上海地区高温过程中局地气候区尺度城市热岛特征分析OACSTPCD

This paper takes the mega-city Shanghai as the research object and selects July 2017 as the representative month of summer.Based on the hourly temperature and wind speed data observed by the network of automatic weather stations,the temporal and spatial characteristics of temperature and Urban Heat Island Intensity(UHII)of each Local Climate Zone(LCZ)in Shanghai under different weather conditions were analyzed by using the local climate zone scheme.Results show that the temperature and UHII of each LCZ in the representative summer month in Shanghai are significantly different due to various urban geometry,building materials,the proportion of impervious surface and human activities.On high temperature days,the diurnal variation curves of UHII can be divided into five types:"W"type,shallow"U"type,"V"type,day type and stable type.The urban architectural form has a complex influence on the urban wind and thermal environment.The correlation coefficient between Sky View Factor(SVF)and UHII is negative at 00:00 BST and positive at 12:00 BST and 16:00 BST,which is due to the influence of buildings on the radiative transfer in the urban canopy and the heat storage of buildings.The ratio of urban and rural wind speed is positively correlated with SVF at 00:00 BST,12:00 BST and 16:00 BST,indicating that tall and dense buildings have attenuation effect on wind speed,and the wind speed further affects the intensity of UHII by affecting the advection transport of the atmosphere.