900ka variability of the North Atlantic deep water mass Nd composition

大西洋子午线翻转环流(AMOC)是全球气候系统中的一个关键因素，因为它在整个半球的物质和热量输送方面做出了巨大的贡献。储存在大西洋深层沉积物的自生部分中的钕同位素已被证明是记录重大和千年气候变化的这种来源变化的宝贵工具。因此，在这个拟议的项目中，我们研究了过去100万年来北大西洋深处的这一水团竞争过程，部分分辨率为千年，以重建深水在众多气候周期中的长期演变。此外，我们打算恢复变化的长期频率，甚至可能从深海沉积物中发现尚未记录的Dansgard/Oeschger事件。后者似乎是可能的，因为先前的一项研究揭示了过去150ka期间深水ND同位素组成与D/O事件之间的强烈联系(Böhm等人，2015年)。选择的地点是ODP172航段1063号站位的深海沉积物岩心，在那里，对铁/锰渗滤液中自生Nd同位素的测量成功地追踪到了与千年气候变化有关的深水来源的变化(Böhm等人，2015年)。此外，我们这个项目的第一个结果揭示了整个管理信息系统11和终止V的一个独特的模式，在这个项目的框架内，我们打算完成和完成开始的工作，以提高记录的时间分辨率。通过该项目建立的记录有可能成为西北大西洋气候和深水来源之间联系的宝贵基准，这将有力地提高我们对海洋气候反馈的理解。

The Atlantic Meridional Overturning Circulation (AMOC) is a key player in the global climate system due to its large contribution regarding matter and heat transport across the hemispheres. Neodymium isotopes stored in the authigenic fraction of deep Atlantic sediments have been proven valuable tools to record such provenance changes across major and millennial climate variations. Therefore, in this proposed project we investigate this process of water mass competition in the deep North Atlantic over the past 1 million years at partly millennial resolution to reconstruct the long term evolution of deep water across numerous climate cycles. Moreover, we intend to retrieve the long term frequency of changes and possibly even discover yet unrecorded Dansgard/Oeschger events from deep sea sediments. The latter seems possible as a previous study has revealed a strong link between deep water Nd isotope composition and D/O events during the past 150ka (Böhm et al., 2015). The site of choice is the deep sea sediment core at ODP Leg 172 Site 1063, where measurements of authigenic Nd isotopes in Fe /Mn -leachates have successfully traced changes of deep water provenance related to millennial climate change (Böhm et al., 2015). Moreover, our first results from this project have revealed a unique pattern across MIS 11 and thus termination V. Within the frame of this project we intend to accomplish and complete the work initiated improving the time resolution of the record. The record established through this project has the potential to become an invaluable benchmark for the link between climate and deep water provenance in the Northwest Atlantic that will strongly improve our understanding of ocean - climate feedbacks.