Abstract The last glacial period (116–11.7 ka BP) was an interval characterized by a sequence of abrupt millennial-scale events well documented in Greenland and Antarctica ice-cores. Throughout this period, Greenland cold stadials were accompanied by warm conditions in the thermocline to intermediate waters of the Atlantic Ocean that may have played a role in both the basal melting of ice shelves and the rapid atmospheric warming during the onset of warm interstadials. Climate model simulations indicated an accentuated response of the subtropical western South Atlantic thermocline to the disturbances in the Atlantic circulation. Such works encourage investigations upon thermocline/deep-dwelling planktic foraminifera in this region; however, a study with this aim was not performed. Here we present a paleoceanographic reconstruction from the subtropical western South Atlantic based on the thermocline planktic foraminifera Globorotalia inflata. Our high-resolution δ18O record for the last glacial period presents a millennial-scale variability that strongly resembles the structure of the Greenland Dansgaard-Oeschger cycles during Marine Isotope Stage (MIS) 5. During MIS 3, this millennial-scale variability is absent or considerably dampened. Mg/Ca-derived temperature and seawater δ18O corrected for ice-volume for the MIS 5 interval demonstrate that the region was warmer and saltier (colder and fresher) during early-glacial stadials (interstadials). Our data suggest a reorganization of the northward heat transport throughout the last glacial, in which regions as far south as 24 °S acted as heat reservoirs in periods of weakened Atlantic Meridional Overturning Circulation during MIS 5 but not necessarily (or only marginally) during MIS 3.

中文翻译：

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南大西洋西部副热带温跃层对海洋同位素第 5 和第 3 阶段 Dansgaard-Oeschger 事件的不对称响应

摘要 最后一个冰川期（116-11.7 ka BP）是一个以一系列在格陵兰岛和南极洲冰芯中得到充分记录的千禧年规模的突然事件为特征的间隔。在此期间，格陵兰冷场伴随着温跃层到大西洋中间水域的温暖条件，这可能在冰架的基础融化和暖场间期开始期间的快速大气变暖中发挥了作用。气候模型模拟表明南大西洋西部亚热带温跃层对大西洋环流扰动的反应加剧。此类工作鼓励对该地区的温跃层/深居浮游有孔虫进行调查；然而，没有进行具有此目的的研究。在这里，我们基于温跃层浮游有孔虫 Globorotalia inflata 展示了来自亚热带西南大西洋的古海洋学重建。我们上次冰期的高分辨率 δ18O 记录呈现出千禧年尺度的变化，与海洋同位素阶段 (MIS) 5 期间格陵兰丹斯加德-厄施格循环的结构非常相似。在 MIS 3 期间，这种千年尺度的变化不存在或大大减弱。Mg/Ca 衍生的温度和海水 δ18O 校正了 MIS 5 区间的冰体积表明该地区在早冰期（间期）期间更暖和更咸（更冷和更新鲜）。我们的数据表明，在整个末次冰期，向北的热传输发生了重组，