Seismological forecasting: prospects within the International Decade for Natural Disaster Reduction

R.L. Kintanar¹

¹R.L. Kintanar is Chairman, International Decade for Natural Disaster Reduction, Manila, Philippines.

The United Nations International Decade for Disaster Reduction (IDNDR) officially started on 1 January 1990. The Scientific and Technical Committee which I now chair determines the policy and programme of the IDNDR but the bulk of its activities and projects are regional or national in nature.

The Philippines lies in the same Pacific ring of fire as Japan and is also affected by many of the same hazards that affect Japan. Among these are earthquakes, volcanic eruptions, typhoons, floods, droughts, wildfires and landslides. I had the personal experience of conducting a technical survey of the damage from the earthquake in Lamao on the island of Mindanao on 1 April 1955. Those who witnessed the effects of the Kobe earthquake will agree with me that such an episode leaves a permanent impression and is an experience never to be forgotten.

Project RADIUS

At the beginning of the IDNDR it seemed difficult to comprehend the international dimension of disaster preparedness and to change attitudes and counter the lack of interest. Time and the increasing impact of natural disasters in a fast-developing world have made their impact on more and more of the national leaderships and on the people themselves. The IDNDR secretariat launched the RADIUS project in 1996 to realize the concept of the IDNDR and the Yokohama Strategy and Plan of Action that was developed in 1994.

The RADIUS project aims to promote worldwide activities for the reduction of seismic disasters in urban areas, particularly in developing countries, so that the countries of the world will be able to face the new millennium with greater security against natural disasters. The project will develop common methodologies and collect state-of-the-art technologies for seismic risk assessment in urban areas in order to raise public awareness and provide direction for disaster mitigation. It is expected that many of these technologies will come from among those developed and used in Japan.

Personal earthquake drills

Earthquake drills have been very useful in informing large numbers of the population on the proper action to be taken in the few seconds after the onset of a strong tremor. The correct reaction to a strong tremor may make the difference between major or minor injuries to the person concerned.

The main problem with earthquake drills is the large amount of work required to organize, prepare and implement them. Anyone who has had a hand in organizing such a drill, or who has been involved as a participant, knows why these drills cannot be widely utilized.

In an urban centre like Manila, large-scale earthquake drills are next to impossible and no drills of wide application have been attempted. In the early 1970s, after a few very strong earthquakes affected Manila, we tried to institutionalize earthquake drills. The best we could do was to propose an alternative - the personal earthquake drill. The government undertook an information campaign to make available to as many of the population as possible the various simple pieces of advice for personal reaction in case of an earthquake.

In the personal earthquake drill we stress the importance of personal reactions. We ask people to identify where they spend the greater amount of their time. We then ask them to imagine a strong tremor and to clarify the appropriate reaction they should have considering their location when the earthquake occurs. We ask them to repeat this procedure for their own security every few weeks or so. We explain that this mental exercise need take only a few minutes. We also suggest that the exercise could be usefully repeated each time they find themselves in a new situation, such as in a movie-house or restaurant or department store.

It is difficult to assess the effectiveness of this mental earthquake drill, but even if it serves only to remind people of the risk around them it may well be worth the few minutes of mental exercise.

Forecasting and warning

Even short-term forecasts of the time of an earthquake's occurrence, its magnitude and the area of its impact need a lot more study and intensified research. Only very few examples of reasonably successful predictions have been known, as for example in China, France, and the Caribbean and Mediterranean areas. Studies have identified the Pacific as the area most susceptible to earthquakes. Furthermore, areas of inner-plate seismic faults have been identified, which can be the focus of scientific studies and research. Several precursors of earthquakes have been identified, but these cannot as yet be easily used as predictors. Detailed analysis of seismographic measurements (e.g. by advanced pattern-recognition technology) and observations of animal behaviour are among these. Another promising tool for earthquake forecasting is the measurement of the wave velocity in the ground which is known to change drastically before an earthquake occurs. Monitoring of the velocity of these waves is currently being undertaken in four areas of the world.

Looking to the future

It is now time to consolidate all activities for natural disaster reduction. The multisectoral components of this symposium will certainly help in this endeavour. The United Nations efforts embodied in the IDNDR will formally terminate on 31 December 1999. When that time comes we hope that the national, regional and international leadership in disaster reduction that has developed during the decade will continue to prosper.