高分辨区域输送模式中不同输送格式的对比试验

Comparison of Various Transfer Schemes in a High Resolution Regional Model

本文对两种输送格式在理论试验的基础上，引入１９层高分辨区域输送模式ＥＭ３，由中尺度模式（ＭＭ４）提供实例输送风场。积分至１３、１８、３０、５０、７０小时，作分析和对比数值试验。采用的两种格式是：二阶动量矩守恒的Ｐｒａｔｈｅｒ格式（以下简称为ＳＯＭ）及通量订正的Ｓｍｏｌａｒ格式。数值试验结果表明，高精度的ＳＯＭ格式使数值扩散减小一个量级，使输送物质（ＳＯ２）中心浓度比Ｓｍｏｌａｒ格式增大３～４倍，采用ＳＯＭ格式还明显改进了浓度中心水平平均运动轨迹的模拟精度，选择高精度的平流格式是改进模拟结果的重要途径。

Based on theoretic losts of the two transfer schemes, this paper describes a 19-layer high resolution regional transfer model.EM3,and an example transfer wind field supplied by the mesoscale model(MM4),integration to 13,18,30,50,70 hours,for analytical and comparative numerical test.The tWo schemes are two-order momentum matrix consesration scheme(simplified as SOM) and Smolar scheme,respectively.The numerical results show that the numerical diffusion reduces by an order of magnitude;the central density of transfer material(SO2) differs by a factor of one to two.The simulation accuracy for the central density horizontal mean move-track is significantly improved.The selection of high accurate advection scheme is an important way to improve the model results.