. This project supports the expansion of the EEW technique for application to seismic waves with various periods.

Prediction of seismic intensity based on real-time observation of incoming seismic ground motion. The prediction model is constantly revised using the real-time observation.