卫星资料反演湿度场改变模式初值对降水预报的影响  

THE INFLUENCE OF INITIAL CONDITION ADJUSTMENT USING SATELLITE-DERIVED HUMIDITY ON PRECIPITATION FORECASTING

作　　者：齐艳军[1] 王汉杰 程明虎[1] 

机构地区：[1]中国气象科学研究院,北京100081 [2]空军第七研究所,北京100085

出　　处：《应用气象学报》2003年第6期663-673,共11页Journal of Applied Meteorological Science

基　　金：中国科学院知识创新工程项目ZKCX2 SW 2 1 0;空军专项KJ0 2 2 5 3课题资助

摘　　要：为探讨初始场资料在数值预报中的重要性 ,用高分辨率卫星TBB资料反演的云内湿度场来改进模式初值 ,初步研究分析了改进的模式初值对降水预报的影响。以湿绝热过程的变态方程为积分方程 ,由卫星TBB资料反演出大气中各等压面层湿度场。通过对比分析反演的湿度场与客观分析 (T1 0 6)的水汽场 ,发现两者有较大区别 ,前者更加合理地反映出降水区域高空湿度场的分布。利用中尺度模式MM5将有限区域的常规探空资料和非常规资料进行同化 ,并对暴雨个例进行预报对比试验。不同初值的对比试验表明 ,在模式的初始场中引入卫星资料反演的湿度场后 ,明显地改善了模式降水预报的强度和落区 ,比仅使用常规探空资料更接近于实况。To improve the accuracy of model initial field, a preliminary analysis of the impact of initial condition adjustment using satellite-derived humidity on the precipitation forecasting is carried out. Taking the wet-adiabatic equation as integral equation, the humidity field on each standard isobaric surface derived from satellite TBB-data is used to improve the model initial conditions. An inter-comparison study is carried on between the satellite-derived humidity and T106 objective analyzed humidity. It is found that there is a big difference between the model-outputs driven by two different humidity fields. The simulation results driven by satellite-derived humidity depict the upper air humidity distribution above the precipitation region very well. Thus, a data assimilation technique based on the meso-scale model MM5 is performed to assimilate the conventional observation data and the high-resolution satellite-derived data. A rainstorm case is simulated in order to compare the precipitation forecast capability with different initial fields. The experiments show that when the satellite-derived humidity is assimilated into the initial condition, both the intensity and the area of simulated precipitation are more close to the measured precipitation as compared with those only using the conventional observations.

关 键 词：卫星资料 反演湿度场 数值模式 初始场 控制试验 

分 类 号：P457.6[天文地球—大气科学及气象学]