Day and night: Impact of 2D/3D urban features on land surface temperature and their spatiotemporal non-stationary relationships in urban building spaces

The spatiotemporal non-stationary relationships between 2D/3D urban features and land surface temperature (LST) introduces uncertainty to the quantitative exploration between them. This study focused on the urban building spaces of "furnace city" Fuzhou and explored the quantitative relationships between urban features and ECOSTRESS diurnal LSTs from a block perspective. Our results revealed that: (1) Compared to the ordinary least squares regression model, the multi-scale geographically weighted regression model can better capture the spatiotemporal non-stationary relationships. (2) Largest patch index of building patches (LPI_B) and building height (BH) have the greatest impact on the variations in daytime and nighttime LSTs, respectively. The interaction between largest patch index of vegetation patches (LPI_V) and LPI_B has the largest enhancing effect on daytime LST, while BH and LPI_B enhances nighttime LST the most. (3) The diversification of architectural morphology highlights the equal importance of both 2D and 3D building features in influencing LST variations. Meanwhile, the standardization of urban greening emphasizes the greater significance of vegetation features in 2D compared to 3D. (4) Differentiated urban renewal schemes should be adopted based on varying spatial characteristics. These findings can deepen our understanding of spatiotemporal non-stationarity that cannot be ignored in urban thermal environment research.