Abstract
The probability of simultaneous occurrence of tsunami and storm surge is small. Once it happens, however, the impact could be enormous. This study considers the joint probability of the two phenomena in terms of a probabilistic hazard analysis. A probabilistic typhoon model is used to simulate long-term storm surge time series, then the probability distribution of tide and storm surge is produced. Tsunami exceedance probabilities are set hypothetically by tsunami heights and return periods. Then the overall exceedance probability considering tsunami, tide, storm surge, is calculated. We argue the probability level at which the effect of storm surge is significant, and we also test the effect of tsunami height characteristics on the relative strength of storm surge effect.
Evaluations are performed at Nagoya and Maizuru. In the scope of the present study, the probability level of significant effects of storm surge by simultaneous occurrence of tsunami and storm surge is calculated to be several magnitudes smaller than the occurrence probability of tsunami.
