平流输送数值方案的对比试验

为了分析目前被有限区数值模式所常常采用的平流差分案对计算结果的可能歪曲，如短波分离，位相偏差和振幅哀减等误差特征，给出了二阶（和四阶）—中心、Ｌａｘ－ｗｅｎｄｃｏｆｆ等八种常用方案及一种高精度二阶矩守恒方案的测试结果，给出不同精度方案引入著名的区域模式（ＭＭ４）和１９层输送模式（ＥＭ３）的实例试验结果，结果表明：模式的模拟能力对平流输送过程（模式方程组的非线性平流项）的数值计算精度十分敏感，采用高精度计算方案对改进模式的模拟能力起有重要作用。

COMPARATIVE EXPERIMENT OF NONLINEAR ADVECTION TRANSFER NUMERICAL SCHEME

The simulation and prediction capability of a model relies havily upon the numrical computation technology.The investigation work shows that,the numerical computation accuracy ofr the advection transfer course (the nonlinear advection term of the model equation ) plays an impotant role in the model simulation capability,To disclose the probable distortion (i,e.the error feature such as short wave separation,phase departure and amplitude attenuation etc.) of the advection differential schemes,that are often selected by the current regional mokel,to the computation results,this paper analyzes and measures 8 often useful schemes,such as 2-step matrix scheme.The example test results and figures,for which the different accurate computation achemes enter regional model (MM4) and 19-layer transferl model (EM3), show that the model simulation capability is very sensitive to the computation scheme.Otherwise the results comparison between the regional model example numerical test with different computation schemes and this paper's linear measurement gives necessary basis go the computation scheme selection,and model simulation capaability amalyses and improvement.This it is really significant.