Interannual Modulation of Kuroshio in the East China Sea Over the Past Three Decades

Previous studies have suggested that westward-migrating mesoscale eddies are a dominant factor modulate the interannual Kuroshio intensity in East China Sea (ECS), indicating close positive correlation between them. According to extended record of altimetry-based sea level anomalies (SLAs) until 2020, however, variation no longer has strong with eddy activity subtropical countercurrent (STCC) region since early 2000s. Our observational analyses showed ECS can be modulated by combined effect and westward-propagating oceanic planetary waves from east. Until 2000s, variability was mainly affected migration STCC region, associated instability driven large-scale wind patterns over western North Pacific. Since then, propagating westward across Pacific basin largely ECS-Kuroshio superimposing SLAs related propagated towards east Taiwan.