Understanding International Cooperation Potential in Coastal Multiple Hazards Governance Through Risk Similarity

Abstract

Multiple hazard risks (MHRs) in coastal zones will continue to increase due to climate change and rising sea levels. These disproportionate impacts create shared challenges that require cross-border mitigation efforts. However, understanding how coastal areas exhibit common risk patterns and how such patterns can inform risk-based cooperation remains fairly limited. Here, we investigated international cooperation potential among 126 coastal countries from an integrated perspective of their risk similarity, geopolitical stance, and knowledge exchange. We conducted a high-resolution assessment of multiple hazard risks (including earthquakes, landslides, flooding, and cyclones) and developed a bottom-up similarity measure to identify common risk profiles across regions from both size and space. Our analysis revealed a notably high degree of risk similarity across country pairs, suggesting greater potential for cooperation than that previously recognized; 89% of country pairs with high risk similarity lacked strong partnerships in consensus-building or knowledge-sharing. This cooperation gap was even more pronounced in the Global South and small island developing states. Instead of relying solely on geographic proximity or existing alliances, we argue for a shift in focus toward partnerships grounded in shared risk challenges. This approach can help to build collective resilience to achieve Sustainable Development Goals for climate action (SDG 13) and partnerships for the goals (SDG 17).