How Numerical Simulations May Contribute to Tsunami Risk Preparedness: The 26 December 2004 Indian Ocean Event and the Thailand Case Study

The tsunami information, i.e. the sea level elevation, presents useful features that can be used for different case studies. It can be derived from observations, e.g. tide gages records or anomaly of sea level obtained with altimeters, but also through numerical modeling of the tsunami propagation. Once a robust numerical simulation is performed, the wave sequence, compared to available hydrodynamical observations, may help in a better characterization of the tsunami source, e.g., earthquake – or landslide-derived tsunami among the most widespread sources. It may be used for refining a source derived from seismological instrumentations (GPS positioning, seismic stations analysis). As a result, a better identification of source parameters along with a reliable ensemble of numerical simulations of the tsunami propagation and run-up within an area is useful for tsunami risk assessment, e.g., tsunami run-up maps and optimization of the tsunami instrumentation for the purpose of a tsunami warning system. In this context we describe the Thailand case study of the 26 December 2004 Indian Ocean tsunami event.