Physical Properties and Structural-Stratographic Variations of Frazil, Platlet and Congelation Sea Ice, Ross Sea, Antarctica

南极洲罗斯海冰、片状海冰和凝结海冰的物理性质和结构地层变化

• 批准号: 8915863
• 负责人: Martin Jeffries
• 金额: $ 27.71万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-09-01 至 1994-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8915863&HistoricalAwards=false
• 关键词: Physical; Properties; Structural; Stratographic; Variations

This project is an examination of the mechanical and structural properties of the antarctic ice pack in the Ross Sea, with the goal of defining the geographical variability of various ice types, the deformation processes that are active in the antarctic ice pack, and the large-scale thermodynamics and heat exchange processes of the ice-covered Southern Ocean. Four specific objectives have been defined for this project: (1) A determination of the fraction of frazil, platelet, and congelation ice of the Ross Sea pack ice; (2) an examination of differences in the salinities of these ice types, and a study of whether salinity variations are related to ice structure and stratigraphy; (3) a documentation of grain size and morphology variations in frazil and platelet ice and their relation to salinity differences; and (4) an investigation of the brine exclusion process, and how salt is lost from the sea ice. Differences in ice types are the result of differences in the environment in which the ice forms; frazil ice is formed in supercooled sea water, normally through wind or wave-induced turbulence, while platelet and congelation ice is formed under quiescent conditions. The fraction of frazil ice (which has been observed to be generally in excess of 50% in Weddell Sea ice floes) is an important variable in the energy budget of the upper ocean, and contributes to our understanding of the redistribution of salt, sediment, and micro-organisms in the ocean, and will improve our understanding of microwave and synthetic aperture radar images of sea ice to be obtained form a new generation of polar orbiting satellites.

该项目是对罗斯海南极冰盖的力学和结构特性的研究，目的是确定各种类型冰的地理变异性、南极冰盖中活跃的变形过程以及冰盖覆盖的南大洋的大尺度热力学和热交换过程。为该项目确定了四个具体目标：(1)测定罗斯海浮冰的碎屑冰、碎屑冰和凝结冰的比例；(2)检验这些类型冰的盐度差异，并研究盐度变化是否与冰结构和地层有关；(3)冰晶和片状冰的颗粒大小和形态变化及其与盐度差异的关系的文件；(4)卤水排出过程的调查，以及盐是如何从海冰中流失的。冰类型的不同是形成冰的环境不同的结果；脆性冰是在过冷的海水中形成的，通常是通过风或波浪引起的湍流形成的，而板状和凝结冰是在静止条件下形成的。碎冰的比例(在威德尔海浮冰中普遍超过50%)是上层海洋能量收支的一个重要变量，有助于我们了解海洋中盐、沉积物和微生物的重新分布，并将提高我们对将从新一代极轨卫星获得的微波和合成孔径雷达海冰图像的理解。