jismart2024020: Research on the cumulative cooling effect of urban shading in summer

Abstract

In the context of climate change and the urban heat island effect, urban areas experience significant heat stress in summer. However, with the expansion of urban vertical space, these 3D urban landscapes also possess inherent shading potential. This paper investigates the cumulative cooling effect of urban shading on the land surface temperature (LST) using Nanjing, China as a case study. A 3D city model was constructed using LiDAR data to explore temporal changes in shading patterns. By using multi-temporal thermal infrared image data collected throughout the day, the relationship between shading and LST over time was explored. The results indicate that shading can reduce LST by an average of approximately 1.97 °C to 5.53 °C during the day, with a potential cumulative cooling effect observed over the previous 3 to 5 hours. This study aims to explore the potential cooling effect of shading cast by 3D urban forms to mitigate heat stress. Furthermore, we aim to quantify the dynamic shading potential, facilitating the incorporation of dynamic shading as a heat mitigation strategy in urban planning.