利用黑潮延伸体海域海平面异常（SLA）数据和SODA海流资料，分析海平面和海流的年际变化特征，以及两者之间的关系。分析发现黑潮延伸体SLA的第二模态是黑潮大弯曲模态，存在29个月的准两年显著振荡。该海域海平面具有显著的年际变化，且与ENSO和PDO密切相关，2002-2004年的黑潮大弯曲期间，海平面与Nino3指数的相关系数为0.74。海平面年际变化和海流关系密切，黑潮延伸体主轴两侧海平面具有显著的季节和年际变化，急流呈大弯曲路径（1993-1996、2002-2004）时，流轴稳定流速大，流轴影响深，急流主轴南侧海平面较高，达到年际变化的最大值，主轴两侧海面高度梯度大。非弯曲期间，急流主轴南压，海流强度减弱，此期间海平面低，主轴两侧海面高度梯度较小。黑潮延伸体上游区海平面变化受黑潮大弯曲影响更为显著。上下游区的海平面和比容海平面的年际变化较为相似，黑潮延伸体海域海流和比容效应共同调控该区域海平面变化。%Sea level variation and its relationship with the Kuroshio current were analyzed by of using the AVISO altimeter data and SODA current data, in representative regional area, Kuroshio Extension (KE) . The second Empirical Orthogonal Functions ( EOF) of the sea level variation in the KE area represented a Kuroshio meander mode with a quasi-biannual period of 29 months. The inter-annual sea level variation related to the El Niño and Kuroshio current closely. The correlation coefficient between inter-annual sea level variation and El Niño was 0.74 during years of 2002-2004 when Kuroshi current was in well-advanced meander. In well-advanced meander years (1993-1996、 2002-2004) , sea level was higher in the south of KE path, and sea level difference between the two sides of KE jet was larger. During no-meander periods, sea level was lower and sea level difference on both sides of jet was small. Sea level variation of up-stream area was affected more significantly by Kuroshio meander than that of down-stream area. Inter-annual variation of the T/P sea level and steric sea level varied similarly in the up and down-stream areas. The Kuroshio extension sea currents and steric effect controlled the regional sea level changes.
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