Evaluation Of Climate Adaptation Strategies in The Nile Delta Coastal Region Using a Multicriteria Framework

Deltaic systems represent global climate adaptation frontiers, facing existential threats from accelerating sea-level rise, land subsidence, and intensifying storms. While hybrid green-grey infrastructure is increasingly advocated, there remains a critical gap in systematic, comparative assessments of diverse hybrid models across environmental gradients, particularly within the data-scarce contexts of the Global South. This study addresses this gap by developing and applying a spatial multi-criteria assessment (MCA) framework to evaluate a pioneering portfolio of four hybrid coastal protection models proposed for the Nile Delta, one of the world's most vulnerable coastal zones. The MCA framework integrates physical performance, ecological integration, and socio-institutional feasibility indicators to conduct a robust ex-ante assessment across five biogeomorphologically diverse hotspots. The analysis identifies Model 3 (Hybrid Rock-Sand Structure) as the optimal solution for high-energy, infrastructure-critical zones where structural integrity is paramount. In contrast, Model 4 (Bio-engineered Dune Formation) is projected to offer superior long-term adaptive capacity and ecological co-benefits in less exposed, environmentally sensitive areas. The findings demonstrate that a strategically diversified portfolio of context-specific hybrid solutions provides greater resilience than any monolithic approach. This research contributes a transferable decision-support framework for portfolio-based, climate-resilient deltaic planning, establishing a paradigm that moves beyond singular technical fixes toward integrated, multi-benefit coastal adaptation under conditions of deep climate uncertainty.