{"title":"Water Exchange Through the Upper and Middle Luzon Strait Using the Sigma–Pi Diagram","authors":"Hua Zheng, Xiao-Hua Zhu","doi":"10.1029/2024JC021092","DOIUrl":null,"url":null,"abstract":"<p>Water exchange in the Luzon Strait (LS) is critical for layered circulation in the South China Sea (SCS); however, observational evidence of sandwich-like water exchange is scarce. This study presents a comprehensive analysis of the meridional and zonal spatial patterns of water exchange in the upper and middle LS, along with its seasonal variations in a sigma–pi diagram using Argo profiles. As observed viewed from the perspective of SCS, inflow and outflow occur in the upper and middle layers, respectively. Upper-layer Kuroshio intrudes into the SCS primarily in the northern and central regions of the LS, extending along the continental shelf into the inner SCS. A significant middle-layer eastward outflow is evident at 26.7–27.56 kg/m<sup>3</sup> (500–1,500 m) in the northern part of the strait, extending to 123°E. The Kuroshio intrusion intensifies during the winter, whereas the middle-layer outflow is most pronounced in the autumn.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":null,"pages":null},"PeriodicalIF":3.3000,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Geophysical Research-Oceans","FirstCategoryId":"89","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1029/2024JC021092","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"OCEANOGRAPHY","Score":null,"Total":0}
引用次数: 0
Abstract
Water exchange in the Luzon Strait (LS) is critical for layered circulation in the South China Sea (SCS); however, observational evidence of sandwich-like water exchange is scarce. This study presents a comprehensive analysis of the meridional and zonal spatial patterns of water exchange in the upper and middle LS, along with its seasonal variations in a sigma–pi diagram using Argo profiles. As observed viewed from the perspective of SCS, inflow and outflow occur in the upper and middle layers, respectively. Upper-layer Kuroshio intrudes into the SCS primarily in the northern and central regions of the LS, extending along the continental shelf into the inner SCS. A significant middle-layer eastward outflow is evident at 26.7–27.56 kg/m3 (500–1,500 m) in the northern part of the strait, extending to 123°E. The Kuroshio intrusion intensifies during the winter, whereas the middle-layer outflow is most pronounced in the autumn.