tokyo

Earthquake research in Japan should focus on understanding the mechanism of earthquakes, rather than predicting them, according to an advisory body to the Japanese prime minister. This shift is needed to develop new disaster prevention technologies.

The research plan was released last week by the Headquarters for Earthquake Research Promotion (HERP). It is intended to shape Japan's earthquake research for the next decade, and will influence projects at national research institutes from April, when the 1999 fiscal year begins.

There is a growing perception in Japan that successful earthquake prediction may not be realistic. Last year, the Geodetic Council, which advises the Ministry of Education, Science, Sports and Culture, made the first changes in its 30-year-old programme of attempting to predict imminent earthquakes, shifting its focus to long-term forecasts of areas likely to be struck by major tremors (see Nature 393, 202; 1998).

HERP's plan goes further by promoting research and development in disaster prevention techniques independent of earthquake prediction, and by emphasizing basic research on earthquake processes through satellite observation, for example with the global positioning systems.

Set up in 1995 after the Kobe earthquake to promote collaboration between ministries, universities and research institutes, HERP sees the main aim of its plan as exploring ways to minimize the effects of major earthquakes. It seeks to do this by analysis and simulation of seismic ground motions, and by creating a system to gather real-time seismic data.

While the plan emphasizes some earthquake prediction research, such as studies of the geophysical and geostructural features of seismogenic zones, it calls for a departure from techniques based on data collection. It states that accurately predicting the timing of earthquakes is “exceptionally difficult” with current technology.

“Although the prediction programme has shifted its focus to making long-term forecasts, there is still no guarantee that this is actually possible,” says Mitsuhiro Matsuura, professor in seismology at Tokyo University. “The purpose of earthquake research is not to make a guess when an earthquake will strike, but to understand the scientific mechanism behind it.”

The plan also calls for a new data centre to collect and analyse information related to domestic earthquake research. While its prime objective would be to provide information to researchers, it would also be accessible to the public.

By opening up this information, HERP hopes to give a better view of present research, and to prevent the exploitation of funds in the name of earthquake research, which is often generously funded and is said to be more likely to escape critical review.

But many researchers are concerned that disclosing data could mislead the public. “The disclosure of research data would certainly be beneficial to those involved in earthquake research, but it could cause misunderstanding among the public,” warns Robert Geller, a seismologist at Tokyo University. “For example, the long-term absence of an earthquake in a particular region could give the residents a false sense of security.”

The physics of earthquake processes, especially their dynamics, still requires detailed research, says Matsuura. Therefore the public must be given a careful explanation of seismological phenomena so people understand what happens.