Tsunami risk communication and management: Contemporary gaps and challenges

Very large tsunamis are associated with low probabilities of occurrence. In many parts of the world, these events have usually occurred in a distant time in the past. As a result, there is low risk perception and a lack of collective memories, making tsunami risk communication both challenging and complex. Furthermore, immense challenges lie ahead as population and risk exposure continue to increase in coastal areas. Through the last decades, tsunamis have caught coastal populations off-guard, providing evidence of lack of preparedness. Recent tsunamis, such as the Indian Ocean Tsunami in 2004, 2011 Tohoku and 2018 Palu, have shaped the way tsunami risk is perceived and acted upon. Based on lessons learned from a selection of past tsunami events, this paper aims to review the existing body of knowledge and the current challenges in tsunami risk communication, and to identify the gaps in the tsunami risk management methodologies. The important lessons provided by the past events call for strengthening community resilience and improvement in risk-informed actions and policy measures. This paper shows that research efforts related to tsunami risk communication remain fragmented. The analysis of tsunami risk together with a thorough understanding of risk communication gaps and challenges is indispensable towards developing and deploying comprehensive disaster risk reduction measures. Moving from a broad and interdisciplinary perspective, the paper suggests that probabilistic hazard and risk assessments could potentially contribute towards better science communication and improved planning and implementation of risk mitigation measures

Amenaza y riesgo sísmico del Cono Sur

Se presenta la evaluación del riesgo sísmico en Chile y Argentina, siguiendo un enfoque probabilista, con el objetivo de determinar el perfil de riesgo catastrófico de ambos países. Un modelo de amenaza regional fue definido con base en la caracterización del proceso de subducción, los sistemas de fallamiento intraplaca localizados, un catálogo sismológico actualizado y funciones de atenuación espectrales adecuadas, resultando en curvas, mapas y una colección de eventos generados estocásticamente. La exposición se modeló a partir de una representación aproximada de los activos expuestos (proxi), con base en indicadores socioeconómicos nacionales, obteniendo valores de reposición de construcciones e infraestructura, y para los principales sectores económicos de los países. La vulnerabilidad se definió a partir de funciones de vulnerabilidad apropiadas para cada tipo de infraestructura. El riesgo se calculó de manea totalmente probabilista, en términos de la curva de excedencia de pérdidas y la distribución geográfica de la pérdida anual esperada, para diversos portafolios y de manera separada para Chile y Argentina. Finalmente, se presenta una evaluación detallada del riesgo sísmico de la ciudad de Mendoza, donde se incluye la microzonificación sísmica de la ciudad y el catastro detallado, obteniendo una evaluación a nivel de edificaciones para toda la ciudad

Probabilistic Seismic Risk Assessment in Manizales, Colombia: Quantifying Losses for Insurance Purposes

Abstract A fully probabilistic seismic risk assessment was developed in Manizales, Colombia, considering assets of different types. The first type includes elements that are part of the water and sewage network, and the second type includes public and private buildings. This assessment required the development of a probabilistic seismic hazard analysis that accounts for the dynamic soil response, assembling high resolution exposure databases, and the development of damage models for different types of elements. The economic appraisal of the exposed assets was developed together with specialists of the water utilities company of Manizales and the city administration. The risk assessment was performed using several Comprehensive Approach to Probabilistic Risk Assessment modules as well as the R-System, obtaining results in terms of traditional metrics such as loss exceedance curve, average annual loss, and probable maximum loss. For the case of pipelines, repair rates were also estimated. The results for the water and sewage network were used in activities related to the expansion and maintenance strategies, as well as for the exploration of financial retention and transfer alternatives using insurance schemes based on technical, probabilistic, and prospective damage and loss estimations. In the case of the buildings, the results were used in the update of the technical premium values of the existing collective insurance scheme

Tsunami risk communication and management: Contemporary gaps and challenges

Very large tsunamis are associated with low probabilities of occurrence. In many parts of the world, these events have usually occurred in a distant time in the past. As a result, there is low risk perception and a lack of collective memories, making tsunami risk communication both challenging and complex. Furthermore, immense challenges lie ahead as population and risk exposure continue to increase in coastal areas. Through the last decades, tsunamis have caught coastal populations off-guard, providing evidence of lack of preparedness. Recent tsunamis, such as the Indian Ocean Tsunami in 2004, 2011 Tohoku and 2018 Palu, have shaped the way tsunami risk is perceived and acted upon. Based on lessons learned from a selection of past tsunami events, this paper aims to review the existing body of knowledge and the current challenges in tsunami risk communication, and to identify the gaps in the tsunami risk management methodologies. The important lessons provided by the past events call for strengthening community resilience and improvement in risk-informed actions and policy measures. This paper shows that research efforts related to tsunami risk communication remain fragmented. The analysis of tsunami risk together with a thorough understanding of risk communication gaps and challenges is indispensable towards developing and deploying comprehensive disaster risk reduction measures. Moving from a broad and interdisciplinary perspective, the paper suggests that probabilistic hazard and risk assessments could potentially contribute towards better science communication and improved planning and implementation of risk mitigation measures