Assessing coastal flood risks : modeling sea level rise and inundation scenarios for the northeast coastline of Malta

Abstract

Sea level rise poses an urgent threat to Malta’s northeast coast, where urban density, economic activity, and critical infrastructure converge. This study addresses the pressing challenge of sea level rise along Malta’s northeastern coastline, a region characterized by dense urban development, critical infrastructure, and significant economic activity. Given the limited availability of high-resolution, location-specific flood modeling in Malta, the research aims to support evidence-based planning and climate adaptation strategies. Despite growing recognition of coastal vulnerability, Malta lacks spatially explicit risk assessments that account for both long-term SLR and short-term hydrodynamic drivers. This research investigates the extent of inundation and infrastructure exposure under a range of climate scenarios. The study integrates Coupled Model Intercomparison Project Phase 6 (CMIP6) outputs with high-resolution Digital Elevation Models (DEMs), tidal records, and wave height data. Both magnitude-based (+0.5 m, +1.0 m, +1.5 m) and scenario-based (SSP-RCP) sea level projections were applied to generate detailed inundation maps and quantify shoreline loss. Results indicate a nonlinear increase in coastal inundation, with up to 51.5% recreational shoreline loss under high-magnitude scenarios. Under SSP5-8.5 by 2100, projected flood levels, including wave height and tide, may exceed 4.9 meters, posing severe risks to coastal roads, urban infrastructure, and essential facilities such as the Pembroke reverse osmosis plant. The findings underscore the need for integrated, anticipatory coastal adaptation frameworks in Malta. By providing location-specific flood risk assessments, this research supports informed policy development and enhances national capacity for climate resilience planning.