NUMERICAL SIMULATION OF THE LAND-SURFACE PROCESS OVER DESERT AND GOBI IN ARID REGION OF NORTHWEST CHINA

In this paper, the paramet ers of the land-surface process over Gobi in arid region of North west China are as-certained firstly by utilizing the field observation dat a of Land-Atmosphere Interaction Experiment over Arid Region of Northwest China in Dunhuang of Gansu Province from May to June of 2000.For example, the soil thermal capacity mean is(1.12 0.27) 106 J/(m3 K), the soil thermal conductivity mean is 0.274 0.017 W/(m K), the soil thermal diffusivity mean is(2.52 0.63) 10-7 m2/s.The results are smaller than those got in HEIFE.The surface roughness leng this 0.0019 m.The at mospheric transparent coefficient mean is 0.61 which is smaller than that in the wetregion.And the parameterized formula of the at mospheric transparent coefficient is gotover the desert and Gobiaffected by the sand weather.With these parameters the land-surface process model is advanced.Then, the numerical simulations of the sensible heat, the latentheat, the friction velocity, the netradiation, the surface and soil temperatures and the soil moisture over Gobi in the field experiment are done.The correlation coefficients between the simulation results and the observations for the sensible heat flux, the latent heat flux and the friction velocity are 0.95, 0.58 and 0.64 respectively.The net radiation maximum is close to 500 W/m2.The results show that the simulation and the real observation are very close and the advanced model has strong simulative ability for the land-surface process overarid region.