Oceanic Response to a Coastal Polynya, Terra Nova Bay, Antarctica

南极洲特拉诺瓦湾沿海冰间湖的海洋反应

• 批准号: 1341688
• 负责人: Christopher Zappa
• 金额: $ 89.85万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1341688&HistoricalAwards=false
• 关键词: Oceanic; Response; Coastal; Polynya; Terra

Antarctic coastal polynas are, at the same time, sea-ice free sites and sea-ice factories. They are open water surface locations where water mass transformation and densification occurs, and where direct atmospheric exchanges with the deep ocean circulation are established. Various models of the formation and persistence of these productive and diverse ocean ecosystems are hampered by the relative lack of in situ meteorological and physical oceanographic observations. This is especially so during the inhospitable conditions of their formation and activity during autumn to winter transition and the polar night. The Western Ross Sea, downstream from two of the largest coastal Antarctic polynyas, happens to be a region where there continues to be net sea-ice production, as indicated by satellite measurements of areal extent, duration and concentration.Characterization of the lower atmosphere properties, air-sea surface heat fluxes and corresponding ocean depth profiles of the Terra Nova Bay (TNB) polynya, is sought for a more detailed understanding of the role of polynyas in the production of latent-heat type sea ice and the formation, through sea ice brine rejection, of dense ocean bottom waters. This observational program will simultaneously identify mechanisms responsible for water mass modification within TNB and document aspects of dense shelf water formation within a large Antarctic polynya system. This study will characterize the water masses within a polyna over the course of an annual cycle using moorings yielding in-situ column and near-surface oceanic observation.

同时，南极沿海的多角体也是无海冰地区和海冰工厂。它们是开放的水面位置，在那里发生水团转化和致密化，并建立与深海环流的直接大气交换。由于相对缺乏现场气象学和物理海洋学观测，关于这些多产和多样的海洋生态系统的形成和持久性的各种模型受到阻碍。尤其是在秋冬过渡期和极夜期间，它们的形成和活动条件恶劣。罗斯海西部位于南极两个最大的沿海冰穴的下游，恰好是一个海冰净生产持续不断的区域，这一点可从卫星对冰穴面积、持续时间和集中度的测量中看出。旨在更详细地了解冰穴在产生潜热型海冰和通过海冰盐水排斥形成稠密海底沃茨方面的作用。这一观测计划将同时确定TNB内水团变化的机制，并记录大型南极冰间湖系统内密集陆架水形成的各个方面。这项研究将利用产生原位柱的系泊装置和近地表海洋观测来确定水穴内水团在一个年循环过程中的特征。