A scaling region identification method for the divider dimension of urban thermal environments

Abstract

A scaling region identification method for divider dimensions using the coefficient of determination is proposed to improve the estimation accuracy of the divider dimension in the study of urban thermal environment differentiation characteristics. The effectiveness of this method was verified by analyzing the urban surface thermal field differentiation characteristics by applying the estimated divider dimensions of Nanjing’s thermal environment surfaces and transect lines. The research results show that the urban thermal environment has fractal characteristics only within a certain temperature threshold range. When the constraint of scaling regions is considered, the calculated divider dimension of the surface thermal field surface increases, reflecting the more complex fractal structure of the thermal field. For each temperature grade, the “trough” position of the thermal field divider dimension surface estimated by the line-divider method is near the determination level of the high-temperature region based on robust statistics, allowing the spatial extent of the urban heat island (UHI) to be determined based on the “trough” feature of the thermal field divider dimension surface.