Japanese experts back real-time earthquake warning system

TOKYO – Japanese experts have stressed the importance of a well-coordinated, real-time public information system in saving thousands of lives in the event of a major earthquake, such as the one that may be brought about by a movement of the West Valley Fault traversing Metro Manila.

Kenji Satake, a professor at the Earthquake Research Institute at the University of Tokyo, told foreign journalists here on Tuesday that thousands of lives were spared during the magnitude 9 earthquake in March 2011 as they were immediately advised of an impending tsunami.

Satake recalled that an initial public advisory for a tsunami was issued by the Japan Meteorological Agency (JMA) within three minutes after the earthquake struck off the coast of eastern Japan.

Earlier this year, the Philippine Institute for Volcanology and Seismology (Phivolcs) said it plans to adopt a public information system similar to the one currently in place in Japan, which involves a well-coordinated system of sending information to the public and relevant government agencies.

Phivolcs director Renato Solidum told the Philippine News Agency that they plan to put up a communication warning system involving the use of digital television, which is similar to that of Japan.

Tomoaki Ozaki of the JMA earthquake and tsunami observation division said their system requires them to pass on earthquake information immediately to the public through private and government-controlled media, as well as through telecommunications companies.

Ozaki said they have continued to improve their warning system to further mitigate the damage and loss of lives caused by earthquakes.

Around 18,000 people died in the disaster, called the Great East Japan Earthquake Disaster, due to the underestimated earthquake size and tsunami height.

Early warning system

According to JMA, Japan now has 290 seismic stations and another 4,357 intensity stations to monitor the occurrence of earthquakes across the country.

Ozaki said the stations enable them to provide an earthquake early warning (EEW), a system that calculates the epicenter of the tremor and its magnitude based on the primary wave data collected.

The EEW can provide an estimate of the following ground shaking caused by a secondary wave seconds before it actually hits areas that will be affected.

Satake said that while the EEW can only provide a short lead time before the strong ground tremor occurs – usually only a matter of seconds – this could mean the difference between life and death of people in dangerous locations.