Cost-to-coast: space–time modeling of coast defense funds and environmental drivers in Italy

Abstract How do environmental and social factors shape the allocation of public funds for soil defense along Italy’s coastline? Coastal areas in Italy face increasing pressure from both environmental risk and human activities. Yet, despite the importance of soil defense for resilience and risk reduction, little is known about the spatial and temporal dynamics of public funding and the extent to which allocations reflect local environmental and social conditions. This research studies funding decisions behind land protection in coastal municipalities, where human pressure and extreme weather conditions have high impacts. We created a comprehensive dataset by integrating municipal-level funding data from OpenCoesione, OpenBDAP, and ReNDiS with environmental and social indicators. Implementing a spatio-temporal model within the Integrated Nested Laplace Approximation framework, we analyze funding patterns from 2010 to 2023. Our findings offer key insights into some possible socioeconomic and ecological drivers of soil defense investments along the Italian coastline, shedding light on how financial decisions adapt to geographic and temporal dynamics. These insights provide evidence-based guidance for a more equitable and risk-sensitive policy design, supporting better-targeted interventions to face climate and development pressures.