有限区分析预报系统及其业务应用

中国国家气象中心在新开发的有限区多元最优插值分析技术及１５层球面网格原始方程模式的基础上建立了一个新的有限区分析预报系统。１９９１年投入业务使用，主要用于２４－４８ｈ降水预报。这个系统是依附于全球同化预报系统的一个分支系统。亦即使用全球谱模式６ｈ预报作为初估值进行有限区细网格分析及使用其１２—６０ｈ预报作为侧边界值进行非同步嵌套预报。作为一个升级模式系统，它的进步表现在：较充分使用了卫星测湿资料及地面资料的细网格多元最优插值分析；同时使用同场及质量场初值，成功地实现了有限区非线性正规模初始化处理；采用位涡拟能守恒差分格式，包含较真实地形的球面坐标原始方程模式；实现了具有不同模式地形的差分模式与谱模式的嵌套及设计了分级降水客观检验系统。

THE LIMITED AREA ANALYSIS AND FORECAST SYSTEM AND ITS OPERATIONAL APPLICATION

he limited area analysis and forecast system (LAFS) was developed and has been put into operational use at National Meteorological Center since January 1991. This system can be regarded as a branch system attached to the global assimilation and medium-range forecast system which is based on a spectral model T42L9. The main advancements as an upgrade operational system are: the use of a regional fine mesh OI analysis schem; the realization Of the non-linear normal mode initialization for the regional model: the development of a 15L-spherical grid PE model (with real topography and enstrophy conservation) and its nesting forecast with the spectral model T42L9.