The Role of Tides in Ocean-Ice Shelf Interactions in the Southwestern Weddell Sea
The Role of Tides in Ocean-Ice Shelf Interactions in the Southwestern Weddell Sea
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DOI：
10.1029/2019jc015847
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发表时间：
2020-06-01
影响因子：
3.6
通讯作者：
Hattermann, T.
中科院分区：
文献类型：
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作者：
Hausmann, U.;Sallee, J. B.;Hattermann, T.
为了研究潮汐在威德尔海海洋-冰架融化相互作用中的作用，以及由此产生的海洋性质和海冰相互作用的后果，我们发展了一个区域海洋-海冰模式配置，该模式具有时变海洋边界和大气强迫，包括深海开放海洋（水平分辨率2.5-4公里），西南大陆架（约2.5公里），以及邻近的洞东部威德尔，拉森和Filchner-Ronne冰架（FRIS，1.5-2.5公里）。模拟环流，水团，冰架融化性能比较整体以及可用的开放海洋和空腔观测知识。潮汐显示，以提高与冰架接触的随时间变化的流动的动能，从而增加融化。这种动态驱动的潮汐净融化的影响，几乎90%的补偿冷却通过融化的水，生产，但不迅速出口的融化区域在威德尔海冷腔制度。由此产生的系统性潮汐驱动增强的融水及其在上升分支上的再冻结，特别是FRIS，空腔环流的作用是增加净冰架融化（相对于没有潮汐的状态增加50%，约为50 Gt yr（-1））。此外，潮汐还增加了熔体诱导的FRIS空腔环流，以及FRIS外流的融水输出。模拟表明，西南大陆架的开阔洋也发生了相应的变化，其特点是整体淡化和全年海冰小型增厚，威德尔海西南部深海也发生了相应的变化，新形成的底层沃茨明显淡化。
To investigate the role of tides in Weddell Sea ocean-ice shelf melt interactions, and resulting consequences for ocean properties and sea ice interactions, we develop a regional ocean-sea ice model configuration, with time-varying ocean boundary and atmospheric forcing, including the deep open ocean (at 2.5-4 km horizontal resolution), the southwestern continental shelf (approximate to 2.5 km), and the adjacent cavities of eastern Weddell, Larsen, and Filchner-Ronne ice shelves (FRIS, 1.5-2.5 km). Simulated circulation, water mass, and ice shelf melt properties compare overall well with available open ocean and cavity observational knowledge. Tides are shown to enhance the kinetic energy of the time-varying flow in contact with the ice shelves, thereby increasing melt. This dynamically driven impact of tides on net melting is to almost 90% compensated by cooling through the meltwater that is produced but not quickly exported from regions of melting in the Weddell Sea cold-cavity regime. The resulting systematic tide-driven enhancement of both produced meltwater and its refreezing on ascending branches of, especially the FRIS, cavity circulation acts to increase net ice shelf melting (by 50% in respect to the state without tides, approximate to 50 Gt yr(-1)). In addition, tides also increase the melt-induced FRIS cavity circulation, and the meltwater export by the FRIS outflow. Simulations suggest attendant changes on the open-ocean southwestern continental shelf, characterized by overall freshening and small year-round sea ice thickening, as well as in the deep southwestern Weddell Sea in the form of a marked freshening of newly formed bottom waters.