An improved, SSH-based method to automatically identify mesoscale eddies in the ocean

  • WANG Xin ,
  • DU Yun-yan ,
  • ZHOU Cheng-hu ,
  • FAN Xing ,
  • YI Jia-wei
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  • 1. State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; 2. Geomatics College, Shandong University of Science and Technology, Qingdao 266510, China

Received date: 2011-10-30

  Revised date: 2012-11-04

  Online published: 2013-06-10

Supported by

Fundation item: This study is jointly supported by a grant from the National Natural Science Foundation of China (General Program) (41071250) and Innovation Program of State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (088RA500KA)

Abstract

Mesoscale eddies are an important component of oceanic features. How to automatically identify these mesoscale eddies from available data has become an important research topic. Through careful examination of existing methods, we propose an improved, SSH-based automatic identification method. Using the inclusion relation of enclosed SSH contours, the mesoscale eddy boundary and core(s) can be automatically identified. The time evolution of eddies can be examined by a threshold search algorithm and a tracking algorithm based on similarity. Sea-surface height (SSH) data from Naval Research Laboratory Layered Ocean Model (NLOM) and sea-level anomaly (SLA) data from altimeter are used in the many experiments, in which different automatic identification methods are compared. Our results indicate that the improved method is able to extract the mesoscale eddy boundary more precisely, retaining the multiple-core structure. In combination with the tracking algorithm, this method can capture complete mesoscale eddy processes. It can thus provide reliable information for further study of reconstructing eddy dynamics, merging, splitting, and evolution of a multi-core structure.

Cite this article

WANG Xin , DU Yun-yan , ZHOU Cheng-hu , FAN Xing , YI Jia-wei . An improved, SSH-based method to automatically identify mesoscale eddies in the ocean[J]. Journal of Tropical Oceanography, 2013 , 32(2) : 15 -23 . DOI: 10.11978/j.issn.1009-5470.2013.02.002

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