p-σ混合坐标原始方程模式对地气交换的敏感性试验

THE EFFECTS OF THE DIURNAL VARIATIONOF SOLAR RADIATION ON CLIMATEMODELING OF R15L9

在五层及九层ｐ－σ混合坐标有限区域原始方程模式中，选择几种方案对影响地气系统之间动量、热量交换的拖曳系数进行了敏感性试验，并以一次寒潮为试验个例。试验结果表明：模式结果对拖曳系数的选取是敏感的；原模式对该系数在青藏高原地区的取值偏小，增大高原地区的ＣＤ取值能取得更好的预报效果。

Comparative analyses are made between the experiments with and without the diurnal variation of solar radiation by use of the R15L9 model. The simulated mean sea level pressure, 500hPa height, the surface temperature and the precipitation fields of both January and July are discussed and compared. Statistical tests are also made. The results indicate that the diurnal variation of solar radiation has significant effects on the climate modeling,particularly in the Northern Hemisphere and on the continents. Ignored diurnal variation of such physical process would certainly influence the results of the climate modelling and induce systematic errors.