中尺度数值模式MM5的四维变分资料同化系统  

The Four-Dimensional Variational Data Assimilation System of Mesoscale Numerical Model MM5

作　　者：王栋梁[1] 沈桐立[1] 田洪军[1] 

机构地区：[1]南京气象学院气象灾害和环境变化重点开放实验室,江苏南京210044

出　　处：《南京气象学院学报》2002年第5期603-610,共8页Journal of Nanjing Institute of Meteorology

基　　金：国家自然科学基金项目 40 0 75 0 2 3;国家自然科学基金项目 40 175 0 0 7;国家重点基础研究项目 G19980 40 910

摘　　要：应用伴随方法求解以数值预报方程作为约束条件的四维变分资料同化方案 ,关键问题是如何构造伴随模式。以中尺度数值模式 MM5为例 ,讨论了如何用伴随码技术建立 MM5伴随模式 ,以及伴随模式系统中权重、尺度因子的选取 ;最后对 MM5伴随模式系统进行了梯度检验 ,并利用实际资料进行四维变分资料同化试验。试验表明该系统有较强的同化能力 ,能够提高 MM5降水预报的准确性。The key problem of four-dimensional variational data assimilation method,which solves the constraining numerical predict equations through accompanied model,is how to establish an accompanied model.Taking the mesoscale numerical MM5 model for example,it is discussed how to set up MM5 accompanied model by making use of accompanied code technique and how to choose weighting and scaling factors in the accompanied model system.Furthermore,the conventional observations are done in the MM5 model system,and a four-dimensional variational data assimilation test is made based on observed data.The results show that this system has powerful assimilation capacity and is able to improve the accuracy of MM5 model rainfall forecast.

关 键 词：中尺度数值模式 中尺度模式MM5 四维变分资料同化 伴随模式系统 伴随码 数值预报 

分 类 号：P456.7[天文地球—大气科学及气象学]