Using Foraminiferal Nd Isotope Records to Test the Paradigm for Deglacial Atlantic Deepwater Variability

利用有孔虫 Nd 同位素记录测试冰消期大西洋深水变化的范式

• 批准号: 1335191
• 负责人: Delia Oppo
• 金额: $ 40万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1335191&HistoricalAwards=false
• 关键词: Using; Foraminiferal; Nd; Isotope; Records

Deepwater export from the northern North Atlantic to the ocean interior is widely believed to have decreased significantly during cold events of the last deglaciation (Heinrich Event 1 and the Younger Dryas). Motivated by recent debate on the topic, the proposed work will produce a novel reconstruction of Atlantic deglacial circulation based on well-dated records of neodymium isotope composition spanning the last ~25,000 years. These records will be developed from analyses of planktonic foraminifera from three depth transects in the western Atlantic (north, tropical, south). In combination with benthic oxygen and carbon isotope measurements, the neodymium isotope records will be used to 1) constrain potential end-member changes, 2) determine water mass variability in the upper, mid-depth, and deep Atlantic, and 3) evaluate the current paradigm of deglacial deepwater variability. This work will advance the understanding of ocean circulation dynamics related to abrupt climate change. The project will support cross-disciplinary collaboration between a senior scientist and an early-career investigator at Woods Hole Oceanographic Institution. Undergraduate and high school students will be trained in laboratory techniques. In addition, ten high school students from diverse backgrounds will be engaged through a one-week internship facilitated by the PI in collaboration with a local high school teacher.

从北大西洋北方到海洋内部的深水输出被广泛认为在最后一次冰消期的寒冷事件（海因里希事件1和新仙女木事件）期间显著减少。受最近关于这一主题的辩论的启发，拟议中的工作将根据过去25,000年钕同位素组成的日期明确的记录，对大西洋冰消环流进行新的重建。这些记录将根据对西大西洋三个深度断面（北、热带、南）的浮游有孔虫的分析得出。结合海底氧和碳同位素测量，钕同位素记录将用于1）限制潜在的端元变化，2）确定大西洋上层、中层和深层的水团变化，3）评估冰消期深水变化的当前范例。这项工作将促进对与气候突变有关的海洋环流动力学的了解。该项目将支持伍兹霍尔海洋研究所的一名资深科学家和一名早期职业调查员之间的跨学科合作。本科生和高中生将接受实验室技术培训。此外，来自不同背景的十名高中生将通过PI与当地高中教师合作提供的为期一周的实习。