| 摘要: |
| 黑潮是北太平洋副热带环流系统的一支重要的西边界流。前人对不同流段黑潮的季节和年际变化进行了诸多研究，然而基于不同数据所得结论仍存在差异，尤其是不同模式计算所得流量差别很大，而且以往研究往往着眼于某一流段，对不同流段黑潮变化之间的异同及其原因涉及较少。本文基于卫星高度计数据，评估了OFES（Ocean general circulation model For the Earth Simulator）和HYCOM（Hybrid Coordinate Ocean Model）两个模式对吕宋岛和台湾岛以东黑潮季节与年际变化的模拟能力，进而对两个海域黑潮变化的异同及其物理机制进行了分析。结果表明：HYCOM模式对黑潮季节变化的模拟较好，而OFES模式对黑潮年际变化的模拟较好。吕宋岛以东黑潮和台湾岛以东黑潮在季节与年际尺度上的变化规律均不相同，且受不同动力过程控制。吕宋岛以东黑潮呈现冬春季强而秋季弱的变化规律，主要受北赤道流分叉南北移动的影响；而台湾岛以东黑潮呈现夏季强冬季弱的变化特点，主要受该海区反气旋涡与气旋涡相对数目的季节变化影响。在年际尺度上，吕宋岛以东黑潮与北赤道流分叉及风应力旋度呈负相关，当风应力旋度超前于流量4个月时相关系数达到了-0.56；而台湾岛以东黑潮的流量变化则受制于副热带逆流区涡动能的变化，且滞后于涡动能9个月时达到最大正相关，相关系数为0.44。本研究对于深入理解不同流段黑潮的多尺度变异规律及其对邻近海区环流与气候的影响具有重要意义，同时对于黑潮研究的数值模式选取具有重要参考价值。 |
| 关键词: 黑潮 流量 季节和年际变化 ENSO (El Niño-Southern Oscillation) |
| DOI：10.11693/hyhz20200300062 |
| 分类号:P731 |
| 基金项目:国家自然科学基金，41776021号，41606016号；中科院战略先导专项，XDB42010102号；全球变化与海气相互作用专项，GASI-IPOVAI-01-01；山东省重大科技创新项目，2018SDKJ0105号；山东省自然科学基金，ZR2016DQ04号；鳌山科技创新计划项目，2016ASKJ12。 |
附件 |
|
| COMPARATIVE ANALYSIS OF SEASONAL AND INTERANNUAL VARIATION OF KUROSHIO EAST OF LUZON AND TAIWAN ISLAND |
|
WU Jie1,2, ZHANG Lin-Lin1,3,4, YAN Xiao-Mei1,3,4
|
|
1.Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;2.University of Chinese Academy of Sciences, Beijing 100049, China;3.Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China;4.Pilot National Laboratory for Marine Science and Technology(Qingdao), Qingdao 266237, China
|
| Abstract: |
| The Kuroshio is an important western boundary current of the subtropical gyre in the North Pacific. Previous studies focused on the seasonal and interannual variation of Kuroshio in different areas. However, the conclusions are different due to different datasets, especially different model outputs. Moreover, previous studies often focus on one part of the Kuroshio, and seldom involve the Kuroshio variations in different areas and their causes. Based on satellite altimeter data, we evaluated the simulation of OFES and HYCOM models on the seasonal and interannual variations of the Kuroshio east of Luzon Island and Taiwan Island, and then analyzed the difference of Kuroshio variations in these two regions and their physical mechanism. The results show that HYCOM model is better in simulating the seasonal variation of the Kuroshio, and OFES model is better in simulating the interannual variation of the Kuroshio. Seasonal and interannual variations of the Kuroshio east of Luzon Island and Taiwan Island are different and controlled by different dynamic processes. The Kuroshio east of the Luzon Island is strong in winter/spring and weak in autumn, which is affected mainly by the meridional shift of the North Equatorial Current bifurcation, while the Kuroshio east of Taiwan Island is strong in summer and weak in winter, which is mainly affected by the eddy activity east of Taiwan Island. On the interannual time scale, the Kuroshio east of the Luzon Island exhibits negative correlation with the North Equatorial Current bifurcation and the wind stress curl. When the wind stress curl leads the Kuroshio transport by 4 months, the correlation coefficient reaches -0.56, while the volume transport of the Kuroshio east of Taiwan Island is subject to the variation of eddy kinetic energy (EKE) in the Subtropical Countercurrent region, and their correlation coefficient reaches 0.44 when the transport lags the EKE by 9 months. The results of this study are important for further understanding the multi-scale variability of Kuroshio in different areas and its influence on the circulation and climate in the adjacent waters, and also for the selection of numerical models for Kuroshio research. |
| Key words: Kuroshio volume transport seasonal and interannual variation ENSO (El Niño-Southern Oscillation) |
