Seasonal and interannual variabilities of mean velocity of Kuroshio based on satellite data  

作　　者：Jun-cheng ZUO Min ZHANG Qing XU Lin MU Juan LI Mei-xiang CHEN 

机构地区：[1]Key Laboratory of Coastal Disaster and Defence of Ministry of Education,Hohai University [2]College of Harbor,Coastal and Offshore Engineering,Hohai University [3]South China Sea Prediction Center,South China Sea Branch,State Oceanic Administration [4]National Marine Data and Information Service

出　　处：《Water Science and Engineering》2012年第4期428-439,共12页水科学与水工程（英文版）

基　　金：supported by the National Basic Research Program of China(973Program,Grant No.2007CB411807);the National Marine Public Welfare Research Project of China(Grants No.201005019,201105010-12,and201105009);the National Natural Science Foundation of China(Grants No.40976006and41276018-74)

摘　　要：Combining sea level anomalies with the mean dynamic topography derived from the geoid of the EGM08 global gravity field model and the CLS01 mean sea surface height, this study examined the characteristics of global geostrophic surface currents and the seasonal and interannual variabilities of the mean velocity of the Kuroshio （the Kuroshio source and Kuroshio extension）. The patterns of global geostrophic surface currents we derived and the actual ocean circulation are basically the same. The mean velocity of the Kuroshio source is high in winter and low in fall, and its seasonal variability accounts for 18% of its total change. The mean velocity of the Kuroshio extension is high in summer and low in winter, and its seasonal variability accounts for 25% of its total change. The interannual variabilities of the mean velocity of the Kuroshio source and Kuroshio extension are significant. The mean velocity of the Kuroshio source and ENSO index are inversely correlated. However, the relationship between the mean velocity of the Kuroshio extension and the ENSO index is not clear. Overall, the velocity of the Kuroshio increases when La Nina occurs and decreases when E1 Nino occurs.Combining sea level anomalies with the mean dynamic topography derived from the geoid of the EGM08 global gravity field model and the CLS01 mean sea surface height, this study examined the characteristics of global geostrophic surface currents and the seasonal and interannual variabilities of the mean velocity of the Kuroshio （the Kuroshio source and Kuroshio extension）. The patterns of global geostrophic surface currents we derived and the actual ocean circulation are basically the same. The mean velocity of the Kuroshio source is high in winter and low in fall, and its seasonal variability accounts for 18% of its total change. The mean velocity of the Kuroshio extension is high in summer and low in winter, and its seasonal variability accounts for 25% of its total change. The interannual variabilities of the mean velocity of the Kuroshio source and Kuroshio extension are significant. The mean velocity of the Kuroshio source and ENSO index are inversely correlated. However, the relationship between the mean velocity of the Kuroshio extension and the ENSO index is not clear. Overall, the velocity of the Kuroshio increases when La Nina occurs and decreases when E1 Nino occurs.

关 键 词：seasonal and interannual variabilities global gravity field global geostrophicsurface current mean dynamic topography KUROSHIO 

分 类 号：P731.27[天文地球—海洋科学]