Characteristics of multi-scale temporal-spatial distribution of urban heat island in Guangzhou
广州城市热岛空间分布及时域－频域多尺度变化特征

Hourly data were collected from 47 automatic weather stations in Guangzhou to calculate the Guangzhou urban heat island(UHI)intensity in January,April,July and October 2001.The Kriging interpolation showed that the spatial variation of Guangzhou UHI was closely correlated with underlying surface,man-made heat,atmospheric pollutant and weather system,and the analysis on the temporal variation from January 2001 to February 2002 by Morlet wavelet transform revealed that there were multi-scale UHI periods.The main time scales were daily,weekly and bimonthly periods,and the secondary time scale was trimestral period.Sea-land breeze,man-made heat,long wave radiation of earth surface,and heat exchanges on earth surface affected the daily period,human activities affected the weekly period,solar radiation and weather system affected the bimonthly period,while monsoon affected the trimestral period.This temporal-spatial variation of Guangzhou urban heat island was deeply affected by the coactions of weather system,long wave radiation,underlying surface,atmospheric pollutant,man-made heat,and heat exchanges on earth surface,etc.