| 摘要: |
| 南大洋印度洋与太平洋扇区转换带（140°E–180°E，40°S–65°S）是南极绕极流（ACC）与复杂地形相互作用的关键区域，其中尺度涡旋活动对经向物质与能量输送具有重要影响。为系统揭示该区域涡旋的分布特征、跨锋运动及其水文效应，研究利用2000–2022年多卫星高度计融合数据对涡旋进行识别与追踪，并结合Argo剖面对涡旋内部水文开展解析。结果表明：该区域涡动能（EKE）高值区集中在ACC流域显著地形下游，呈双核分布。EKE整体呈增强趋势（1.20±0.72 cm2/s2 yr?1），其在150°E–160°E的增强核心区域速率到达区域平均的10倍以上。气旋式涡旋的强度普遍高于反气旋式涡旋，表现为在振幅、旋转速度、非线性特征、罗斯贝数和平均EKE的高值部分占比更多。跨锋面涡旋呈现显著的极性-方向耦合特征，即北向的气旋式涡旋与南向的反气旋式涡旋分别主导南北向的经向输送，且前者EKE明显高于后者。这两类涡旋的EKE均呈显著增强趋势，速率分别为4.21 ± 3.11) cm2/s2 yr?1与(2.81 ± 2.03) cm2/s2 yr?1。不同极性涡旋携带特征源区水团穿越锋面，有效缓解不同锋面间的温盐和有效势能差异。该研究揭示了复杂地形调制下局地涡旋活动强度变化、跨锋面涡旋的动力分选规律及水文特性再分配能力，为深入理解南大洋经向交换过程及其气候效应提供重要参考。 |
| 关键词: 坎贝尔高原 涡动能 跨锋面涡旋 温盐特征 |
| DOI：10.11693/hyhz20260200035 |
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| 基金项目: |
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| Characteristics of mesoscale eddies and their cross-frontal behaviors near the Campbell Plateau of the Southern Ocean |
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Wang Huimin,Cheng Lingqiao,Lin Dongming,Zuo Juncheng
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1.College of Oceanography and Ecological Science,Shanghai Ocean University;2.College of Marine Living Resource Sciences and Management,Shanghai Ocean University
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| Abstract: |
| The transition zone between the Indian and Pacific sectors of the Southern Ocean (140°E–180°E, 40°S–65°S) is a key region where the Antarctic Circumpolar Current (ACC) interacts with complex topography, and mesoscale eddy activity plays a significant role in meridional material and energy transport. To systematically reveal the distribution characteristics, cross-frontal movement, and hydrographic effects of eddies in this area, the study utilized multi-satellite altimeter-merged data from 2000 to 2022 to identify and track eddies, combined with Argo profiles to analyze the internal hydrographic structure of the eddies. The results show that the high eddy kinetic energy (EKE) areas in this region are concentrated downstream of significant topographic features within the ACC region, exhibiting a dual-core distribution. The overall EKE shows an increasing trend (1.20 ± 0.72 cm2/s2 yr?1), with the core enhancement area in 150°E–160°E reaching more than 10 times the regional average rate. Cyclonic eddies are generally stronger than anticyclonic eddies, as indicated by larger proportions in higher amplitude, rotational speed, nonlinear characteristics, Rossby number, and EKE values. Cross-frontal eddies exhibit a significant polarity-direction coupling feature, with northward-moving cyclonic eddies and southward-moving anticyclonic eddies dominating the meridional transport. The EKE of the former is notably higher than that of the latter. Both types of eddies show significant increasing trends in EKE, with rates of (4.21 ± 3.11) cm2/s2 yr?1 and (2.81 ± 2.03) cm2/s2 yr?1, respectively. Eddies of different polarities carry water masses with characteristic source properties across frontal zones, effectively mitigating the differences in temperature, salinity, and available potential energy between different fronts. This study reveals the variations in local eddy activity intensity modulated by complex topography, the dynamic sorting of cross-frontal eddies, and their capacity for redistributing hydrographic properties, providing important insights for understanding meridional exchange processes in the Southern Ocean and their climatic effects. |
| Key words: Campbell Plateau Eddy kinetic energy Cross-frontal eddies Hydrographic characteristics |