Progress on circulation dynamics in the East China Sea and southern Yellow Sea: Origination, pathways, and destinations of shelf currents

In recent years, advances have been made toward understanding the oceanic circulation dynamics in the Taiwan and Tsushima straits, as well as over the central shelf of East China Sea (ECS) and southern Yellow Sea. ECS shelf circulation between the 50 m and 100 m isobaths is attributed to the confluences of the northeastward Taiwan Strait Current (TSC) and Kuroshio intrusion over the shelf to the northeast of Taiwan. Although the relative importance and interaction of these two currents have not been well documented, the driving mechanisms underlying the northeastward TSC have been extensively studied in recent decades. The first set of long-term (2009–2011) observations showed that a stronger/weaker TSC (~2.37 Sv/~0.64 Sv) appears in summer/winter. However, the dynamics underlying the northeastward TSC against the northeasterly winds in winter are still debatable. The destination of the ECS shelf current in the formation of the Tsushima Warm Current is better understood. The volume transport of this current is ~2.67 Sv. The northeastward-flowing Taiwan Warm Current has two branches over the 50 m and 100 m isobaths. The northwestward Yellow Sea Warm Current (YSWC) characterizes the shelf circulations in the Yellow Sea Trough in winter, and the propagation of coastally trapped waves greatly regulates the flow pattern of the YSWC. The Yellow Sea Cold Water Mass alters the shelf circulations in the southern Yellow Sea in summer.