Reviewing the multi-hazard concept. Application to volcanic islands

Because of their social, economic and political contexts, and their intrinsic multi-hazard nature, volcanic islands are one of the most vulnerable environments, where natural hazards (volcanic and non-volcanic) tend to occur in a simultaneous way causing cascading effects. To date, most of the scientific knowledge, as well as hazard assessment and risk management protocols focus on individual hazards and risks, while it remains a challenge to correctly predict the outcomes and impacts of a multi-hazard scenario where several hazardous phenomena may interact in simultaneous or consecutive ways. The multi-hazard concept originated in the 1990s in the international political context precisely to respond to this need. After its first appearance, different–and often, contradictory–usage perspectives of the multi-hazard concept have been increasingly put forward, thus making it difficult for this new approach to be fully implemented into disaster reduction policies. The present study assesses the current status of the application of the multi-hazard approach in existing risk management systems, and proposes future improvements to disaster risk reduction. It also presents the multi-hazards to which volcanic islands are exposed and analyses their potential impacts, taking the Canary Islands as a case study. In doing so, it emphasizes the need to establish a cross-sectoral, climate change-oriented, socially-inclusive, multi-risk management system, based on scientific knowledge and linked to critical societal demands and solutions.