Spatio-temporal Evolution and Driving Factors Analysis of Thermal Environment in Xi'an and Xianyang

Dong Jinfang; He Huijuan; Wang Juan; Wang Zhao; Wang Yani

doi:10.16765/j.cnki.1673-7148.2025.06.006

Abstract：Under the background of global warming and urbanization,exploring the spatio-temporal evolution and driving factors of thermal environment is very significant for reducing urban heat island effect and building ecologically livable cities.Based on Landsat remote sensing images,the land surface temperature(LST)of Xi'an and Xianyang in spring from 1992 to 2022 is extracted.The spatio-temporal evolution of thermal environment and its driving factors are investigated by means of landscape pattern and multi-scale geographically weighted regression.The results show that:(1)The average LST in the study area was in an upward trend from 1992 to 2022.The highest and lowest LSTs have increased in different ranges,leading to a greater dispersion and temperature difference between them.(2)The thermal grades of urban area have been gradually differentiated so that the heat islands in urban area are divided into stronger heat islands,weaker heat islands and non-heat islands.Then,the urban heat island changes from agglomeration to dispersion.The stronger heat islands in rural area have shrunk,while the stronger cold islands have presented an aggregated distribution with the transition from dispersion to agglomera-tion.(3)The landscape metrics reveal that the diversity and evenness of the landscapes in the study area have increased.Fragmentation of landscape types has decreased,connectivity has strengthened,and shapes have become regular due to human disturbance.(4)NDVI and TCW which have negative effects on LST are the main driving factors of the LST evolution.The constant term and NTL have opposite effects on LST at different spatial positions whose interaction intensity with LST are less than those of ND-VI and TCW.