Multi-Hazard Risk Assessment in CZMA Areas: A Geospatial Framework Integrating Future Climate Projections

Coastal Zone Management Act (CZMA) areas in the United States are critical regions where coastal development and environmental conservation converge. Over 50 years, the CZMA has established a federal framework for state-level coastal management, fostering resilience to dynamic challenges. However, these regions increasingly face compounding risks from hazards such as sea-level rise, storm surges, and extreme precipitation, compounded by socio-economic vulnerabilities and geomorphological dynamics.

This study develops a geospatial framework for multi-hazard risk assessment in CZMA areas, integrating geomorphic and sedimentological characteristics with high-resolution datasets and socio-economic indicators to compute a detailed risk index. High-resolution datasets, including satellite-derived shoreline positions and wave and tidal records, are integrated with advanced geospatial and machine learning models, to enhance spatial and temporal projections. Future climate scenarios (2030, 2050, 2100) from CMIP6 datasets are used to assess long-term impacts of sea-level rise and extreme events, with scenario-based modeling addressing uncertainties across different emissions and socioeconomic pathways.

Preliminary findings reveal significant heterogeneity in risk distribution across CZMA areas, with low-elevation coastal plains, deltas, and lagoons identified as the most vulnerable due to geomorphic sensitivity and several challenges to protect them. Our comprehensive map highlights hotspots where erosion, flooding, and socio-economic disparities converge, enabling tailored adaptation strategies. This research bridges policy and science by integrating CZMA legal frameworks with geospatial and technological innovations, offering a scalable and transferable methodology for assessing and managing coastal multi-hazard risks globally.