Tsunami Hazard Area Predicted by Probability Distribution Tendency

Abstract

The recent occurrence of tsunamis that have caused a significant loss of human life and property has aroused considerable attentions to the natural disaster. Tsunami disaster prevention policy is generally focused on the creation of hazard maps based on virtual tsunamis. To increase the efficacy of such maps, the flooding hazard area at one location, Jumunjin Port, was predicted in this study. The flooding height expected to cause human losses was determined, and the probability of the simulated tsunami flooding exceeding this height was calculated at each point of the grid covering the flooding hazard area. To obtain the flooding data, a numerical simulation was conducted of the propagation and inundation of a virtual tsunami. To determine the probability distribution type of the flooding data, a goodness-of-fit test, namely, the probability plot correlation coefficient (PPCC) test, was used, and the normal, lognormal, exponential, and Gumbel distributions were assumed to be the probability distribution types of the flooding height data. The best-fit probability distribution type among the four probability distribution types was determined at each point. The probability of flooding exceeding the criterion height was calculated for each grid point using the cumulative distribution function (CDF) that corresponded to the best-fit probability distribution. The lognormal distribution was found to be the most appropriate distribution type for the tsunami flooding height.