海洋科学学术讲座预告第528期｜Geostationary Satellite Observations of an Episodic Dual-Path Winter Kuroshio Intrusion into the northern Taiwan Strait

  The wintertime Kuroshio intrusion northeast of Taiwan fundamentally regulates cross-shelf mass and heat exchanges in the East China Sea (ECS). However, the highly transient, ageostrophic surface intrusion remains poorly resolved because of temporal aliasing and the inability of traditional altimetry to capture shallow wind-driven flows. Using hourly geostationary ocean color satellite observations combined with three-dimensional numerical vorticity diagnostics, we characterize the synoptic surface flow patterns of this wind-driven intrusion into the Taiwan Strait. We show that during intense winter monsoons, the intrusion frequently bifurcates into a concurrent dual-path flow pattern. Alongside a direct island-bypassing branch that serves as a rapid, coastally constrained advective pathway, we identify a highly transient, surface-trapped shelf-deflection branch that undergoes pronounced cyclonic looping over the mid-ECS shelf. Dynamical diagnostics reveal that the island-bypassing branch transitions into a frictionally dominated flow, whereas the downstream evolution of the shelf-deflection branch suggests that strong lateral shear fundamentally overrides classical topographic steering. Although the initial slope-crossing follows classical topography-induced anticyclonic adjustments, the subsequent cyclonic redirection is dictated by intense lateral shear generated by the collision between Kuroshio surface water and wind-accelerated coastal currents. This study highlights the critical role of  synoptic wind bursts in modulating coastal circulation.