东南极洲Lambert冰川流域西部地区的雪层剖面和积累速率变化特征  

A Study of Snow Stratigraphy and Accumulation-rate Change in the West Part of the Lambert Glacier Basin， East Antarctica

作　　者：任贾文[1] 秦大河[1] 

机构地区：[1]中国科学院兰州冰川冻土研究所

出　　处：《冰川冻土》1995年第3期274-282,共9页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金;中国科学院兰州冰川冻土研究所冰芯实验室资助

摘　　要：近几年在Ｌａｍｂｅｒｔ冰川流域西部地区进行的大量雪芯、雪坑剖面观测表明，雪层的可见层位特征在积累速率较高时保存完好。但由于强烈下降风和微地形的影响，年积累量在短距离内变化较大，一个地点某一年份的积累量须由几个雪层剖面对比才能确定；若用花杆测量只能经几年观测获得其平均值。在积累量较高地点将雪层剖面、δ￣（１８）Ｏ和固体电导率剖面结合起来确定的积累速率序列由早期考察结果得以验证。与其它地区（如ＷｉｌｋｅｓＬａｎｄ和Ｍｉｚｕｈｏ高原）相比，该地区最显著的特点是靠近海岸地带的积累速率很低，这意味着近海水汽和低气流对本区降水量的影响很小。近５０年来积累速率的总趋势是减小，这与报道较多的其它地区近几十年来呈增加趋势明显不同。The Lambert Glacier Basin， over 10~6 km^2 in area，is a particular region because of its dis- tinct topography． A vast amount of stratigraphy observation of firn－core and snow一pit pro-files indicates that the visibale stratigraphic features are preserved well at relatively high accumulation sites． However， due to the effect of strong katabatic wind and microrelie（annualaccumulation varies greatly within a short distance， and as a result， several snow－profiles orseveral－vear stake data are necessarv in detennination of the aeeumulation rate at a site。 Thederived accumulation rate series from comparison of stratigraphy，δ^(18)Oand electric conduc-tivity profiles were verified by the early measurement result at a higher accumulation site。 Bycomparison with other regions （ such as Wilkes Land and Mizuho Plateau）in EastAntarctica，the most remarkable characteristic in this region is that the accumulation of localoceanic vapour and low aircurrent is that the accumulation rate is very low toward the coast，implying that the influence of local oceanic vapour and low aircurrent is not important．Theaeeumulation rate has an overall decrease trend for past 50 years in this region，strikinglycontrasting to the reported increase trend of recent decades for other regions in Antarctica.

关 键 词：冰川 雪层剖面 积累 速率变化 东南极洲 

分 类 号：P343.6[天文地球—水文科学]