Remotely sensed monitoring of urban heat island in Chongqing

With the globe climate warming and the extension of urban area, urban heat island has become a serious problem of urban environment. How to effectively monitor the structure and the change of urban heart island is becoming the focus of research on urban environment. Taking the urban core area of Chongqing as the research object, this paper uses Landsat TM/ETM+ imageries in 1988, 2001 and 2006, as well as the observing data of climate station, to study the urban ground temperature. The retrieve method of ground temperature is discussed, including mono-window algorithm, and the process how to get the four parameters of the algorithm. The retrieved ground temperature is standardized with extremum and classified into five temperature zones. The buffer analysis is carried out to detect the spatial structure and its change of urban heart island. The study shows that the character of heart island in Chongqing is great different from that in plain cities. Owing to the effect of special terrain of Chongqing, the heart island has clear hierarchy. The study also shows that the intension and extension of hear island is greatly enlarged from 1988 to 2006 due to the outspread of urban area.