Tsunami preparedness within a multi-hazard context : summary for policy and decision makers in the Indian Ocean Basin

Abstract

<p>Tsunamis pose a persistent and critical threat to over 20 million people across 13 ESCAP member countries in the Indian Ocean basin, where densely populated coastal regions face escalating vulnerabilities from interconnected hazards such as coastal flooding, cyclones, and rising sea levels—projected to rise by up to 1 meter by 2100. The 2004 Tsunami was a turning point, spurring regional and global investments in early warning systems and fostering collaborative efforts to mitigate tsunami risks. However, despite notable progress, significant gaps in preparedness, response capabilities, and governance persist, hampering the development of comprehensive and sustainable resilience frameworks. Approximately $203 billion in building stock across the region remains exposed to tsunamis and other coastal hazards. Infrastructure, including 1,213 education facilities and 1,450 health facilities, 140 power plants and 1,217 seaports, is at significant risk, exacerbated by the exposure of ecosystems such as mangroves, which are critical for coastal protection. Urban centres like Jakarta, Chennai, and Colombo face heightened vulnerabilities due to high population densities and concentrated economic activities, emphasizing the urgent need for integrated, multi-hazard resilience strategies. </p>

<p>This policy document builds on the Capacity Assessment of Tsunami Preparedness in the Indian Ocean: Status Report 2024 (UNESCO-IOC, forthcoming 2025) and two decades of lessons learned. It evaluates current capacities and identifies opportunities to enhance tsunami preparedness within a multi-hazard context. The policy document emphasizes the need for regional collaboration aligned with global frameworks such as the Sendai Framework for Disaster Risk Reduction, the Early Warnings for All (EW4All) initiative, and the UN Decade of Ocean Science for Sustainable Development (2021-2030). By positioning tsunami preparedness within broader disaster risk reduction strategies, it offers actionable recommendations for policy and decision-makers strengthening resilience and governance against evolving climate and geophysical threats.</p>