USING LANDSAT-8 DATA TO EXPLORETHE CORRELATION BETWEEN URBAN HEAT ISLAND AND URBAN LAND USES

Abstract

On a local scale, climate change can potentially exacerbate the urban heat island (UHI) effect characterized by an abrupt thermal gradient between urbanized and nearby non-urbanized areas. While it is well-known that the presence of impervious surfaces and less vegetation influence urban microclimate, relatively little attention has been given to the spatial patterns of urban heat islands and how these patterns are affected by land use. In this study, we derive land surface temperature (LST) from Landsat 8 data over four time frames and analyze the relationship between urban thermal environments and urban land use. Landsat 8 Thermal Infrared Sensor (TIRS) and Operational Land Imager (OLI) band data are converted to top-of-atmosphere spectral radiance using radiance rescaling factors. At-satellite brightness temperature was retrieved and the land surface emissivity was calculated. In addition, Normalized Difference Vegetation Index and Normalized Difference Built-up Index were computed and their correlations with LST for each land use were examined. The results indicate that the highest maximum land surface temperature was observed in high density residential and commercial areas near city's downtown. Coastal areas and areas near water bodies are found to have lower land surface temperatures. The results from this study can inform planning and zoning practices aimed at reducing the urban heat island effect and creating a cooler and more comfortable thermal environment for city residents.