Spatial and temporal analysis of urban heat Island effects in Chengdu City by remote sensing

Abstract

This paper studied temporal and spatial changes of Urban Heat Island Effects (UHI) in Chengdu City, Sichuan Province of China, using LandSat ETM+/TM data. Urban Black-body Temperature (TBB) was obtained. The findings are showed as follow: (1) UHI is extremely remarkable within the Third Ring Road of Chengdu City. (2) In terms of spatial changes, in 1988, the high temperature zone mainly occurred in the downtown within the First Ring Road. In 1999, UHI gradually extended from the city center to the Second Ring Road, and urban center was no longer the center of heat island. In 2006, UHI mainly occurred in the east, southwest and northwest of the city outside the Third Ring Road. (3) In terms of quantity changes, the heat island area in 1988 was 7146.54 hm2, which accounted for 36.95% of study area; that in 1999 was 6490.26 hm2, which accounted for 33.56%; that in 2006 was 5259.42 hm2, which accounted for 27.19%. From 1988 to 2006, the heat island distribution area gradually reduced and UHI showed decreasing trends.