南极威德尔海海冰晶体类型分析  

ANALYSIS ON THE CRYSTALS OF SEA ICE CORES DERIVED FROM WEDDELL SEA,ANTARCTICA

作　　者：李志军[1] Nicolaus Marcel Toyota Takenobu Haas Christian 

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,大连116024 [2]Norwegian Polar Institute, 9296 Troms, Norway [3]Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan [4]Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, T6G 2E3, Canada

出　　处：《极地研究》2009年第3期177-185,共9页Chinese Journal of Polar Research

基　　金：国家自然科学基金(40676001);国家科技支撑计划项目(2006BAB18B03);长江学者和创新团队发展计划(IRT042)资助

摘　　要：为了解南极威德尔海不同区域海冰形成过程,分析了2006年9—10月威德尔海海冰调查中的27支冰芯晶体并描述了冰芯反映的冰层形成过程;给出2支完整冰芯晶体照片和多边形晶体雪冰照片,以及对应照片的冰层描述和冰盐度、密度、粒径。根据冰芯晶体揭示的海冰形成过程,发现尽管现场考察均选择较大表面平整的浮冰作业,但冰芯晶体揭示出实际冰层可以是受动力和热力联合作用形成的重叠冰、固结冰脊、二年冰;而从表面到底面属于纯热力学生长形成的冰层所占比例较小。积雪经过密实和水分参与,再冻结形成多边形晶体雪冰也是南极海冰主要组成之一。粒状晶体、过渡区混合晶体和柱状晶体海冰分别占27支冰芯总长度的28.7%、14.4%和55.2%。海冰的区域分布表现出海冰边缘区以纯热力学生长的一年冰为主;在冰架前缘,受动力作用形成的重叠冰和固结冰脊的比例增加,并且存在二年冰和多边形晶体雪冰;冰间湖内生长有大面积纯热力学生长的海冰并向外输送。In order to understand the sea ice forming processes in different areas in Weddell Sea, 27 ice cores were taken from Weddell Sea, Antarctica during September and October, 2006. Their crystals are analyzed, and their ice forming processes are described based on the crystals. The crystal photos of two ice cores from ice surface to bottom, and polygonal granular superimposed ice were given, and their corresponding stratigraphy descriptions and vertical profiles of salinity, density and mean grain size are shown in figures. Based on the ice forming processes from ice core textures, the findings are that although the large smooth ice floes are selected to be as ice investigation sites, the ice sheet at the sampling position may be rafted ice, consolidated ice ridges, second year ice which were affected by dynamic and thermal process together subsequently; the ice from pure thermal growth is few. The polygonal granular superimposed ice from refrozen wetted dense snow is one type of the ice in Antarctica. The granular, granular-columnar mixture and columnar crystals in sea ice are occupied 28.7%, 14.4% and 55.2% respectively over the 27 ice cores. The sea ice forming processes in different areas are that the pure thermal growth ice is predominantly in marginal sea ice zone; the rafted ice and consolidated ice ridges, even second year ice, polygonal granular superimposed ice from dynamic and ther- mal effects are found in front of Larsen A ; there is pure thermal growth ice in polynyas of Larsen A and the ice is transferred outwards.

关 键 词：南极 海冰 晶体 盐度 密度 

分 类 号：P731.15[天文地球—海洋科学]