Oelerich Ria, Heywood Karen J, Damerell Gillian M, Thompson Andrew F
Centre for Ocean and Atmospheric Sciences School of Environmental Sciences University of East Anglia Norwich UK.
Environmental Science and Engineering California Institute of Technology Pasadena CA USA.
J Geophys Res Oceans. 2022 Nov;127(11):e2022JC018636. doi: 10.1029/2022JC018636. Epub 2022 Nov 8.
The Bellingshausen Sea hosts heat transport onto the continental shelf, potentially enhancing ice shelf basal melt. Here, we use the GLORYS12V1 1993-2018 reanalysis to identify physical processes that set seasonal and interannual variability of water mass properties in the Eltanin and Latady Bays on the southern Bellingshausen Sea continental shelf. Annual means of potential temperature from 300 m to the seabed reveal interannual variability and allow separation into warm and cold regimes. The Amundsen Sea Low (ASL) is more intense and extends further east during the warm regime than the cold regime. In the warm regime, a wind-induced reduction of sea ice concentration near the coast increases surface heat loss, convection, and formation of cold dense water in winter, associated with a decrease in heat content of the southern Bellingshausen Sea over time and a net northward heat transport. In contrast, in the cold regime, increased sea ice concentration reduces surface heat loss and thus formation of cold, dense water. Combined with an increase in heat content over time and a net southward heat transport, this results in a warming of the southern Bellingshausen Sea. This suggests that variability in the deep water temperature in the southern Bellingshausen Sea is primarily due to local surface heat fluxes above the shelf. The variability of surface heat fluxes is related to the variability of the ASL and its influence on sea ice extent and local formation of cold, dense water in winter.
别林斯高晋海存在热量向大陆架的输送，这可能会增强冰架底部的融化。在此，我们利用1993 - 2018年GLORYS12V1再分析资料，来确定在别林斯高晋海南部大陆架的埃尔塔宁湾和拉塔迪湾中，决定水体属性季节和年际变化的物理过程。从300米深度到海底的位温年平均值揭示了年际变化，并可分为暖态和冷态。与冷态相比，在暖态期间，阿蒙森海低气压（ASL）更强且向东延伸得更远。在暖态下，海岸附近由风引起的海冰浓度降低会增加冬季的表面热损失、对流以及冷重水的形成，这与别林斯高晋海南部热含量随时间减少以及向北的净热输送有关。相反，在冷态下，海冰浓度增加会减少表面热损失，从而减少冷重水的形成。再加上热含量随时间增加以及向南的净热输送，这导致别林斯高晋海南部变暖。这表明别林斯高晋海南部深水温度的变化主要是由于大陆架上方的局地表面热通量。表面热通量的变化与阿蒙森海低气压的变化及其对海冰范围以及冬季冷重水局地形成的影响有关。
