Rec-EOF质量控制方法在地面观测2m比湿中的应用  

Application of recursive EOF quality control to 2 m specific humidity from ground-based observations

作　　者：赵虹[1,2] 冯呈呈[1,3] 刘寅[1,4] 

机构地区：[1]南京信息工程大学资料同化研究中心,南京210044 [2]南京市六合区气象局,南京210044 [3]大连市气象局,辽宁大连116000 [4]江苏省气象探测中心,南京210009

出　　处：《气象科学》2015年第5期638-645,共8页Journal of the Meteorological Sciences

基　　金：国家重点基础研究发展计划(973计划)项目(2010CB951600);江苏省普通高校研究生科研创新计划(CXZZ13_0503;CXLX13_483;CXZZ13_0506);江苏高校优势学科建设工程资助项目(PAPD)

摘　　要：针对地面观测站资料,从资料同化的角度出发,通过引入递归的概念,提出了递归经验正交质量控制(Rec-EOF QC)方法,并将该方案应用于不同时段的地面观测资料和不同种类的背景场资料中。结果表明:Rec-EOF QC方法一般在递归4次之后,质量控制过程达到稳定状态。通过递归方法,该质量控制方案能够通过资料本身调整质量控制的临界值,对资料具有普适性。而且与传统EOF QC方法相比,Rec-EOF QC方案能识别出更多的离群值,并且可以使观测偏差也更接近于高斯分布。另外还研究了背景场差异对质量控制的影响,分别利用FNL、ERA-Interim和JRA-25三组资料作为背景场进行地面质量质量控制试验,结果表明JRA-25剔除的资料最多,ERA-Interim次之,FNL最小。无论选用何种资料作为背景场,冬季的资料剔除率始终大于夏季的。n order to improve the surface observation data assimilation from ground-based stations,through introducing the recursive theory, a recursive EOF quality control（Rec-EOF QC） method is putforward and is applied to the surface observation data with different periods and the background field datawith different varieties. Results show that the quality control process of Rec-EOF QC method is stable as aresult of four times of recursion. The Rec-EOF QC method can adjust the threshold of the quality controlby the data itself and is universally applicable to different data. Compared with the traditional EOF QCmethod, the Rec-EOF QC scheme can identify more outliers and can make the observation error moreclose to Gaussian distribution. In addition, FNL, ERA-Interim and JRA-25 datasets are selected as back-ground fields to conduct surface quality control test, whose results show that outliers identified by JRA-25 as background data are the maximum, ERA-Interim takes the second and FNL is the minimum. Moreo-ver, outliers are identified more in winter than those in summer regardless of what kinds of data were cho-sen as background.

关 键 词：湿度 地面观测比湿 质量控制 递归经验正交 

分 类 号：P413.2[天文地球—大气科学及气象学]