1987-2010年PN、TK断面黑潮流场的时空变化

摘要

基于1987-2010年PN断面和TK断面长期水文调查资料,使用逆方法计算了黑潮在这两个断面的流场,进而分析了其时空变化.结果表明,黑潮流量变化的主要周期为准4年和1年,季节变化呈夏强秋弱.两个断面流场的EOF分解的主模态表明:在PN断面,流场变化主要是同位相的,说明了黑潮流量的变化对流场起调控作用;而在TK断面,南北两个海沟中流场呈反位相变化,说明黑潮的路径变化是影响流场变化的主要因素.%Temporal and spatial variability of the Kuroshio at PN and TK sections is studied, based on the geostrophic velocities estimated from the hydrographic data from April 1987 to February 2010 using an inverse method. The Kuroshio volume transport (KVT) exhibits significant seasonal and interannual variability in about 4-year and 1-year periods indicated on the Burg's Power Spectrum. Explained by the principal Empirical Orthogonal Function modes, the Kuroshio velocities at the two sections exhibit distinct temporal and spatial variability. The principal variability mode is almost in-phase at PN section, while anti-phase at the two gaps of the Tokara Strait. That means the variability of velocity structure is mainly controlled by the variation of KVT at PN section, while the migration of the Kuroshio axis at TK section.