Variability in surface currents is mainly induced by the time-varying wind forcing. Recent studies have revealed robust pronounced changes in the atmospheric circulation over the Pacific came with the Pacific Decadal Oscillation (PDO). However, the PDO is a climate index based on sea surface temperature (SST) variations, and may not be appropriately considered as a climate forcing. Here, we suggest the Atlantic SST variability is the ultimate forcing leading to changes in the atmospheric circulation and surface winds over the North Pacific. Anomalous warm North Atlantic and cold South Atlantic leads to weak Hadley cell in the Northern Hemisphere, resulting in a northward displacement of the ITCZ as well as a positive wind stress curl anomaly in the Pacific subtropical region, which would reduce the North Pacific subtropical gyre (NPSG). Associated with reduced sea surface height in the subtropics by the weakened NPSG, the North Equatorial Current (NEC) is weakened based on geostrophy. Changes in basin-scale winds further result in the southward migration of the tropical gyre and consequential downstream ocean circulation.

表面电流的变化主要是由时变风强迫引起的。最近的研究表明，太平洋年代际振荡（PDO）伴随着太平洋大气环流的明显变化。但是，PDO是基于海表温度（SST）变化的气候指数，可能无法适当地视为气候强迫。在这里，我们认为大西洋海表温度的变化是导致北太平洋大气环流和地表风变化的最终强迫。异常温暖的北大西洋和寒冷的南大西洋导致北半球的Hadley细胞弱，导致ITCZ向北位移以及太平洋亚热带地区的正风应力卷曲异常，这将减少北太平洋亚热带回旋（ NPSG）。NPSG的减弱与亚热带海表高度的降低有关，北赤道洋流（NEC）则由于地球动力学而减弱。盆地规模风的变化进一步导致热带旋涡向南迁移，进而导致下游海洋环流。