基于趋势项距平值迭进式方差控制的SBE9plus CTD奇异值剔除方法  

A Method for Emilinating SBE9plus CTD Abnormal Values Based on the Trend Anomaly Controlled by Multiple-variance

作　　者：于龙 孙佳 熊学军 郭延良 YU Long;SUN Jia;XIONG Xue-jun;GUO Yan-liang(First Institute of Oceanography, MNR, Qingdao 266061, China;Key Laboratory of Marine Science and Numerical Modeling, MNR, Qingdao 266061, China;Shandong Key Laboratory of Marine Science and Numerical Modeling, Qingdao 266061, China;Laboratory for Regional Oceanography and Numerical Modeling,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China)

机构地区：[1]自然资源部第一海洋研究所,山东青岛266061 [2]自然资源部海洋环境科学与数值模拟重点实验室,山东青岛266061 [3]山东省海洋环境科学与数值模拟重点实验室,山东青岛266061 [4]青岛海洋科学与技术试点国家实验室区域海洋动力学与数值模拟功能实验室,山东青岛266237

出　　处：《海洋科学进展》2021年第4期483-491,共9页Advances in Marine Science

基　　金：国家自然科学基金青年基金项目——中尺度涡对台风强度的影响过程及机理研究(41706034);中央级公益性科研院所基本科研业务费专项资金资助项目——海表温度影响台风强度变化速率的量化规律研究(2020Q05);国家自然科学基金项目——双LADCP深水大洋测量及资料后处理技术研究(41806123)和冬季渤海盐度分布结构近反相变化的机制研究(41506034);国家科技重大专项科研任务——南海北部内波流监测、预报、预警系统研究及应用(2016ZX05057015);青岛海洋科学与技术试点国家实验室区域海洋动力学与数值模拟功能实验室开放基金项目——波浪对卫星遥感资料反演的表层海流的影响(2019A02);国家自然科学基金委员会-山东省人民政府联合资助海洋科学研究中心项目——海洋环境动力学和数值模拟(U1606405)。

摘　　要：针对海洋调查过程中SBE9plus CTD奇异值问题,提出了一种利用趋势项距平值迭进式方差对调查所得的温盐深剖面资料进行奇异值剔除的方法。首先通过EMD(Empirical Mode Decomposition)方法求取最优趋势项进而得到距平;然后根据观测仪器的采样频率和下放速度对距平进行区块分割,通过方差控制识别出奇异值区;接着对每个奇异值区进行逐点判别,再次通过方差控制识别奇异值;最后针对识别出的奇异值,在保证上升过程数据与下降过程数据趋势基本一致且质量可靠的前提下,通过取上升过程相应水层正常数据予以平移替代,从而剔除整个剖面资料中的奇异值。本方法针对SBE9plus CTD剖面资料中的奇异值进行精准识别与靶向剔除,在最大程度保留数据原始特性的前提下,达到一次性尽除奇异值的效果,可为其他高频采样频率的CTD剖面资料奇异值剔除提供参考。To resolve the abnormal value problem of SBE9plus CTD,this paper proposes a method for eliminating abnormal values of the CTD profile data based on the trend anomaly controlled by multiple-variance.Firstly,the optimal trend term is obtained with the EMD method to obtain the anomaly,then the anomaly is divided into blocks according to the sampling frequency and lowering speed of the instrument,and the abnormal value blocks are thus identified through the variance control of all the blocks.Secondly,abnormal value is identified point by point for each abnormal blocks using the variance control of all the blocks again.Finally,under the premise of ensuring that the lifting process data have the same trend with the lowering process data and its quality is reliable,the identified abnormal values are then substituted with the normal data at the corresponding depth during lifting process,so that the abnormal values of the entire profile data are removed.This method can accurately recognize and eliminates the abnormal values in the SBE9plus CTD profile data at one time,while best retaining the original characteristics of the data.It provides a reference for other high-frequency sampling CTD profile data.

关 键 词：SBE9plus CTD 奇异值 EMD 趋势项距平 迭进式方差 

分 类 号：P717[天文地球—海洋科学]