AUTHORS: Jia Wang *, Weiqi Zhou – State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences
ABSTRACT: Rapid urbanization leads to the Urban heat island (UHI) phenomenon which affects ecological processes and human health. Previous studies largely investigate the dynamics of temperature in the urban areas, and focus on single city level based on the thermal remote sensing data or the long time series of meteorological data. However, few studies have revealed the real dynamics of land surface temperature (LST) due to its spatial heterogeneity from multiscale levels (city level, urban-rural gradient and hot spot zone). In this study, we presented a general framework for analysing the dynamics of urban thermal environment from a multiscale perspective in Beijing, using the annual average summer LST from 2000-2015 based on MODIS global LST 8-day data. We found that: 1) The average LST and UHII were increasing significantly from 2000-2015 in urban areas, but varied greatly in urban areas with different development degree. The increase rates of average LST and UHII in the new urban areas were higher than those in the old urban areas; 2) The rates of LST increased with the increase of distance from urban core; 3) Overall 3.41% of the study area had a significantly positive trend of LST with the rate of 0.19?/a, mainly distributed in Daxing, Tongzhou and Changping Districts. This study can enhance our understanding of urban thermal environment dynamics from different scales. The findings are considered important so as to promote sustainable urbanization, as well as provide important insights to UHI mitigation plans in Beijing.
