Assessing the Effectiveness of Urban Green Infrastructure for Heatwave Mitigation

This study investigates the impact of urban green spaces on human thermal perception during heatwaves in Szeged, Hungary. Utilizing the MUKLIMO_3 micro-scale climate model and perceived temperature (PT), calculated via the Klima-Michel model, as a metric for thermal load, we analyze the effects of varying vegetation types, densities, and placement, including the influence of surrounding protective forests.  PT, an energy balance stress index, integrates air temperature, humidity, radiation, and wind, providing a comprehensive measure of human thermal sensation. Our results demonstrate the potential of targeted green space development to significantly reduce PT, particularly during daytime, with dense tree cover exhibiting the most substantial cooling effect, reaching reductions of 2-3°C in certain areas. However, we also highlight the importance of considering the airflow-blocking effect of dense vegetation, which can lead to localized warming in downwind areas. This underscores the complex relationship between green infrastructure and urban microclimates. Furthermore, the influence of green spaces on nighttime temperatures is nuanced, with some configurations potentially trapping heat. This study pioneers city-wide human comfort simulations, utilizing the model based on the Local Climate Zone (LCZ) system to elucidate the interplay between urban vegetation and thermal comfort. The model's capability to incorporate regional climate model outputs provides a foundation for future human comfort assessments. This research offers valuable insights for urban planners and policymakers seeking to enhance city resilience to climate change. By understanding the complex interactions between green spaces, urban morphology, and thermal comfort, cities can optimize green infrastructure development for maximum cooling benefits. The study emphasizes strategic urban planning incorporating microclimatic considerations and equitable access to green spaces. Our findings contribute to a deeper understanding of urban greenery's microclimatic benefits, particularly in medium-sized cities, and offer a framework for future urban climate modeling using the LCZ system for effective heat management.