黑潮延伸体中尺度涡年代际变化与北太平洋风暴轴变化之间的关系

The Relationship between Mesoscale Eddies in the Kuroshio Extension Region and Storm Tracks in the North Pacific

利用18年带通滤波的卫星高度计资料，通过引入黑潮延伸体中尺度涡能量（EKE）的面积指数，分析了黑潮延伸体中尺度涡EKE的强度和位置的年代际变化特征，并使用回归分析等方法分析了它们与北太平洋风暴轴之间的关系。结果表明，黑潮延伸体中尺度涡增强与北太平洋风暴轴的增强相对应，而EKE位置偏北（南）时对应的北太平洋风暴轴也偏北（南），同时当EKE的位置偏东（偏西）时北太平洋风暴轴则西退（东移）。此外，北太平洋风暴轴的变化对黑潮延伸体也可能有一定的反馈作用，黑潮延伸体中尺度涡EKE强度的变化与北太平洋风暴轴EOF第一和第三个模态（第二个模态）回归的海表面高度距平模态有明显的3～4年滞后的正（负）相关，而黑潮延伸体中尺度涡EKE位置的变化则相反。这种滞后相关可能是通过北太平洋风暴轴驱动的遥相关型环流改变海表面风应力旋度并强迫出的海表面高度距平的西传导致的。

AbstractUsing 18 years of Band-pass filtered sea surface height （SSH） data from satellite altimeters, the relationship between the mesoscale eddy kinetic energy （EKE） in the Kuroshio Extension （KE） region and North Pacific atmospheric storm track is investigated by introducing the EKE area index and using regression analysis. A stronger North Pacific storm track was found to be associated with intensified Kuroshio Extension mesoscale eddy activity. The North Pacific storm track shifts northward （southward） as the maximum EKE core in the KE region shifted to the north （south）. However, the variation between the EKE and North Pacific storm track is reversed in the zonal position. Moreover, a lead–lag correlation between the EKE and North Pacific storm track variations exists. The strength of the EKE exhibits a 3–4 year lag positive （negative） correlation with the EOF1 and EOF3 （EOF2） of the North Pacific storm track, while the opposite is true for the position of the EKE. This can arise from the westward propagation of sea surface height anomalies, driven by Atmospheric Teleconnection Patterns associated with the North Pacific storm track.