||The mechanisms of Kuroshio intrusion onto East China Sea (ECS) were analyzed, applying historical Argos drifter tracks from January 2003 to December 2010, and (EASNFS) numerical modeling results. The relationships of eddies and Kuroshio intrusions were analyzed based on flow velocities, sea surfave high anomalies, and vorticities.|
Results showed that (1) there were 68 drifters intruded, using 200 m contour as boundary, onto the continental shelf ECS, and 18 drifters following the long-term average path of Kuroshio. Drifters intrusion occurred at all seasons, 8 in spring, 13 in summer, 21 in fall, and 26 in winter. (2) Statistics of eddies during drifter intrusion showed 42 cyclonic eddies and 10 anticyclonic (high pressure) eddies, a ratio of 4: 1. There were 16 cases of co-exist anti- and cyclonic eddies. (3) Long-term average flow pattern (8 years of EASNFS) agreed well with the 18 drifter tracks not intruded. This results verified, to centain degree, the robustness of modeling results. The endurance of drifter intrusion showed more persistance in winter and autumn than spring and summer. (4) In spring season, the vorticity in up-stream with high values (0~1.5) might cause the main axis of Kuroshio down stream shifted to coastal region, and consequential Kuroshio intrusion.