Research on Spatial and Temporal Patterns of Heat Island Variability and Influencing Factors in Urban Center Areas: A Case Study of Beijing's Central Area

Studying the urban heat island effect and actively exploring effective measures for its mitigation and alleviation can provide important parameters for urban ecological environment monitoring and propose rational strategies to address environmental degradation. This article, with the background of urban renewal projects in Beijing, focuses on the central area of Beijing as the research object. Landsat ETM+/OLI_ TIRS data from 2000 to 2020 are used as the main remote sensing imagery source, combined with functional information data and spatial attribute data of open spaces in the central area. Based on the mono-window (MW) algorithm, this study first quantitatively retrieves and categorizes the summer land surface temperature in Beijing's central area and analyzes its spatiotemporal characteristics using the direction distribution method, revealing regular patterns in the temporal and spatial dimensions. The results show a gradual decrease in the size of the persistent high-temperature concentration area over time. Subsequently, the seasonal autoregressive integrated moving average (SARIMA) model is employed to predict the changing trends of the urban heat island and the occurrence time of the strongest and weakest heat islands. Higher land surface temperature (LST) years are projected for 2025 and 2035, with the lowest year being 2030. Lastly, the correlation coefficient and Moran's index are used to analyze the correlation between the urban heat island and its corresponding influencing factors in different years. The results indicate that population density, nighttime light, and gross domestic product (GDP) have significant positive effects on the heat island intensity from a temporal perspective. Normalized difference vegetation index (NDVI) shows a significant negative relationship with the heat island intensity when analyzed over time. The research findings provide important reference for rational urban planning, layout, and construction, and hold significance for advancing urban renewal efforts.