有限尺度李雅普诺夫指数与海表温度梯度相关性的初步分析  

Preliminary Analysis of the Correlation Between Finite Size Lyapunov Exponent and Sea Surface Temperature Gradient

作　　者：曹蕾 张杰 杨俊钢 周超杰 孙伟富 崔伟 CAO Lei;ZHANG Jie;YANG Jun-gang;ZHOU Chao-jie;SUN Wei-fu;CUI Wei(First Institute of Oceanography,MNR,Qingdao 266061,China;Ocean Telemetry Technology Innovation Center,MNR,Qingdao 266061,China;College of Oceanography and Space Informatics,China University of Petroleum,Qingdao 266580,China;College of Oceanic and Atmospheric Sciences,Ocean University of China,Qingdao 266100,China)

机构地区：[1]自然资源部第一海洋研究所,山东青岛266061 [2]自然资源部海洋遥测技术创新中心,山东青岛266061 [3]中国石油大学(华东)海洋与空间信息学院,山东青岛266580 [4]中国海洋大学海洋与大气学院,山东青岛266100

出　　处：《海洋科学进展》2020年第1期130-139,共10页Advances in Marine Science

基　　金：国家重点基础研究发展计划项目——全球高分辨率海洋再分析系统研制与产品研发(2016YFC1401800);“全球变化与海气相互作用”专项——西太平洋PAC-YGST04区块海洋环境参数遥感调查Ⅱ期(GASI-02-PAC-YGST2-04)。

摘　　要：为了探究海表温度和海面高度之间的瞬时相关性,介绍了一种卫星测高数据的拉格朗日分析指数--有限尺度李雅普诺夫指数(Finite Size Lyapunov Exponent,FSLE),以黑潮延伸体区域的涡旋和南大西洋的亚南极锋为例,通过对观测、模式结果和融合产品结果的分析,探讨了该指数与海表温度梯度(Sea Surface Temperature Gradient,SSTG)之间的相关性。比较FSLE图像和SSTG图像发现,FSLE与SSTG均呈丝状结构,对海洋表层水体结构描述具有一致性,尤其在温度梯度大和地转流强的区域更为一致。二者的一致性要远好于其他常用方式,比如全流速、OW参数涡旋识别方法和Winding-Angle涡旋识别方法。不同区域FSLE与SSTG之间的相关性表现不同,黑潮延伸体区域相关系数存在显著的季节变化,而南大西洋亚南极锋区域季节内变化突出。In order to explore the instantaneous correlation between Sea Surface Temperature(SST) and Sea Surface height(SSH), this paper introduces a Lagrangian analysis index for satellite altimetry, the finite-scale Lyapunov exponent(FSLE), and explores the correlation between this exponent and the sea surface temperature gradient(SSTG) using observations, model results and merged products, with the areas of Kuroshio extension and the south Atlantic subantarctic front as examples. By comparing the FSLE image and SSTG image, it is found that both FSLE and SSTG are typically in the form of filaments, and their description of ocean surface structure is consistent, especially in regions with large SSTG and strong geostrophic velocity. Their consistency is far superior to common methods, such as total velocity, OW parameter vortex detection method and Winding-Angle vortex detection method. The correlation between FSLE and SSTG depends on the region. The correlation coefficient in the Kuroshio extension region has significant seasonal variation, while the intra-seasonal changes are prominent in the south Atlantic subantarctic front region.

关 键 词：有限尺度李雅普诺夫指数 海表温度梯度 拉格朗日拟序结构 相关性 

分 类 号：P731.11[天文地球—海洋科学] O172[理学—数学]