Optimized Inundation Modeling Using Offshore Hazard Point Tsunami Waveform

The Probabilistic Tsunami Hazard Assessment (PTHA) database provides stochastic synthetic earthquake scenarios. To model tsunami inundation using PTHA database, it is necessary to extract relevant earthquake sources properties or initial sea surface deformations through hazard disaggregation. Simulating tsunami inundation from the source is computationally expensive and time-consuming, especially for far-field tsunami sources. To optimize simulation time, this study focuses on simulating tsunamis from the offshore hazard points (~100 m isobath) by reproducing offshore tsunami-like waveforms of Indian Ocean Tsunami (IOT) 2004. Twelve tsunami events of PTHA18 were tested to reproduce the Indian Ocean Tsunami (IOT) of 2004. The initial sea surface deformation of selected events and offshore tsunami waveform from two relevant points were employed to simulate the inundation. Aida’s parameter and comparison of inundation limits were used to assess the accuracy of the optimized method. The results indicate that the optimized method reduces simulation time by nearly half, significantly improving efficiency. However, inundation extents showed great variability depending on the location of offshore hazard points.