Abstract:With the wind,temperature and humidity profile data obtained at Jilantai station,Inner Mongolia from April 20 to May 10 in 1996 and at Alashan Youqi station,Inner Mongolia from April 5 to May 27 in 1997,the momentum,sensible and latent heat fluxes have been calculated by an aerodynamic method.Furthermore,the diurnal variations of the fluxes in different dust and sand weather conditions over the desert area have been analysed.The results suggest that the diurnal thermal turbulence is stronger than the dynamic turbulence in the surface layer and the most important material exchange is sensible heat turbulent exchange in a clear sky; in a dust and sand floating weather,the turbulent transfer is weaker than that in a clear sky;in a dust and sand blowing weather,the turbulent exchange of momentum is as same important as that of sensible heat,and the peak value of turbulent momentum flux is about one order greater than that in a clear sky,moreover,the peak value of turbulent sensible heat flux is greater than that in a dust and sand floating weather,but smaller than that in a clear sky; as for sandstorm weather,the turbulent exchange of momentum is as same important as that of sensible heat,and the turbulent exchanges are greater than those in a dust and sand blowing weather,as a result,the strong sensible heat takes an important role in the generating and strengthening of sandstorms.