Research on thermal environment simulation improvement of green infrastructure at urban block scale

Abstract

Amid growing concerns over urban heat and climate change, urban planners are increasingly turning to green infrastructure to mitigate thermal stress in dense city environments. This study applies ENVI-met simulations to assess the effects of different green infrastructure strategies–vertical greening, rooftop greening, and permeable pavements–on urban thermal environments across organic and grid street layouts. Simulated variables include air temperature, wind speed, relative humidity, and the Universal Thermal Climate Index (UTCI), rather than pollutants. Results indicate that vertical greening consistently delivers the most effective and stable cooling performance in both street forms, reducing average air temperatures by approximately 0.5°C to 1°C. Permeable pavements enhance humidity and wind flow, making them suitable for areas with limited ventilation. The findings also reveal that street morphology moderates the effectiveness of green infrastructure: organic layouts are more sensitive to wind, while grid blocks benefit from vertical greening as a compensatory cooling mechanism. This study establishes a comparative framework to explore the interaction between urban form and green strategies, emphasising the importance of context-sensitive green infrastructure deployment. It offers practical guidance for improving outdoor thermal comfort, enhancing urban climate resilience, and informing climate-adaptive urban planning.