2001-2002年间南极埃默里冰架水的空间分布与季节变化

Spatial distribution and seasonal variation of ice shelf water between 2001 and 2002 at Amery Ice Shelf, Antarctica

摘要:

南极冰架水是由海洋—冰架相互作用形成的位温低于局地冰点的水团，较周围水体相对低温、低盐，是衡量冰架物质平衡的良好指示剂。基于澳大利亚埃默里冰架海洋研究计划（AMISOR）2001至2002年的现场观测资料，本文开展了埃默里冰架水空间分布的季节变化与输运特性研究。CTD结果显示，冰架水夏季普遍分布在冰架前缘的西部、中部和东部海域，但中、西部海域的冰架水核心温度更低、分布范围更广。锚碇潜标结果显示，冰架水的分布存在显著的季节变化：冬季，冰架水盘踞在冰架前缘71.0°E以西海域和71.5-72.5°E的中部海域，以流出为主要特征；夏季，除了冰架前缘71.5-72.5°E的中部海域仍被冰架水控制，冰架水还出现在冰架前缘73.5°E以东海域，并以流入为主要特征。而冰架水在冰架前缘西部海域的出流强度明显大于东部海域的入流强度，全年冰架水主要从冰架底部输出进入普里兹湾占主导。

Abstract:

The Antarctic Ice Shelf Water is generated by the ocean-ice shelf interaction and its temperature is lower than the freezing point. Compared with the surrounding water, it is relatively colder and saltier. Thus it can be a good indicator to estimate the mass balance of Amery Ice Shelf. Based on the observation by the Australian Amery Ice Shelf Ocean Research (AMISOR) from 2001 to 2002, the seasonal variation and Sverdrup transport of Ice Shelf Water at Amery Ice Shelf were expounded. The CTD results showed that the ice shelf water is generally distributed in the western, central and eastern front edges of the Amery Ice Shelf in summer, and the water in the western part was more intense and widespread. From the observations of the mooring buoy, it is known that the spatial distribution of ice shelf water presents remarkable seasonal variation. In winter, ice shelf water is mainly distributed to the west of 71.0°E as well as between 71.5°E and 72.5°E of the Amery Ice Shelf with the principal character of outflow. In summer, in spite of the area between 71.5°E and 72.5°E is still occupied by the ice shelf water, it is also distributed to the east of 73.5°E of the Amery Ice Shelf with the principal character of inflow. Compared with the inflow to the east of Amery Ice Shelf, the outflow from the west of Amery Ice Shelf is much stronger. Thus, the ice shelf water is dominated by discharging from the bottom of Amery Ice Shelf to the Prydz Bay throughout the year.