A Study on the 2016 Kumamoto Earthquake: Citizen’s Evaluation of Earthquake Information and Their Evacuation and Sheltering Behaviors
Reo Kimura*,†, Shoji Ohtomo**, and Naoshi Hirata***
*School of Human Science and Environment, University of Hyogo
1-1-12 Shinzaike-honcho, Himeji, Hyogo 670-0092, Japan
**Faculty of Human Sciences, Konan Women’s University, Kobe, Japan
***Earthquake Research Institute, the University of Tokyo, Tokyo, Japan
In order to reveal the current status and issues of the victims of the 2016 Kumamoto Earthquake eight months after its occurrence, we conducted large-scale random sample questionnaire surveys with victims aged 18 and over in the most affected municipalities from November to December 2016. We decided to sample a total of 7,000 victims (1,600 from Kumamoto City and 5,400 from the other thirteen municipalities) with an expected collection rate of 25% and a sampling error of 5%; 3,272 victims effectively responded to the questionnaires (effective collection rate: 46.7%). The Kumamoto Earthquake was a series of earthquakes including foreshocks and main shocks of magnitude 7 on the Japanese seismic intensity scale, and aftershocks that appear to have significantly influenced the victims’ response behaviors as well as the recovery and reconstruction of the affected areas.
The questionnaire survey on whether the victims’ pre-earthquake knowledge and awareness had any influence on their post-earthquake behaviors reveals that not more than 30% were aware of the active faults present in their areas before the earthquake occurred and that half of them hoped that no earthquakes would occur. On the other hand, the victims who were aware of the active faults present in their areas and who were afraid that an earthquake could occur within 10 years had planned accordingly and had stocked the necessary goods and provisions.
The questionnaire survey on how the victims behaved in the event of the foreshocks and main shocks reveals that about half of them evacuated and found shelter after the foreshocks. Those who feared any aftershocks, and the damage to their buildings due to the aftershocks, evacuated and took shelter. Those whose buildings were not damaged and whose lifelines were available did not evacuate or take shelter. After the main shock, about 70% of the victims evacuated and took shelter because, in addition to their fears of the aftershocks, their buildings were actually damaged and their lifelines had been rendered unavailable.
The questionnaire survey on whether the victims’ pre-earthquake knowledge and awareness had any influence on their post-earthquake behaviors reveals that in the event of an earthquake, like in the case of the foreshocks of the Kumamoto Earthquake in which human beings and buildings were not so scathed and people could not decide whether to evacuate or take shelter, those with more pre-earthquake knowledge and with awareness of earthquake damage better anticipated the aftershock occurrences. On the other hand, in the event of the main shocks of the Kumamoto Earthquake, in which there was great damage to humans and buildings, people with or without pre-earthquake knowledge and awareness on earthquake damage were urged to evacuate and take shelter.
The questionnaire survey on whether aftershock information was properly communicated to the victims reveals that they followed the information on aftershocks broadcast by TVs and radios immediately after the foreshock had occurred. The victims did not follow the Meteorological Agency’s press release on the aftershocks on the afternoon of the following day in order to get an update. Instead, they took the information broadcast by TVs and radios as “no great aftershocks would occur in the future,” which was completely different from what the Meteorological Agency’s press release intended. The questionnaire survey on the influences of the aftershock information on the victims’ evacuation and sheltering behaviors reveals that the Meteorological Agency’s press release on the following day of the foreshock occurrence stated that the probability of the aftershock occurrence of lower 6 or over on the Japanese seismic intensity scale is 20% in the following three days, and that of the aftershock occurrence of upper 5 or over on the Japanese seismic intensity scale is 40%. This seems to have had a greater influence on the behaviors of the victims who assumed that “no great aftershocks would occur in the future” as compared to the behaviors of those who assumed that “an aftershock could occur anytime in the future” and “a big aftershock might occur in the future.”
With regard to the movements in the victims’ long-term post-earthquake residences and evacuation destinations, 57.5% of the total victims stayed at home after the foreshock occurrence, which is not so different from the case of the Hanshin-Awaji (Kobe) Earthquake, an inland earthquake with relatively few aftershock activities. However, the ratio of the victims who stayed at home stood at 28.7% after the main shock occurrence, at 32.8% on the first weekend or about four days after the foreshock occurrence, and at 49% in the week following the earthquake occurrence, which indicates that more victims evacuated and sought shelter outdoors in cars, tents, and vacant grounds as seen in the case of the Mid-Niigata Earthquake, which witnessed many aftershock activities. Therefore, the evacuation behavior pattern in the Kumamoto Earthquake may be regarded as a cross between the Hanshin-Awaji (Kobe) Earthquake and the Mid-Niigata Earthquake.
