This paper compares the normalized difference vegetation index (NDVI) and percent impervious surface as indicators of surface urban heat island effects in Landsat imagery 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 from four different seasons for the Twin Cities, Minnesota, metropolitan area. A map of percent impervious surface with a standard error of 7.95% was generated using a normalized spectral mixture analysis of July 2002 Landsat TM imagery. Our analysis indicates there is a strong linear relationship between LST and percent impervious surface for all seasons, whereas the relationship between LST and NDVI is much less strong and varies by season. This result suggests percent impervious surface provides a complementary metric to the traditionally applied NDVI for analyzing LST quantitatively over the seasons for surface urban heat island studies using thermal infrared remote sensing in an urbanized environment.
Bibliographical noteFunding Information:
The support of the Department of Geography, Minnesota State University, Mankato and the Department of Forest Resources and Agricultural Experiment Station (project MN-42-037), University of Minnesota, is gratefully acknowledged. Many thanks also go to all the reviewers for their constructive comments and suggestions.
Copyright 2008 Elsevier B.V., All rights reserved.
- Impervious surface area
- Land surface temperature
- Landsat TM/ETM+
- Normalized difference vegetation index
- Spectral mixture analysis
- Surface urban heat island