From measurements to regulations: An actionable approach for sustainable urban cooling via heat-resilient urban planning

The proactive and science-based regulation of excessive urban heating is an urgent priority. However, a theoretical-practical disconnect persists between urban thermal environment research and applicable urban planning strategies, hindering the effectiveness of mitigation and adaptation tools. To address this gap, this study developed a theoretical framework to assess the feasibility of sustainable urban cooling regulation within urban planning systems. It proposed a two-pronged and planning-driven approach of controlling the heat source' and increasing the cooling source for sustainable urban cooling, and using the daily mean temperature-humidity index (DMTHI) to capture humidity and daily land surface temperature dynamics. A case study from the main urban area of Wuhan, China, validated this approach, identifying heat stress hotspots in the old city center and peripheral heavy industrial parks. The key indicators for urban cooling in Wuhan were the mean building density, percentage of industrial land area, and percentage of green space. Based on the K-means method, the 'controlling heat source' strategy identified five regulation zones: building form control, comprehensive control, land use control, industrial and building density control, and building density-dominated control. The 'increasing cold sources' strategy identifies four regulation zones: NDVI-dominated cooling, integrated greenspace cooling, LPI_G-dominated cooling, and PLAND_G-dominated cooling. These site-specific plans improve the efficacy of urban cooling regulation. This study provides insights for mitigating urban heat stress and supports the development of heat-resilient urban planning.