Impacts of Land Use/Cover and Urban Morphology on Surface Urban Heat Island and Thermal Comfort in the Severe Cold Region, China

Land use and urban morphology are major factors influencing urban thermal environment. This study explores the relationship between land use/cover and the urban thermal field variance index and the coupling of urban morphology, urban thermal field variance index, and physiologically equivalent temperature in cold regions. Landsat images were used to analyze the evolution of the urban thermal environment in Harbin, China. Ten urban morphological parameters were extracted from 172 city blocks. Multiple regression equations combined with structural equation modeling were used to explore these relationships. The results indicate a 28.25% expansion of the built-up area, with surface temperatures increasing by 3.67 °C, 7.32 °C, 1.72 °C, and 7.18 °C across the four seasons. The areas of strongest level urban thermal field variance index increase are 48.03 km2, 204.01 km2, 135.74 km2, and −134.22 km2. Street morphology was significantly associated with seasonal UTFVI, while the effects of SVF differed between summer and winter. The PET analysis further showed significant relationships between urban morphology and outdoor thermal comfort across seasons. Green space ratios above 0.46 and LAI values of 3.39–5.25 were associated with relatively favorable outdoor thermal comfort. These findings provide insights for urban planning and design aimed at improving outdoor thermal comfort in severe cold regions.