Natural Hazards and Earth System Sciences
2017
Earthquakes, Microelectromechanical systems, Sensitivity, Information sources, Cut-off, Ground stations, Waves, Evacuation systems, Media, Ground motion, Accelerometers, Risk, Data processing, Seismic activity, Shaking; Alarm systems, Seismic waves, Correlation, Failure, Tsunamis, Displacement, Ground-based observation, Mass media
One of the quickest means of tsunami evacuation is transfer to higher ground soon after strong and long ground shaking. Ground shaking itself is a good initiator of the evacuation from disastrous tsunami. Longer period seismic waves are considered to be more correlated with the earthquake magnitude. We investigated the possible application of this to tsunami hazard alarm using single-site ground motion observation. Information from the mass media is sometimes unavailable due to power failure soon after a large earthquake. Even when an official alarm is available, multiple information sources of tsunami alert would help people become aware of the coming risk of a tsunami. Thus, a device that indicates risk of a tsunami without requiring other data would be helpful to those who should evacuate. Since the sensitivity of a low-cost MEMS (microelectromechanical systems) accelerometer is sufficient for this purpose, tsunami alarm equipment for home use may be easily realized. Amplitude of long-period (20 s cutoff) displacement was proposed as the threshold for the alarm based on empirical relationships among magnitude, tsunami height, hypocentral distance, and peak ground displacement of seismic waves. Application of this method to recent major earthquakes indicated that such equipment could effectively alert people to the possibility of tsunami.
- Akio Katsumata, Yutaka Hayashi, Meteorological Research Institute, Japan Meteorological Agency, Nagamine 1-1, Tsukuba, Ibaraki Prefecture, Japan.
- Kazuki Miyaoka, Meteorological Research Institute, Japan Meteorological Agency, Nagamine 1-1, Tsukuba, Ibaraki Prefecture, Japan.
- Hiroaki Tsushima, Meteorological Research Institute, Japan Meteorological Agency, Nagamine 1-1, Tsukuba, Ibaraki Prefecture, Japan.
- Toshitaka Baba, Tokushima University, Shinkura-cho 2-24, Tokushima, Tokushima Prefecture, Japan.
- Patricio A. Catalán, Departamento de Obras Civiles, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso, Región de Valparaíso, Chile. Centro Nacional de Investigación para la Gestión Integrada de Desastres Naturales, CONICYT/FONDAP/1511007, Avenida Vicuña Mackenna 4860, Santiago, Región Metropolitana, Chile. Centro Científico Tecnológico de Valparaíso-CCTVal, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso, Región de Valparaíso, Chile.
- Cecilia Zelaya, Hydrographic and Oceanographic Service, Chilean Navy, Errázuriz Echaurren 254, Playa Ancha, Región Valparaíso, Chile.
- Felipe Riquelme Vasquez, National Office of Emergency of the Interior Ministry, Calle Beaucheff 1671, Santiago, Región Metropolitana, Chile.
- Rodrigo Sanchez-Olavarria, University of Chile, Av Libertador Bernardo O’Higgins 1058, Santiago, Región Metropolitana, Chile.
- Sergio Barrientos, University of Chile, Av Libertador Bernardo O’Higgins 1058, Santiago, Región Metropolitana, Chile.
