Approaches for tsunami risk assessment and application to the city of Cádiz, Spain

Abstract

Tsunamis can represent a significant risk to the population and cause huge
economic damage in many costal regions. In order to be able to identify risk hot spots and
implement targeted risk reduction measures, decision makers need to have a clear picture
of the risk situation in their countries or regions. This work reviews existing approaches for
tsunami risk assessment and recommends a five-step process for assessing tsunami risk. As
a case study, a qualitative risk assessment for a worst-case tsunami scenario was carried out
to understand the tsunami risk to the population in Ca´diz. Moreover, a sensitivity analysis
of the tsunami hazard input parameters was performed as a strong influence of the variability
of the input parameters on the resultant tsunami hazard and risk zonation maps was
observed. The study shows that regardless of the assumptions made a non-negligible
tsunami risk to Ca´diz exists.