Urban Climate Adaptation in Naples: An Integrated Framework for Flood Risk, Urban Heat Island, and Nature-Based Intervention Planning.

densely built cities, the progressive replacement of permeable sur- faces with impervious, heat-retaining materials simultaneously reduces infiltration capacity, amplifying urban flood risk and limits evapotranspiration, thus intensify- ing the Urban Heat Island (UHI) effect. These two climate-related hazards share a common structural driver and are particularly severe in compact, socially heteroge- neous urban neighbourhoods where green infrastructures are scarce and drainage systems are ageing. This paper proposes an integrated methodology for urban climate adaptation applied to three Naples districts (Fuorigrotta, Ponticelli, Soc- cavo), combining: (i) flood risk mapping through coupled EPA SWMM+FLO-2D hydraulic modelling and CubiST machine learning vulnerability assessment; (ii) open space microclimate simulation via ENVI-met to quantify thermal co-benefits of greening scenarios; and (iii) spatially explicit Low-Impact Development-Best Management Practices (LID-BMP) and greening siting based on compound risk overlay. For flood risk (R), the formulation R = H × E × V allows integrat- ing the hydraulic hazard (H) with socio-economic vulnerability (V) and expo- sure (E) into a composite index suitable for spatial planning. For UHI, where no analogous probabilistic risk framework is established in the literature, thermal performance is assessed through ENVI-met simulations comparing the baseline scenario with design ones including post-greening open space configurations. Cooling co-benefits through PET and outdoor air temperature are also quantified. Results show that nature-based interventions in open spaces generate compound reductions in both flood risk and thermal stress, providing local decision-makers with a physically grounded, spatially explicit evidence base for urban renewal investment.