Regenerative Design for Heat-Resilient Cities: Nature-Based Microclimatic Strategies in a Mediterranean Context

Urban areas in Mediterranean climates are increasingly affected by extreme heat, exacerbated by the Urban Heat Island (UHI) effect and the lack of climate-responsive public spaces. This study addresses the need for integrated methodologies combining empirical monitoring and simulation tools to support regenerative urban design. The objective is to evaluate the effectiveness of Nature-Based Solutions (NBSs) in improving microclimatic conditions and outdoor thermal comfort during summer heatwave periods in a vulnerable urban area in Seville (Spain). A mixed-method approach combining microclimatic monitoring and ENVI-met simulations in situ was applied. A field campaign conducted in summer 2023 was used to characterize baseline conditions and calibrate the model, which simulated both current and proposed scenarios incorporating vegetation, shading systems, permeable materials, and water features. Results from the Seville case study show significant improvements, with air temperature reductions of up to 1.6 °C (daytime) and 1.9 °C (nighttime), surface temperature decreases of up to 11 °C, and thermal comfort improvements reaching 8 °C in UTCI. Beyond environmental benefits, the intervention promotes socially regenerative public space by enhancing usability, inclusivity, and comfort. Limitations include the use of a single representative summer day and inherent simplifications of the ENVI-met model. These findings demonstrate the potential of integrated NBS strategies to mitigate urban heat and support climate-adaptive and socially responsive urban design.