Probabilistic Tsunami Hazard Model of Building Inundation Following a Subaqueous Volcanic Explosion Based on the 1716 Tsunami Scenario in Taal Lake, Philippines

A probabilistic hazard analysis of a tsunami generated by a subaqueous volcanic explosion is performed for Taal Lake in the Philippines. The Taal volcano in Taal Lake is an active volcano on Luzon Island in the Philippines, and its eruption would have a strong impact on humans around the coastal area of the lake. This study aims to develop a probabilistic tsunami hazard model of inundated buildings for tsunami mitigation in future scenarios. To develop the probabilistic tsunami hazard model, different explosion diameters were used to generate tsunamis of different magnitudes in the TUNAMI-N2 model. The initial water level in the tsunami model was estimated based on the explosion energy as a function of the explosion diameter. The tsunami-induced inundation from the TUNAMI-N2 model was overlaid on the distribution of buildings. The statistical distribution of inundated buildings can be modeled with the lognormal distribution, which exhibits the best fit among nine candidate statistical distributions. The tsunami hazard analysis is explained by using the conditional hazard curve and map. These products were used to calculate the probability of building inundation given the occurrence of a subaqueous explosion. The results from this study can be used for future tsunami mitigation in the case of a tsunami generated by a subaqueous volcanic explosion.