Radium-226 in the global ocean as a tracer of thermohaline circulation: Synthesizing half a century of observations
Radium-226 in the global ocean as a tracer of thermohaline circulation: Synthesizing half a century of observations
复制标题
全球海洋中的镭 226 作为温盐环流的示踪剂：综合半个世纪的观测结果
DOI：
10.1016/j.earscirev.2022.103956
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发表时间：
2022-02
影响因子：
12.1
通讯作者：
Zhigang Yu
中科院分区：
文献类型：
--
作者：
Bochao Xu;Sanzhong Li;William C. Burnett;Shibin Zhao;Isaac R. Santos;Ergang Lian;Xiaogang Chen;Zhigang Yu
天然存在的镭同位素是海洋过程的强有力的天然示踪剂，支持元素收支的量化。Ra-226是海洋中最丰富的镭同位素，半衰期最长（1600年）。最初，226 Ra被用于了解全球尺度的深海环流，后来被用作海底地下水排放和底栖通量的示踪剂。在这里，我们综合了来自多个国际研究计划（包括GEOSECS，TTO和GEOTRACES）的历史溶解226 Ra数据，以构建全球海洋226 Ra分布的全球图像。全球海洋中~（226）Ra的活度沿着温盐环流路径增加。深水和底层水团被发现与特征226 Ra属性确认226 Ra是一个很好的温盐示踪剂。226 Ra的垂直分布与南极底层水（AABW）沿三大洋（大西洋、印度洋和太平洋）西部边界沿着渗入三大洋的情况一致。北大西洋深层水（NADW）向南流动，主要沿西边界沿着汇入南极绕极流（ACC）。NADW的东部气流分支在进入印度洋时相对较弱。北太平洋深层水（NPDW）主要沿东边界沿着向南输送。东太平洋海隆将NPDW 226 Ra信号分开，然后在南太平洋西部的中间深度（2000米至3000米）与ACC合并。天然示踪剂226 Ra，Si和Ba的组合可以提供对水混合以及这些元素的源/汇行为的额外见解。考虑到226 Ra主要来自底部（沉积物），它补充了广泛使用的自上而下的地球化学示踪剂，如从大气中穿透海洋的14 C。随着在小体积样品中测量226 Ra的能力的提高，226 Ra现在可以更广泛地用作海洋学调查的地球化学示踪剂，以评估深海混合，运输和停留时间
Naturally occurring radium isotopes are powerful natural tracers of marine processes and support the quantification of elemental budgets. Ra-226 is the most abundant radium isotope in the ocean with the longest half-life (1600 years). Initially, 226 Ra was used to understand global scale deep ocean circulation and later was applied as a tracer of submarine groundwater discharge and benthic fluxes . Here, we synthesize historical dissolved 226 Ra data from multiple international research programs including GEOSECS, TTO and GEOTRACES to build a global picture of 226 Ra distribution throughout the global ocean. The activities of 226 Ra in the world's ocean increases along the thermohaline circulation pathways. Deep and bottom water masses are found with characteristic 226 Ra properties confirming that 226 Ra is a good thermohaline tracer. The vertical 226 Ra distribution is consistent with the penetration of the Antarctic Bottom Water (AABW) into all three major oceans (Atlantic, Indian and Pacific) along their western boundaries. The North Atlantic Deep Water (NADW) flows southward and merge into the Antarctic Circumpolar current (ACC) mainly along the western boundary. The eastern flow branch of the NADW is relatively weak as it enters the Indian Ocean. North Pacific Deep Water (NPDW) is transported mostly southward along the eastern boundary. The East Pacific Rise splits the NPDW 226 Ra signal and later merges into the ACC at intermediate depths (2000 m-3000 m) in the western South Pacific. A combination of the natural tracers 226 Ra, Si and Ba can provide additional insights into water mixing as well as source/sink behaviors of these elements. Considering that 226 Ra originates mainly from the bottom (sediments), it complements widely used top-down geochemical tracers such as 14 C that penetrates the ocean from the atmosphere. With improved abilities to measure 226 Ra in small volume samples, 226 Ra can now be more widely applied as a geochemical tracer for oceanographic investigations to assess deep ocean mixing, transport, and residence times
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DOI：
10.1016/s1569-4860(07)00009-5
发表时间：
2008
期刊：
Radioactivity in the Environment
影响因子：
--
作者：
T. Ku;S. Luo
通讯作者：
T. Ku;S. Luo
影响因子：
5.3
作者：
Y. Li;T. Ku;G. Mathieu;K. Wolgemuth
通讯作者：
Y. Li;T. Ku;G. Mathieu;K. Wolgemuth
影响因子：
--
作者：
T. Ku;S. Luo
通讯作者：
T. Ku;S. Luo
影响因子：
5.1
作者：
W. Koeve;H. Wagner;P. Kähler;A. Oschlies
通讯作者：
W. Koeve;H. Wagner;P. Kähler;A. Oschlies
影响因子：
--
作者：
B. Somayajulu;T. Church
通讯作者：
B. Somayajulu;T. Church