The Antarctic Slope Current in a Changing Climate
The Antarctic Slope Current in a Changing Climate
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DOI：
10.1029/2018rg000624
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发表时间：
2018-12
影响因子：
25.2
通讯作者：
A. Thompson;A. Stewart;P. Spence;K. Heywood
中科院分区：
文献类型：
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作者：
A. Thompson;A. Stewart;P. Spence;K. Heywood
南极坡流(ASC)是环抱南极大陆架并调节流向南极海岸线的水流的一种连贯环流特征。ASC的结构和变化影响南极海岸线附近具有全球影响的关键过程，例如南极冰架融化和水团形成，这决定了全球翻转环流的强度。最近的理论、模型和观测进展揭示了ASC的新的动力学性质，这使得现在进行回顾是及时的。早期对ASC的审查主要集中在ASC主要战线的水性质的地方分类上。相反，我们根据控制顺坡环流和横坡环流的动力学机制，对海流的锋面结构进行了分类；这两种环流模式是强耦合的，类似于南极绕极洋流。高度可变的运动，如密集的溢流、潮汐和涡流被证明是跨坡和跨陆架交换的关键组成部分，但由于观测和模拟的限制，对这些过程的分布和强度将如何在变化的气候中演变的理解仍然很差。将ASC与厄尔尼诺等气候变率的较大模式联系起来的结果表明，ASC是全球气候的组成部分。为了准确地模拟和预测未来的南极海冰范围、南极冰盖的稳定性以及南大洋对全球碳循环的贡献，仍然需要改进对ASC的动力学理解。
The Antarctic Slope Current (ASC) is a coherent circulation feature that rings the Antarctic continental shelf and regulates the flow of water toward the Antarctic coastline. The structure and variability of the ASC influences key processes near the Antarctic coastline that have global implications, such as the melting of Antarctic ice shelves and water mass formation that determines the strength of the global overturning circulation. Recent theoretical, modeling, and observational advances have revealed new dynamical properties of the ASC, making it timely to review. Earlier reviews of the ASC focused largely on local classifications of water properties of the ASC's primary front. Here we instead provide a classification of the current's frontal structure based on the dynamical mechanisms that govern both the along‐slope and cross‐slope circulation; these two modes of circulation are strongly coupled, similar to the Antarctic Circumpolar Current. Highly variable motions, such as dense overflows, tides, and eddies are shown to be critical components of cross‐slope and cross‐shelf exchange, but understanding of how the distribution and intensity of these processes will evolve in a changing climate remains poor due to observational and modeling limitations. Results linking the ASC to larger modes of climate variability, such as El Niño, show that the ASC is an integral part of global climate. An improved dynamical understanding of the ASC is still needed to accurately model and predict future Antarctic sea ice extent, the stability of the Antarctic ice sheets, and the Southern Ocean's contribution to the global carbon cycle.