Impact of model resolution for on-shelf heat transport along the West Antarctic Peninsula
Impact of model resolution for on-shelf heat transport along the West Antarctic Peninsula
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DOI：
10.1002/2016jc011875
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发表时间：
2016-10-01
影响因子：
3.6
通讯作者：
Klinck, John M.
中科院分区：
文献类型：
--
作者：
Graham, Jennifer A.;Dinniman, Michael S.;Klinck, John M.
温暖的深水流入南极大陆架对于确定邻近大陆的水体特性起着至关重要的作用。具有两种不同网格分辨率的区域模型已用于模拟西南极半岛沿线的海洋过程。该模型以 4 公里和 1.5 公里的分辨率再现了温暖入侵的位置，与仪表海豹的观测结果进行比较显示。然而，1.5 公里模拟显示了更大的架子热传输，从而改善了架子上热含量的表示。这种热传输的增加与陆架断裂处和近海深海中涡流活动的增加有关。跨架槽是架上热传输的关键部位。比较 Belgica 和 Marguerite 这两个波谷，显示出对分辨率提高的不同反应。在更高的分辨率下，贝尔吉卡海槽的货架运输量有所增加，但玛格丽特海槽的货架运输量没有增加。这可能与这两个地点之间的断架喷气机的不同结构有关。玛格丽特槽热通量的增加归因于货架运输中热含量的增加。外地涡流活动的增加可能会导致更大的横向锋面热传输，从而增加大陆坡上方可用的热量。虽然这些模拟的热传输幅度不同，但都显示出相似的变化模式。风应力的变化会导致架子破裂射流的速度发生变化，从而导致架子上的热传输发生变化。这些结果证明了模型分辨率对于了解南极洲周围跨大陆架运输的重要性。
The flux of warm deep water onto Antarctic continental shelves plays a vital role in determining water mass properties adjacent to the continent. A regional model, with two different grid resolutions, has been used to simulate ocean processes along the West Antarctic Peninsula. At both 4 km and 1.5 km resolution, the model reproduces the locations of warm intrusions, as shown through comparison with observations from instrumented seals. However, the 1.5 km simulation shows greater on-shelf heat transport, leading to improved representation of heat content on the shelf. This increased heat transport is associated with increased eddy activity, both at the shelf-break and in the deep ocean off-shore. Cross-shelf troughs are key locations of on-shelf heat transport. Comparison of two troughs, Belgica and Marguerite, shows differing responses to increased resolution. At higher resolution, there is an increased on-shelf volume transport at Belgica Trough, but not at Marguerite Trough. This is likely related to the differing structure of the shelf-break jet between these two locations. The increased heat flux at Marguerite Trough is attributed to increased heat content in the on-shelf transport. Increased eddy activity off-shelf may lead to greater cross-front heat transport, and therefore increased heat available above the continental slope. While these simulations differ in their magnitude of heat transport, both show similar patterns of variability. Variations in wind stress lead to variations in speed of the shelf-break jet, and therefore on-shelf heat transport. These results demonstrate the importance of model resolution for understanding cross-shelf transport around Antarctica.