Multi-scale Characteristics of the Urban Heat Island Intensity in Shanghai

The characteristics of the urban heat island(UHI) intensity in Shanghai were studied and calculated using wavelet transformation, based on per hour difference in temperatures in 2000 observed from Davis automatic stations installed at the Urban and Suburb of Shanghai.The results show that the period characteristics of UHI in Shanghai are asymmetric,which correspond with the period extending between wavelet amplitude centers and the strengthening of wavelet amplitude.Wavelet transformation can be used to analyze UHI synoptically.The UHI appears obvious on 14 hour-scale and 26 hour-scale in winter, while 12 hour-scale and 28 hour-scale in summer.The UHI in winter is stronger and more obvious than in summer.