Analysis of Urbanization Effect on Land Surface Temperature, Using Sub-Pixel Technology

In this study, Landsat TM and ETM+ images in 2000 and 2008 were selected to study the spatial and temporal dynamics of thermal environment in Guangzhou at a sub-pixel level. The Linear spectral mixture model (LSMM) was used to derive vegetation fraction images. Then trajectory analysis was performed in the vegetation-LST space, to evaluate the impact of urbanization on the surface thermal environment of Guangzhou. The results showed that in the vegetation-temperature space, pixels migrated from the low temperature-dense vegetation condition to the high temperature-sparse vegetation condition. Process of urbanization in Guangzhou has caused a notable increase in the land surface temperature of certain land cover types. Urbanization has also made urban heat land moved toward north of Guangzhou.