Shelf and Bottom Water Formation Near East Antarctic Polynyas and Glaciers

9909374费尔班克斯这项研究将调查相对温暖的环极深水周期性冲刷对南极大陆架致密水团形成的影响，以及暖水CNA的入侵是否提高了南极致密水的形成速度。这项研究涉及观察南极东部阿德利海岸外大陆架的水团变化过程，该大陆架位于默茨冰川和尼尼斯冰川舌附近的准永久开放水域附近--即所谓的默茨冰舌。由强大的近海风形成的南极沿海冰川通常被称为主要的海冰和盐分“工厂”，因为新形成的冰被吹向海洋，使得沿海形成更多的冰，而且冰冻过程增加了大陆架水的盐度。薄冰，甚至是开阔的水域，意味着从海洋到大气的大量热量损失，这也增加了大陆架水的密度。陆架水下沉，填满底部的任何凹陷，并在重力的作用下沿着大陆斜坡下沉。为这项研究确定了另一个过程，预计该过程将在这一领域发挥作用：相对温暖的水侵入大陆架，凌驾于大陆架水之上，基本上关闭了致密过程。这项研究将利用RVIB纳撒尼尔·B·帕尔默在南半球夏季获取沿乔治五世海岸的大陆架和斜坡上密集分布的水文站。这里获得的数据将补充澳大利亚国家南极计划的一项类似的冬季研究。

9909374FairbanksThis study will investigate how the formation of dense water masses on the antarctic continental shelves is affected by the periodic flushing by relatively warm circumpolar deep water, and whether the intrusion of warm water cna enhance the rate of formation of dense antarctic water. The study involves the observation of water mass modification processes on the continental shelf off the Adelie Coast in East Antarctica, near a quasi-permanent area of open water in the vicinity of the Mertz and Ninnis Glacier tongues - the so-called Mertz polynya.Antarctic coastal polynyas, formed by strong offshore winds, are often referred to as major sea ice and salt "factories" because the newly formed ice is blown seaward, allowing more ice to be formed along the coast, and because the freezing process increases the salinity of the continental shelf water. The thin ice, or even open water, implies significant heat losses from the ocean to the atmosphere, which also increases the density of the shelf water. The shelf water sinks, fills any depressions in the bottom, and is gravitationally driven down the continental slope. An additional process is identified for this study and is expected to be at work in this area: the intrusion of relatively warm water onto the continental shelf, overriding the shelf water and essentially shutting down the densification processes. The study will make use of the RVIB Nathaniel B. Palmer to obtain a closely spaced array of hydrographic stations over the continental shelf and slope along the George V Coast in the austral summer. The dat obtained here will complement a similar winter study by the Australian National Antarctic Program.***