西北干旱区荒漠戈壁陆面过程的数值模拟

首先利用“中国西北干旱区陆 气相互作用试验”2 0 0 0年 5～ 6月在甘肃敦煌进行的陆 气相互作用野外试验的观测资料 ,确定了西北干旱区荒漠戈壁的陆面过程参数 ,并用这些参数改进了已有的陆面过程模式。然后用该陆面过程模式对敦煌陆 气相互作用野外试验荒漠戈壁上的大气感热通量、潜热通量、摩擦速度以及净辐射、地表和土壤温度、土壤水份等重要陆面变量进行了模拟 ,结果表明 ,模拟值与观测值非常接近 ,这说明改进后的模式对干旱区陆面过程有较强的模拟能力

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.