夏季西北冰洋表层淡水分布的总碱度示踪研究  

SUMMERTIME FRESH WATER FRACTIONS IN THE SURFACE WATER OF THE WESTERN ARCTIC OCEAN EVALUATED FROM TOTAL ALKALINITY

作　　者：高众勇[1] 孙恒[1] 陈立奇[1] 张凡[1] 

机构地区：[1]国家海洋局第三海洋研究所,国家海洋局海洋-大气化学与全球变化重点实验室,福建厦门361005

出　　处：《极地研究》2012年第2期120-128,共9页Chinese Journal of Polar Research

基　　金：国家自然科学基金项目(40976116);福建省杰出青年基金项目(2009J06025);国家海洋局第三海洋研究所基本科研业务费专项资助项目(海三科2010011;海三科2010001);海洋公益性行业科研专项经费项目(201105022);国际极地年中国行动计划项目;中国第三次及第四次北极科学考察项目资助

摘　　要：利用中国第三次和第四次北极科学考察在西北冰洋测定的海水总碱度资料和相关资料,结合海水、海冰融化水及河源淡水3个端元盐度和总碱度的特征值,计算分析了夏季表层海水中淡水所占的比例。示踪研究结果表明,加拿大海盆南部海冰融化水所占比例最大,该区为海冰剧烈融化的冰缘带。径流水的比例明显低于海冰融化水的比例,径流水主要来自白令海入流水中携带的Yukon河水和加拿大Mackenzie河水的输入。2008年夏季海冰融化水以及由白令海入流水输入的淡水量都明显比2010年大,由Mackenzie河水带来的淡水影响变化不大,但其影响的峰值区域位置有所偏移,与海冰分布区相对应。As a quasi-conservative tracer, total alkalinity （TA） can be used to tracethe relative fractions of fresh water and sea water. In this study, based on TA and related data collected during the Third Chinese Arctic Research Ex- pedition （July--September 2008, CHINARE-2008 ） and the Fourth Chinese Arctic Research Expedition （July-- September 2010, CHINARE-2010）, fractions of sea ice meltwater, river runoff and sea water in the surface water of the western Arctic Ocean were determined from salinity and TA relationships. During both surveys, the largest fraction of sea ice meltwater was found around 75°N in the Canada Basin, located at the ice edge. Generally, the fraction of river runoff is less than sea ice meltwater. The river runoff, composed mainly of Yukon River water car- ried by Bering inflow water and Mackenzie River water, was influenced by currents, and there were two areas where its fraction peaked. Our results showed that the dilution effect of fresh water carried by Bering inflow water during CHINARE-2008 might have been stronger than during CHINARE-2010. The area of the peak sea ice meltwater fraction identified during CHINARE-2010 differed from CHINARE-2008, corresponding to different sea ice condi- tions.

关 键 词：西北冰洋 总碱度 淡水分布 海冰融化水 河水 

分 类 号：P343[天文地球—水文科学]