Coupling relationship of land surface temperature, impervious surface area and normalized difference vegetation index for urban heat island using remote sensing

The comparison of the normalized difference vegetation index (NDVI) and percent impervious surface as indicators of surface urban heat island effects in Landsat imagery were researched by investigating the relationships between the land surface temperature (LST), percent impervious surface area (%ISA), and the NDVI. Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) data were used to estimate the LST for the Hangzhou City, China. A map of percent impervious surface was generated using a normalized spectral mixture analysis of July 2003 Landsat TM imagery. The results indicate there is a strong linear relationship between LST and percent impervious surface, whereas the relationship between LST and NDVI is much less strong. This result suggests percent impervious surface was a accurate index instead of the traditionally applied NDVI for analyzing LST quantitatively over the seasons for surface urban heat island studies.