2018 年 18 巻 6 号 p. 6_1-6_22
The rate of fatalities caused by tsunamis vary from community to community depending on geographical and socio-psychological features peculiar to each. If the relationship between fatalities rate and geographical and socio-psychological features can be quantitatively formulated, this can be a concrete means for evaluating a community's vulnerability with regard to evacuation (hereafter, evacuation vulnerability) and developing effective measures that can reduce loss of human life. Therefore, the authors of this paper proposed to apply a Human Vulnerability Index (HVI), defined as fatality rate divided by rate of incidence of washed-out buildings, to evaluate the evacuation vulnerability of municipalities. Using reliable public databases, the authors analyzed the HVIs of twenty municipalities that were heavily damaged by the tsunami of the 2011 Great East Japan Earthquake. Then they applied a multiple-regression analysis using the following four factors as explanatory variables: 1) time allowance for evacuation; 2) preparedness; 3) road serviceability; and 4) warning effect. They thus extracted a reliable formula (R=0.904), which enabled them to quantify the effects of these factors on the HVI. Future tasks are to generalize the formula through application to other tsunami disasters and to establish a numerical evaluation of geographical and socio-psychological features to enable estimation of the tsunami evacuation capability of a municipality and the effect of tsunami countermeasures before a tsunami occurs.
