Abstract:

With the development of urbanization，the radiation and energy budget over different urban and suburban underlying surface become increasingly different.Based on the radiation,turbulence flux and fluctuation wind velocity observed by the eddy correlation method on the urban and suburban sites in Nanjing from 27 July to 2 August 2010,the characteristics of the radiation and energy budget over different urban and suburban underlying surface on clear day in summer were analyzed and compared.In order to provide some fundamental characteristics of the radiation and energy budget over different urban and suburban underlying surface,the data observed by Eddy Covariance (EC) observations was studied by using classical statistics.The results show as follows.(1) The radiation over urban and suburban was significantly different on clear day.The average of upward longwave radiation were 5051 W/m2 and 4883 W/m2,and the average of upward shortwave radiation were 246 W/m2 and 395 W/m2 over urban and suburban.The result was related with surface temperature and radiation trap.（2）The energy budget over urban and suburban was significantly different on clear day.Heat storage and sensible heat flux played major roles in urban energy budget.The sensible heat flux in urban was positive all day.The stratification of the atmosphere over urban was always unstable. In suburban,latent heat flux played major role in urban energy budget.The stratification of the atmosphere was stable in night.(3) The average of the diurnal albedo of the urban（33m above the tower）and suburban（2m over the grass）were 011 and 017.The urban albedo was representative characteristic of entirety urban levels of the hundredsmeters diameter.In addition，the suburban albedo showed more serious asymmetry than the urban.(4)The heat storage of urban and suburban were 56% and 7% of the net radiation flux in daytime.Compared with the heat storage of  some others investigations,the characteristic of the heat storage had close correlations with the proportion of hard ground in the observation site and the influence of approved anthropogenic heat.（5）The height of the turbulence flux of the radiation and energy budget observed by the eddy correlation method on the urban was 33 m above the tower on an urban building.The quality of urban turbulence flux datum was good and its reliability was high.Because many factors for the datum like threedimensional urban buildings were of vital importance,the instrument used to observe turbulence flux in urban should be set up in a high position of urban canopy