Temporal-spatial oceanic variation in relation with the three typical Kuroshio paths south of Japan

• 作者: Xiaobo Wu Yanling Zhao Guijun Han Wei Li Qi Shao Lige Cao Chaoliang Li
• 来源期刊: 海洋学报（英文版）
• 年，卷（期）: 2022,（2）
• 所属期刊栏目: Ocean Data Assimilation
• 页码范围: 15-25
• 页数: 11页
• 语种: 英文

摘要

Empirical orthogonal function (EOF) analysis was applied to a 50-year long time series of monthly mean positionsof the Kuroshio path south of Japan from a regional reanalysis. Three leading EOF modes characterize the contributions from three typical paths of the Kuroshio meander: the typical large meander path, the offshore non-large meander path, and the nearshore non-large meander path, respectively. Accordingly, the spatial variation characteristics of oceanic anomaly fields can be depicted by their regression fields upon the associated three leading principal components (PCs), which are well-matched with the results of composite analysis corresponding to each period of the three typical Kuroshio paths. A new index for the typical large meander is defined by using the second leading PC, which is highly correlated with the Kushimoto-Uragami index. Spectral analysis of this new index series shows variability of the Kuroshio path south of Japan at time scales of about 7–8 years and 20 years.