Study of urban heat island and its interplay with impervious surface in Dongguan, China

Impervious surface which is almost never affected by seasonal variations is a key indicator of urban expansion and urban heat island effect. In this study, we employ a new integrated enhancing index to extract impervious surfaces and compare the results with those retrieved by other existing spectral indices. The results show that the new integrated enhancing index can mitigate background noises effectively and achieve satisfactory accuracy. The land surface temperatures (LSTs) are also retrieved from thermal infrared bands of two TM datasets. And the relationships between impervious surfaces and LSTs are then analyzed. Results indicate that LSTs possess a strong positive correlation with percent impervious surfaces at regional-scale. The findings can definitely reveal the correlation of impervious surfaces and urban heat island (UHI) and provide a reference for the urban ecological environment protection.