Tsunami vulnerability assessment in the Southern Boso Peninsula, Japan

The Boso Peninsula is located in East Japan north of the Sagami Trough, which has historically given tsunamigenic earthquakes. We have selected the southern part of the peninsula, namely the villages of Aihama and Mera, which belong to the city of Tateyama, and used a tsunami vulnerability assessment tool (Papathoma Tsunami Vulnerability Assessment model) for 358 buildings located there, for a tsunami scenario with a maximum run-up of 10 m. Additionally, we applied a building population estimation model, which allowed us to estimate the population residing in the different vulnerability categories as they resulted from the assessment tool. The results show that 28% of the buildings have very high vulnerability, 16% have high vulnerability and 20% have average vulnerability. For these vulnerability categories the population estimation model showed that from 407 residents, 94 reside in buildings with very high vulnerability, 72 in buildings with high vulnerability and 91 in buildings with average vulnerability. Population demographics of local inhabitants indicate high chances of residents belonging in sensitive age groups, and potentially rendering them more vulnerable during their escape from a tsunami event and the following recovery from it.