The Spatiotemporal Characteristics and Influencing Factors of Urban Heat Island Effect in Beijing——Taking Chaoyang District and Tongzhou District as Examples

Urban Heat Island (UHI) refers to the phenomenon where the atmospheric and surface temperatures in the central area of a city are higher than those in the surrounding suburban or rural areas. The urban heat island effect can affect urban energy consumption and the health and comfort of residents, while also having adverse effects on urban ecosystems. With the acceleration of urbanization, urban heat island effect has gradually become a widely concerned ecological environment issue. This study used ArcGIS, ENVI and other software to process and analyze Landsat remote sensing images. The thermal field variation index was used to study the spatiotemporal changes of urban heat island effect in Chaoyang District and Tongzhou District of Beijing. The influencing factors of urban heat island effect were analyzed from the perspectives of land use classification, average surface temperature, and epidemic situation. The research results show that: (1) On June 14, 2019, August 3, 2020, June 19, 2021, and July 19, 2023, the urban heat island effect in Chaoyang District, Beijing was slightly higher than that in Tongzhou District; (2) Among the selected research dates, the urban heat island effect in Chaoyang District and Tongzhou District of Beijing was the weakest on August 3, 2020; (3) The land use types that affect the urban heat island in Chaoyang District and Tongzhou District of Beijing are mainly impermeable surfaces and cultivated land; (4) The changes in urban heat island effect are closely related to the average surface temperature. When the average surface temperature increases, the areas of non heat island and weak heat island areas decrease, while the areas of other heat island areas increase. When the average surface temperature decreases, the areas of non heat island and weak heat island areas increase, while the areas of other heat island areas decrease.