The Kuroshio Extension (KE) is the inertial meandering jet formed by the convergence of the Kuroshio and Oyashio currents in the Northern Pacific. It is widely mentioned in the literature that the KE variability is bimodal on interannual to decadal time scale. The nature of this low frequency variability (LFV) is still under debate; intrinsic oceanic mechanisms are known to play a fundamental role in the phenomenon but there is also evidence from observations that the KE LFV is connected with changes in broader patterns associated with the Pacific Decadal Oscillation, which is in its turn generated by the dominant decadal mode of the sea level pressure variability in the North Pacific. We investigate the respective contributions of oceanic and atmospheric drivers of the KE variability by taking advantage of the OCCIPUT 1/4° global model dataset: it consists in an ensemble of 50 ocean–sea ice hindcasts performed over the period 1960–2015 (hereafter OCCITENS), and in a one-member 330-year climatological simulation (hereafter OCCICLIM). In this context, OCCITENS simulates both the intrinsic and forced variability, while OCCICLIM simulates the "pure" intrinsic variability. We explore several features of the KE, finding analogies between the OCCICLIM and OCCITENS datasets with autonomous and non-autonomous dynamical systems respectively. This approach aims to apply concepts from the dynamical systems theory on complex and realistic ocean simulations. In this framework, the results suggest that both oceanic and atmospheric drivers control the KE LFV, and that the effect of the low-frequency atmospheric forcing reduces the phase space region explored by the system through synchronization mechanisms. The system’s intrinsic variability can be paced, and therefore clustered over the system’s pullback attractor under the effect of the time dependent forcing.

黑潮扩展（KE）是由北太平洋黑潮和御潮潮的汇合形成的惯性曲折射流。在文献中广泛提到，KE的可变性在年际到十年的时间尺度上是双峰的。这种低频可变性（LFV）的性质仍在争论中。众所周知，内在的海洋机制在这一现象中起着基本作用，但从观测中也发现，KE LFV与太平洋年代际振荡相关的更广泛模式的变化有关，而太平洋年代际振荡又是由太平洋年代际占主导地位的年代模式产生的。北太平洋海平面压力的变化。我们通过利用OCCIPUT 1/4°全局模型数据集来研究KE变异性的海洋和大气驱动因素的各自贡献：它包括1960-2015年期间进行的50次海冰后预报的合奏（以下称OCCITENS），以及单成员330年的气候模拟（以下称OCCICLIM）。在这种情况下，OCCITENS模拟内在和强制可变性，而OCCICLIM模拟“纯”内在可变性。我们探索了KE的几个特征，分别找到了具有自主和非自主动力系统的OCCICLIM和OCCITENS数据集之间的类比。这种方法旨在将动力学系统理论中的概念应用到复杂而逼真的海洋模拟中。在此框架下，结果表明，海洋和大气驱动因素都可以控制KE LFV，低频大气强迫的影响通过同步机制减小了系统探索的相空间区域。系统的固有可变性可以调整，因此可以在依赖时间的强迫作用下聚集在系统的回拉吸引子上。