-  Fire Defense Agency’s Emergency Response Office, “Earthquake with Seismic Center in Kumamoto District of Kumamoto Prefecture,” Report No.105, Fire Defense Agency’s Document, 2017 (in Japanese).
-  Meteorological Agency’s Earthquake Information, “Information on Seismic Intensities on Japanese Scale in Various Regions,” Meteorological Agency’s Website, 2016 (in Japanese).
-  Meteorological Agency, “Hypocenter Parameters of Earthquakes of Lower 5 or Over on Japanese Scale (the 2016 Kumamoto Earthquake on the website: The 2016 Kumamoto Earthquake),” Meteorological Agency’s Website, 2017 (in Japanese).
-  “Review on Response to the Kumamoto Earthquake in Kumamoto Prefecture (Material at the Cabinet Office’s Second Working Group Meeting to Study Measures of Emergency Response and Life Support in Response to the Kumamoto Earthquake (August 30, 2016)),” Cabinet Office’s Website, 2016 (in Japanese).
-  R. Kimura, “Recovery and Reconstruction Calendar,” Journal of Disaster Research, Vol.2, No.6, pp. 465-474, 2007.
-  R. Kimura, K. Tamura, M. Inoguchi, H. Hayashi, and Y. Urata, “Generalization of victims’ behavior and life reconstruction processes Socio-economic recovery from three earthquake disasters occurred in Hyogo Prefecture in 1995, Niigata Prefecture in 2004 and 2007 –,” Journal of Social Safety Science, No.13, pp. 175-185, 2010 (in Japanese).
-  R. Kimura, K. Tomoyasu, Y. Yajima, H. Mashima, K. Furukawa, Y. Toda, K. Watanabe, and T. Kawahara, “Current Status and Issues of Life Recovery Process Three Years After the Great East Japan Earthquake Questionnaire Based on Subjective Estimate of Victims Using Life Recovery Calendar Method,” Journal of Disaster Research, Vol.9, No.7 (special edition), pp. 673-689, 2014.
-  R. Kimura, M. Inoguchi, K. Tamura, and H. Hayashi, “Comparison Between the Life Recovery Processes After the Mid-Niigata Earthquake and the Chuetsu-Oki Earthquake - Results of a Random Sampled Social Survey Using the Life Recovery Calendar and GIS-Based Spatiotemporal Analysis,” Journal of Disaster Research, Vol.10, No.2, pp. 196-203, 2015.
-  Meteorological Agency, “Estimated Seismic Intensity Maps of the Earthquake That Struck Kumamoto District of Kumamoto Prefecture around 01:26 hours on April 16, 2016 (on the Webpage The 2016 Kumamoto Earthquake),” Meteorological Agency’s Website, 2016 (in Japanese).
-  Ministry of Education, Culture, Sports, Science and Technology, “Final Report of Council on Disaster Education and Disaster Management after the Great East Japan Earthquake,” 2012 (in Japanese).
-  Ministry of Education, Culture, Sports, Science and Technology, “Reference Materials for Disaster Management at School – Development of Disaster Management Education to Foster “Zest for Life”,” 2013 (in Japanese).
-  Meteorological Agency, “Regarding the 2016 Kumamoto Earthquake” (Report No.6) (at 15:30 hours on April 15, 2016), Meteorological Agency’s Press Release Document, 2016 (in Japanese).
-  Sankei Shimbun, [Kumamoto Earthquake] Experts, “The Meteorological Agency’s predictions dwarf its severities”; victims returned home for a while at the information of “aftershock occurrence 20%,” spreading damage, Sankei News at 11:00 hours on April 23, 2016 (Website), 2016 (in Japanese).
-  Mainichi Shimbun, Kumamoto Earthquake, Press Release on Aftershock Probabilities Stopped, Unprecedented Event, Mainichi Shimbun News at 23:18 hours on April 25, 2016 (Final Updates at 23:38 hours on April 25) (Website), 2016 (in Japanese)
-  R. Kimura, H. Hayashi, K. Tamura, S. Tatsuki, T. Noda, K. Yamori, A. Kuromiya, and Y. Urtata, “Developing Victims’ Life Reconstruction Indicators by Social Survey – Ten Years Monitoring in the Great Hanshin-Awaji (Kobe) Earthquake Disaster –,” Journal of Social Safety Science, No.8, pp. 415-424, 2006 (in Japanese).
-  R. Kimura, K. Tamura, and H. Hayashi, “Development of the Method of Clarifying the Life Reconstruction Process Based on the Random Sampled Social Surveys of the Victims – Recovery and Reconstruction Calendar –,” Proc. of the Int. Emergency Management Society (TIEMS) 17th Annual Conf., pp. 168-178, 2010.
-  R. Kimura, “Victims’ Psychology and Society in Disaster,” Encyclopedia of Disaster in Japanese History, pp. 72-77, Yoshikawa-Kobunkan, 2012.
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