[Spatiotemporal Evolution and Prediction of Land Surface Thermal Environment in A Typical Ecological City from 1990 to 2020].

Abstract

Rapid urbanization leads to the exacerbation of the urban heat island （UHI） effect, which significantly increases the climate risk of urban heatwaves. The construction of ecological cities, which aim for harmonious development between humans and nature, can substantially mitigate the UHI effect. However, research on the long-term evolution of the land surface thermal environment in ecological urban areas is relatively scarce. Taking the typical ecological city of Suzhou, China as an example, this study analyzes the spatiotemporal evolution pattern of land use changes and land surface thermal environment effects in Suzhou from 1990 to 2020 and predicts the thermal environment for 2030 based on the PLUS model. The results showed that： ① The proportion of built-up areas increased by 3.72%, 11.66%, and 5.67% in 1990-2000, 2000-2010, and 2010-2020, respectively, with built-up land area accounting for 26.83% in 2020, predominantly from the conversion of farmland to built-up areas. ② The UHI intensity showed an increasing then decreasing trend during the study period, with nearly half of the regions experiencing a decrease in UHI levels from 2010 to 2020. ③ Spatially, areas with alleviated heat islands were mainly in the four county-level cities and Gusu District of Suzhou, and the built-up area in the 74.43% of areas with alleviated heat islands increased. ④ The urban heat island intensity of areas expected to change by 2030 is projected to increase by 42.65%, mainly concentrated in the southwest of Changshu City, the central part of Wuzhong District, and the central area of industrial parks on the urban edges and surrounding suburbs, while other areas will show a decreasing trend in heat island intensity. This study demonstrates that the construction of "ecological cities" in Suzhou has significantly reduced the UHI effect caused by urban expansion, providing theoretical references for further development of ecological cities.