As a part of Sino-Japanese Joint Research Program on Atmosphere-Land Interaction in the Heihe River Basin (HEIFE), a preliminary observation of turbulent characteristics and turbulent transport in the surface boundary layer over an oasis in the desert area has been made in succession to that on the Gobi desert (Wang and Mitsuta, 1990 and 1991). Different from the conditions over the desert, the latent heat flux is as much as four times of the sensible heat flux and plays a dominant role in the energy budget.
The specific humidity shows a peak twice a day, a little before noon and in the evening. The air temperature fluctuation shows its maximum in the evening when its mean value is falling off. The normalized variance of temperature and specific humidity are both well described by a universal function of stability, showing that they follow the Monin-Obukhov similarity.