Risk and Vulnerability Assessment to Tsunami Hazard Using Very High Resolution Satellite Data - The Case Study of Padang, Indonesia

Tsunamis are an ever-present threat to lives, infrastructure, and property along the coasts of the world's oceans. Recent tsunamis deeply impacted the shores of Indonesia, calling for early warning systems as well as risk and vulnerability assessment as basis for mitigation strategies, evacuation planning and rehabilitation organization. Research on tsunamis focuses on tsunamis generation, wave propagation, inundation and interactions with structures. This study is focusing on the latter, using the capabilities of high resolution satellite data to assess tsunami vulnerability in urban areas. Based on an object-oriented land-cover classification the physical urban morphology is structured using parameter like built-up density, function, building sizes or location. The distribution of a total population following the structural characteristics of an urban morphology is determined by assuming a dependency between numerical and spatial units. Using the derived physical and demographic parameters, risk and vulnerability patterns are calculated for the tsunami exposed coastal city of Padang, Indonesia. The aim to support the preparation of an action plan for evacuation based on the spatial risk and vulnerability analysis of the derived layers. This spatial knowledge base enables the identification of safer areas, the location and amount of affected people and houses, or the planing of space-oriented evacuation routes.