The period from 1976 to 2024 is divided into three subperiods using 1997 and 2017 as dividing points. This study aims to (1) quantify the relative importance of local wind forcing versus wind forcing over the central and eastern North Pacific in regulating Kuroshio Extension (KE) variability during different periods; (2) elucidate the causes of the interperiod differences in the dominant wind-forcing regimes; and (3) clarify the contribution of local wind forcing to the recent extreme northward shift of the KE since 2017. Based on a 1.5-layer reduced-gravity model, the results indicate that the dominant wind forcing regulating decadal KE variability is local wind forcing during 1976–1997, wind forcing over the central and eastern North Pacific during 1998–2016, and local wind forcing again during 2017–2024. Further analyses reveal that the leading modes of North Pacific variability during these three periods correspond to the PDO, the NPGO, and a new mode related to CP ENSO that exhibits pronounced positive anomalies over the KE region, respectively. Differences in the spatial structures of oceanic and atmospheric forcing associated with these modes lead to distinct dominant wind-forcing regions controlling KE variability. For the extreme northward shift of the KE since 2017, our results suggest that CP ENSO–related anomalous warming in the KE region, together with intensified westerlies north of the KE, induces anomalous southward Ekman transport north of the KE. This process results in enhanced convergence and accumulation of water masses on the northern flank of the KE, thereby sustaining its persistent northward displacement. In contrast, during 1976–1997, Ekman meridional transport driven by local wind forcing  is concentrated primarily on the southern flank and is characterized by southward transport. Under the NPGO regime, however, KE variability is mainly controlled by wind forcing over the eastern North Pacific. 
 

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