In order to monitor the evolution of the British-Irish Ice Sheet (BIIS) and its influence in surface ocean structure during marine isotopic stages (MIS) 2 and 3, we have analyzed the sediments recovered in core MD04-2829CQ (Rosemary Bank, north Rockall Trough, northeast Atlantic) dated between ～41 and ～18 ka B.P. Ice-rafted debris flux and composition, ~(40)Ar/ ~(39)Ar ages of individual hornblende grains, multispecies planktonic stable isotope records, planktonic foraminifera assemblage data and faunal-based sea surface temperatures (SSTs) demonstrate a close interaction between BIIS dynamics and surface ocean structure and water properties in this region. The core location lies beneath the North Atlantic Current (NAC) and is ideal for monitoring the shifts in the position of its associated oceanic fronts, as recorded by faunal changes. These data reveal a succession of BIIS-sourced iceberg calving events related to low SST, usually synchronous with dramatic changes in the composition of the planktonic foraminifera assemblage and with variations in the stable isotope records of the taxa Neogloboquadrina pachyderma (sinistral coiling) and Globigerina bulloides. The pacing of the calving events, from typically Dansgaard-Oeschger millennial timescales during late MIS 3 to multicentennial cyclicity from ～28 ka B.P., represents the build-up of the BIIS and its growing instability toward Heinrich Event (HE) 2 and the Last Glacial Maximum. Our data confirm the strong coupling between BIIS instabilities and the temperature and salinity of surface waters in the adjacent northeast Atlantic and demonstrate the BIIS's ability to modify the NAC on its flow toward the Nordic Seas. In contrast, subsurface water masses were less affected except during the Greenland stadials that contain HEs, when most intense water column reorganizations occurred simultaneously with the deposition of cream-colored carbonate sourced from the Laurentide Ice Sheet.
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机译：为了监测在海洋同位素阶段（MIS）2和3期间英-爱尔兰冰盖（BIIS）的演变及其对表层海洋结构的影响，我们分析了MD04-2829CQ核心（北罗斯玛丽银行）中回收的沉积物Rockall槽，东北大西洋），日期介于〜41和〜18 ka BP之间浮冰碎片通量和组成，单个角闪石颗粒的〜（40）Ar /〜（39）Ar年龄，多物种浮游稳定同位素记录，浮游有孔虫组合数据以及基于动物的海面温度（SST）表明了两者之间的密切相互作用该区域的BIIS动态，地表海洋结构和水属性。核心位置位于北大西洋海流（NAC）下方，非常适合监测动物群变化记录的与其相关的海锋位置的变化。这些数据揭示了由BIIS引起的一系列与低SST相关的冰山崩裂事件，通常与浮游有孔虫组合物的组成发生巨大变化，以及类群新球藻（Neogloboquadrina pachyderma）（正弦卷曲）和Globigerina Bulloides的稳定同位素记录不同。 。产犊事件的节奏，从典型的MIS 3后期的Dansgaard-Oeschger千禧年尺度到〜28 ka BP的百年周期，代表了BIIS的建立及其对Heinrich事件（HE）2和最后冰川的不稳定性的增长。最大值。我们的数据证实了BIIS的不稳定性与邻近的东北大西洋地表水的温度和盐度之间的强耦合，并证明了BIIS能够改变NAC向北欧海流时的NAC。相比之下，除了格陵兰岛含HEs的地表期间，地下水团受到的影响较小，此时最强烈的水柱重组与来自Laurentide Ice Sheet的米黄色碳酸盐的沉积同时发生。
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