Field Measurement of the Large Urban River Effect on Urban Thermal Climate

This study is carried out from a three -day field measurement in studies of the potential effects of urban river on urban thermal climate and thermal comfort, using fixed point observation method in the summer of Harbin and the sites are located in the section of Songhua River Basin. Fixed point measurement on the research of river impact on the urban climate is developed based on the theory of water surface heat balance. The measurement comprises of heat dynamic budget utilizing heat balance method and water and air temperature varieties above the river and other underlying surfaces. The description of thermal comfort can also be obtained by SET* utilizing mean radiant temperature and other variables. After a series of data collection and analysis, During the sunny days, ground surface temperature is mostly affected by solar radiation while it is about 14°C higher than air temperature above the river. Net radiation rate is large enough to reach 700W/m², while sensible heat flux and latent heat flux account for a small proportion of net radiation: only 0.6% and 5.8% respectively, which means that the main part of net radiation from water surface returns to the atmosphere in the way of convective heat transfer and mass transfer.