Flood and landslide risk mapping based on a multi-criteria analysis (MCA) in Greater Abidjan (Côte d’Ivoire)

Abstract. This study presents a multi-hazard risk assessment of flood and landslide hazards in the Greater Abidjan metropolitan area of Côte d’Ivoire, aimed at enhancing disaster risk reduction strategies in data-poor contexts. Using a semi-quantitative approach within a multi-criteria decision-making framework, specifically the Analytic Hierarchy Process (AHP), we assess both hazard and vulnerability factors contributing to flood and landslide risks, incorporating climatic, environmental, and social aspects. An innovative validation method is introduced, leveraging a multi-source database of past disaster events in the region, combining information from well-established disaster loss databases and results from field surveys, thereby enhancing the robustness and reliability of the results. The findings identify risk-prone areas within Greater Abidjan and provide actionable insights for improving disaster risk management. This approach, which builds on previous research by incorporating both flood and landslide risks, advances a multi-hazard perspective and contributes to a deeper understanding of hazard dynamics in Greater Abidjan. It also offers a model that can be applied to similar urban settings across sub-Saharan Africa.