Adaptive disaster risk assessment : Combining multi-hazards with socioeconomic vulnerability and dynamic exposure

Abstract

Climate change, combined with the rapid and often unplanned urbanisation trends, is associated with a rising trend in the frequency and severity of disasters triggered by natural hazards. Among the weather-related disasters, floods and storms (i.e. hurricanes) account for the costliest and deadliest in the last decades. The situation is of particular importance in Small Islands Developing States (SIDS) because their relative higher vulnerability to the impacts of climate change, due to their location, fragile economies, limited resources, and more vulnerable habitats. Therefore, SIDS must implement adaptation measures to face the impacts of climate change and those of the urbanisation growth; for which is necessary to have an appropriate Disaster Risk Assessment (DRA), which should include the hazard itself, the intrinsic socio-economic vulnerability of the system and the exposure of infrastructure and humans to the hazard. Traditional DRA approaches for disaster risk reduction (DRR) have focused mainly on the natural and technical roots of risk, this is the modelling of the hazard and implementation of physical and structural defences, for which the hazard component is the centre. Traditional DRA methods pay no or little attention to the other dimensions of disaster risk, and do not often investigate the spatial and temporal relationships between the hazard, the vulnerability and the exposure components. A better alternative when dealing with DRA is a holistic risk assessment, which looks at risk as a whole, looking into the components and seeking to understand the interactions, interrelatedness and interdependences between different processes and parts of the whole.