Collaborative Research: Pathways of Circumpolar Deep Water to West Antarctica from Profiling Float and Satellite Measurements

当前海洋学对南大洋环极深水（CDW）相对温暖的水向南移动到南极大陆架的寒冷水域时的相互作用的兴趣是基于从全球海洋到大陆冰架底部的热输送的潜在重要性。这对于了解南极大陆的长期物质平衡、巨大的南极冰盖的稳定性以及在全球变暖的情况下海平面上升的速度都是必要的。需要改进关于变暖的CDW如何穿越南极环极流（ACC）的机制的观测知识。这种动力输送被认为是由时变中尺度环流特征的涡流通量发生的，理解它将改进耦合的海洋-大气气候模式。下一代海洋-冰-气候耦合模式的发展有助于我们了解大气热通量、冰川和海冰平衡以及南极生态系统变化的未来变化。我们理解的一个反复出现的障碍是缺乏这个遥远地区的数据。在这个项目中，一些适合在海冰下作业的EM-APEX水下剖面浮标将在澳大利亚夏季期间在太平洋地区进行多达4次的航行。这些浮标将在极锋以南发射，在为期2年的任务中测量2000米深度的切变、湍流、温度和盐度，同时跟踪CDW层。

Current oceanographic interest in the interaction of relatively warm water of the Southern Ocean Circumpolar Deep Water ( CDW) as it moves southward to the frigid waters of the Antarctic continental shelves is based on the potential importance of heat transport from the global ocean to the base of continental ice shelves. This is needed to understand the longer term mass balance of the continent, the stability of the vast Antarctic ice sheets and the rate at which sea-level will rise in a warming world. Improved observational knowledge of the mechanisms of how warming CDW moves across the Antarctic Circumpolar Current (ACC) is needed. Understanding this dynamical transport, believed to take place by the eddy flux of time-varying mesoscale circulation features, will improve coupled ocean-atmospheric climate models. The development of the next generation of coupled ocean-ice- climate models help us understand future changes in atmospheric heat fluxes, glacial and sea-ice balance, and changes in the Antarctic ecosystems. A recurring obstacle to our understanding is the lack of data in this distant region. In this project, a number of subsurface profiling EM-APEX floats adapted to operate under sea ice will be launched on up to 4 cruises of opportunity to the Pacific sector during Austral summer. The floats will be launched south of the Polar Front and measure shear, turbulence, temperature, and salinity to 2000m depth for up to 2 year missions while following the CDW layer.