Ocean Science www.ocean-sci.net 1812-0784 1812-0792 5 3 2009 10.5194/os-5-303-2009 http://www.ocean-sci.net/5/303/2009/ http://www.ocean-sci.net/5/303/2009/os-5-303-2009.html http://www.ocean-sci.net/5/303/2009/os-5-303-2009.pdf 303 312 2009-08-03 The Kuroshio exchange with the South and East China Seas T. Matsuno matsuno@riam.kyushu-u.ac.jp J.-S. Lee S. Yanao Research Institute for Applied Mechanics, Kyushu University, Japan Ocean Research Team, National Fisheries Research & Development Institute, Korea Department of Earth System Science and Technology, Kyushu University, Japan The Kuroshio flows along the edges of the marginal East Asian seas such as the South China Sea (SCS) and East China Sea (ECS). Exchanges of materials and energy between the Kuroshio and the marginal seas partly control the environments of the marginal seas. In particular, saline water from the Kuroshio maintains certain salinity in the shelf water in the ECS. Nutrients from the subsurface of the Kuroshio may influence primary production on the shelf. We summarize how the Kuroshio comes into contact with the shelf water or marginal seas, describing phenomena related to the exchange between the Kuroshio and the ECS along with the SCS, using reports in the literature along with original data. The Kuroshio tends to intrude into the SCS through the Luzon Strait in various manners such as direct intrusion, associated with eddies and as a loop current. The Kuroshio intrusion into the shelf region of the ECS has distinct seasonal variation and the Taiwan Warm Current plays a significant role in the determination of water properties in the outer shelf associated with the Kuroshio intrusion. We then examine physical processes related to the interaction between the Kuroshio and shelf water. Interaction between the Kuroshio and the bottom topography is an important process in the control of the exchange around the shelf break. Vertical mixing and frontal eddies are also important factors that control the water exchange and formation of water masses in the outer shelf. Wind stress plays a significant role in the exchange with a rather event-like manner. To determine the source of the water masses, chemical tracers could be powerful tools and it is suggested that a significant part of the shelf water consists of Kuroshio intermediate water. % vor jede Referenz Bai , L. and Zhang, J.: Shelf water mass origins and nutrient flux estimation in the East China Sea using low-volume seawater measurement with rare earth element, Adv. Geosci., in press, 2009. Chang, P.-H. and Isobe, A.: A numerical study on the Changjiang Diluted Water in the East and Yellow China Seas, J. Geophys. Res., 108(C9), 3299, doi:10.1029/2002JC001749, 2003. Chen, C. T. A. and Wang, S. L.: Carbon, alkalinity and nutrient budgets on the East China Sea continental shelf, J. Geophys. Res., 104(C9), 20675–20686, 1999. Chen, C. T. A., Liu, C. 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