System Sciences

Abstract. The primary background for the present study was a project to assist the authorities in Thailand with develop-ment of plans for how to deal with the future tsunami risk in both short and long term perspectives, in the wake of the dev-astating 26 December 2004 Sumatra-Andaman earthquake and tsunami. The study is focussed on defining and analyz-ing a number of possible future earthquake scenarios (mag-nitudes 8.5, 8.0 and 7.5) with associated return periods, each one accompanied by specific tsunami modelling. Along the most affected part of the western coast of Thailand, the 2004 tsunami wave caused a maximum water level ranging from 5 to 15 m above mean sea level. These levels and their spatial distributions have been confirmed by detailed numerical sim-ulations. The applied earthquake source is developed based on available seismological and geodetic inversions, and th