基于EOF函数分析局域声速场时空变化特性  

Analysis of Spatio-temporal Variations in Sound Speed Field Based on Empirical Orthogonal Functions

作　　者：朱忆 乔正明 张丽萍 孙文舟 ZHU Yi;QIAO Zhengming;ZHANG Liping;SUN Wenzhou(Office for Establishing Zhangzhou Base,National Ocean Technology Center,Xiamen 361000;State Key Laboratory of Geo-information Engineering,Xi'an 710054)

机构地区：[1]国家海洋技术中心漳州基地筹建办公室,厦门361000 [2]地理信息工程国家重点实验室,西安710054

出　　处：《舰船电子工程》2025年第3期169-172,177,共5页Ship Electronic Engineering

基　　金：地理信息工程国家重点实验室自主课题基金项目(编号:SKLGIE-2022-ZZ2-02);中国博士后科学基金项目(编号:2022M723888);国家自然科学基金面上项目(编号:42374012);国家重点研发计划(编号:2020YFB0505801)资助。

摘　　要：论文主要基于经验正交函数(EOF)对南海某区域的实测声速剖面数据进行分析,研究包括声速场在温度跃变层和深海等温层的时空变化特性、不同源的声速测量系统误差对EOF空间函数的影响以及声速场时空变化对EOF空间函数的影响。此外,还基于面积差法提出了EOF函数阶数的选取策略。实验结果表明,声速场时空变化十分复杂,EOF函数描述后没有明显的特征成分;声速场空间上的变化呈现出较强的随机性且扰动量级小于时间维度,时间上的变化主要发生在温度跃变层,且对第一阶EOF空间基函数的影响明显。This article primarily analyzes the measured sound speed profile(SVP)in a certain region of the South China Sea using Empirical Orthogonal Function(EOF).The study investigates the spatio-temporal variation characteristics of the sound speed field(SSF)in temperature gradient layers and deep isothermal layers,the influence of different SVP measurement system er-rors on the EOF spatial functions,and the impact of spatio-temporal variations in the SSF on the EOF spatial functions.Additional-ly,an approach based on the area difference method is proposed for selecting the order of EOF functions.Experimental results indi-cate that the spatiotemporal variation of the SSF is highly complex,and after describing with EOF functions,there are no obvious characteristic components.The spatial changes in the SSF exhibit strong randomness,with perturbations smaller in magnitude com-pared to the temporal dimension.Temporal changes mainly occur in the temperature gradient layers and have a significant impact on the first-order EOF spatial basis function.

关 键 词：声速场 经验正交函数 面积差法 方差贡献度 

分 类 号：P229[天文地球—大地测量学与测量工程]