一次典型华南暴雨预报目标观测区的确定和敏感性试验  

IDENTIFICATION OF ADAPTIVE OBSERVATION AREAS OF A TYPICAL SOUTH CHINA RAINSTORM PROCESS AND SENSITIVE EXPERIMENTS

作　　者：路秀娟[1,2] 钟青[2] 邵洋[1] 张红雨[3] 

机构地区：[1]中国气象局应急减灾与公共服务司,北京100081 [2]中国科学院大气物理研究所云降水物理与强风暴实验室,北京100029 [3]山西省气象局,山西太原030002

出　　处：《热带气象学报》2013年第5期857-864,共8页Journal of Tropical Meteorology

基　　金：国家自然科学基金资助项目(41075078;41275109);中国气象局气象新技术推广重点项目(CMATG2010Z07);公益性行业(气象)科研专项(GYHY201106049)共同资助

摘　　要：针对一次典型华南暴雨过程,利用适应性观测技术确定对华南暴雨预报起关键作用的敏感区,并设计一组试验方案,以目前国内实际地面观测站点分布为前提,在敏感区内增加不同数量的均匀随机分布的地面观测资料,通过MM5(The Fifth PSU/NCAR Mesoscale Model)三维变分(3DVAR)同化系统对已有的地面观测站点资料和敏感区内所增加的观测进行同化,考察地面观测站点的分布对关注区域内预报效果的影响。试验结果表明,各试验对降水的预报差异不大;而以扰动总能量的大小衡量预报水平,与CTRL试验相比,在敏感区内增加观测对短时临近数值预报效果的改善尤为明显,若敏感区内增加75%的地面观测,可使24 h后的关注区域内的数值预报水平提高12.6%,而随着敏感区内地面观测站点的增加,关注区域内的预报水平并没有得到相应提高,这说明布设过多的地面观测站点不但不能改善预报效果,反而造成资源浪费。因此,这一结果为充分利用有限资源、更好设计地面观测站网、最大限度提高华南暴雨的预报水平有很好的理论指导作用。A typical South China rainstorm process is studied and the technique of adaptive observation is used to identify the sensitive area,which is crucial to the forecasting in South China.In the context of the real distribution of existing surface observations,a set of experiments are designed by adding various hypothetic surface observations that distribute symmetrically and randomly in the sensitive area.Both existing and hypothetic observations are assimilated simultaneously by MM5-3DVAR,and then the forecasting effect in the areas concerned is investigated.The result shows that the difference of rainfall is little and when the forecast is evaluated with total disturbance energy,compared with the experiment of CTRL,the improvement of short-term forecast and nowcasting is clearer when more observations are added to the sensitive area,and if 75％ stations of the existing observations are added in the sensitive area,the forecast in the area concerned can be improved by 12.6％.With the observations in the sensitive area increasing,the forecast cannot be improved significantly,which shows that instead of improving the forecast,more observations can cause the redundancy of resources.So the result,in theory,can be used to conduct the construction of surface observation stations in order to make full use of limited resources and improve the rainstorm forecast in South China.

关 键 词：目标观测 敏感区 华南暴雨 

分 类 号：P426.616[天文地球—大气科学及气象学]