青藏高原地表分类及其东北部辐射通量的二维数值模拟

通过对青藏高原地区地表特征的格点分类及沿五道梁站的经向二维中尺度数值模拟,结果发现：青藏高原地区１３类地表特征都有,尽管其植被自西北向东南呈带状分布,但仍十分复杂;而其地表特征的这种格点分类为该地区的高分辨数值模式模拟提供了极其有用的下边界条件。地面净辐射通量及其诸分量的模拟结果与观测结果的相当接近与一致表明,该模式具有模拟青藏高原地区地面通量日变化的能力。模拟结果和观测分析还指出：夏天睛天条件下

CLASSIFICATION OF QINGHAI-XIZANG PLATEAU LANDUSE AND TWO-DIMENSIONAL NUMERICAL SIMULATION OF RADIATION FLUX ON ITS NORTHWEST PART

Trough the results of the classification for Qinghai Xizang Plateau landuse and meridional two dimensional numerical simulation along Wudaoliang in this paper, we found that 13 landuse categories all are existed, in spite of its vegetation exhibiting a few bands from northwest to southeast, but the landuse is still very complex. This classification of the landuse at grid points provides a quite useful surface boundary condition for high resolution numerical model and simulation in this region. The considerable closeness and consistence of the simulated and observed results for the surface net radiation flux and its components shown that this model possesses a capacity of simulating diurnal variation of surface flux in Qinghai Xizang Plateau region. The simulated result and observed analysis also indicated that the solar net short wave radiation was the main component in the surface radiative energy budgets under the clear sky condition during summer, its peak value 884 W/m 2 is obvious greater than that of other places in our country, the single peak value interval occurred between 12:00BST(04:00UTC) and 14:00BST(06:00UTC) was consistent with the surface outgoing long wave radiation, but it advance one hour. The diurnal variation of atmospheric downward long wave radiation and the surface net radiation, this is related to a complex variation of cloud over Qinghai Xizang Plateau region. The mean value of single peak value of the surface net radiation was about 584 W/m 2, but their peak values exhibited obvious difference due to the different underlying surfaces. The evolution and structure of the sensible heat flux in cross section revealed a few important features.