Collaborative Research: Isotope Stage 3 Climate Change in the Western North Atlantic

这项建议寻求从布莱克-巴哈马外脊岩心深度断面的数据支持对海洋同位素阶段3(~25至65ka)期间千年尺度气候事件的研究。该项目有两个主要目标：(1)通过在有限的地理区域内绘制深度剖面，测试第三阶段事件的古水文变化模型；(2)调查百慕大隆起第三阶段时间序列中十年至百年尺度气候变化的证据。第一个目标将测试这个模型，即大量的冰山排放，即众所周知的海因里希事件，减少了北大西洋深水的浅水和深水成分的产生，而更典型的稳定事件只抑制了深水成分。第二个目标将调查百慕大海隆浮游有孔虫中存在高频氧同位素振荡的证据。为了把这些结果放在气候的背景下，我们将为开放海洋的第三阶段开发可能的最佳年龄模型，并将我们的新数据与现有的基于烯酮的温度序列和深海通风变化的地球化学指标进行比较。

This proposal seeks support for a study of millennial scale climate events during marine isotope Stage 3 (~25 to 65 ka) from data in a depth transect of cores from the Blake-Bahama Outer Ridges. The project has two main objectives: (1) to test models of paleohydrographic change for Stage 3 events by making depth profiles in a limited geographic area, and (2) to investigate evidence for decade to century scale climate change in a Stage 3 time series from the Bermuda Rise. The first objective will test the model that massive discharges of icebergs, known as Heinrich events reduced production of both shallow and deep components of North Atlantic Deep Water, whereas more typical stadial events suppressed only the deep component. The second objective will investigate evidence for high-frequency oxygen isotopic oscillations in planktonic foraminifer from the Bermuda Rise. To put these results in a climatic context, we will develop the best possible age model for Stage 3 in the open ocean, and compare our new data to both existing alkenone-based temperature series and geochemical proxies for deep ocean ventilation changes.