Nighttime cultural districts concentrate dense human activity, intense illumination, and continuous operations, which can generate pronounced nocturnal thermal anomalies that remain insufficiently examined in urban heat island (UHI) research. This study analyzes how nocturnal UHIs form and propagate across five representative music-cultural districts in Changsha, China, between 2013 and 2024. Using multi-source satellite observations in combination with XGBoost, principal component regression, structural equation modeling, and a Gaussian diffusion kernel, we reconstructed high-resolution nocturnal land surface temperature (LST) patterns and assessed the drivers of spatial variability. Results show a steady citywide warming trend, peaking in 2022 with a mean nocturnal LST of 17.03 °C (maximum 21.32 °C), accompanied by increasing spatial heterogeneity. Music-cultural districts showed heterogeneous thermal risk profiles, commercial corridors such as Jiefang West Road were consistently 1.0-2.1 °C hotter than surrounding areas, while river- and park-adjacent districts such as Orange Island and Meixihu functioned as persistent cold islands (- 2.0 to - 2.8 °C). Diffusion analysis revealed corridor-like propagation with gradients of 1.5-4.2 °C km- 1 and effective stochastic diffusion coefficients of 1.30-1.49 m2 s- 1, indicating an influence radius of approximately 2-3 km. Model-based uncertainty and attribution analyses highlighted the dominant role of building density and nighttime lighting (combined importance > 0.6) as risk-enhancing factors, whereas vegetation coverage and water proximity provided robust buffers. Mitigation scenario simulations suggest that isolated measures yield limited benefits (0.25-0.65 °C cooling), while integrated strategies-expanding green-blue infrastructure, enhancing surface albedo, and moderating nighttime traffic-reduce diffusion intensity by 28-35% with cooling effects up to 1.8 °C. These findings demonstrate that nocturnal UHI propagation not only shapes local microclimates but also generates uneven patterns of heat exposure risk within and around music-cultural districts. By treating music-cultural districts as a nightlife-related urban unit, this study offers an in-depth characterization of their nocturnal thermal dynamics, diffusion behavior, and policy-relevant mitigation levers. The proposed framework provides transferable evidence for climate-adaptive planning and public health risk mitigation in cities with vibrant nighttime economies.
Keywords: Heat-Diffusion simulation; Mitigation strategies; Music-Cultural district; Nocturnal urban heat island; Spatial variability.
© 2026. The Author(s).