Collaborative Research: Radiocarbon content of the Southwest Pacific and Southern Ocean waters in the Holocene and late Quaternary

合作研究：全新世和晚第四纪西南太平洋和南大洋水域的放射性碳含量

• 批准号: 0823487
• 负责人: Elisabeth Sikes
• 金额: $ 29.69万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0823487&HistoricalAwards=false
• 关键词: Collaborative; Research; Radiocarbon; content; Southwest

Intellectual merit: Because changes in ocean circulation have profoundly influenced climate in the past, this project addresses the fundamental role that ocean circulation plays in the regulation of CO2. The work uses radiocarbon in foraminifera tests deposited in sediments off New Zealand to examine how global ocean circulation affects the partitioning of the greenhouse gas CO2 between the ocean and atmosphere. The work has two primary goals: (1) to reconstruct the radiocarbon signature of the glacial Southern Pacific to confirm or refute the presence of a deep water mass old enough to account for the glacial-interglacial changes in atmospheric CO2 and (2) to produce a high resolution record of radiocarbon at various intervals the time of deglaciation to provide a Southern Hemisphere perspective, which is missing from global CO2 and radiocarbon budgets. Ocean circulation can be traced with radiocarbon (14C) because there is a quantifiable difference between the 14C content of atmospheric CO2 gas and that in the ocean where it exists in the form of dissolved carbonate and bicarbonate. In addition, this project takes advantage of the precise stratigraphic control afforded by volcanic ash layers in cored, off-shore sediments from different water depths. Planktonic and benthic foraminiferal pairs will be used to construct vertical profiles of radiocarbon at different depths in the ocean and a time series of oxygen isotope data will be collected to track the evolution of changes in shallow waters (600-2500 m) and deep waters (600-4300m) through the time of the last period of deglaciation (17,500 to 9,500 years ago). Broader impacts: The project includes collaboration between US and New Zealand scientists, student training, and the support of an early career investigator whose gender is under-represented in the sciences.

智力价值：由于海洋环流的变化在过去深刻地影响了气候，因此该项目探讨了海洋环流在二氧化碳调节中发挥的基本作用。 这项工作利用新西兰附近沉积物中沉积的有孔虫测试中的放射性碳来研究全球海洋环流如何影响温室气体二氧化碳在海洋和大气之间的分配。这项工作有两个主要目标：(1) 重建南太平洋冰川的放射性碳特征，以确认或反驳是否存在足够古老的深水团，足以解释大气二氧化碳的冰期-间冰期变化；(2) 产生冰消期不同时间间隔的放射性碳高分辨率记录，以提供南半球的视角，而全球二氧化碳和放射性碳预算中缺少这一点。 海洋环流可以用放射性碳 (14C) 来追踪，因为大气中 CO2 气体的 14C 含量与海洋中以溶解的碳酸盐和碳酸氢盐形式存在的 14C 含量之间存在可量化的差异。此外，该项目利用了来自不同水深的岩心、近海沉积物中的火山灰层所提供的精确地层控制。 将利用浮游和底栖有孔虫对构建海洋不同深度的放射性碳垂直剖面，并收集氧同位素时间序列数据，以跟踪浅水区（600-2500 m）和深水区（600-2500 m）变化的演变。 600-4300m）到末次冰消期（距今17,500年至9,500年）。更广泛的影响：该项目包括美国和新西兰科学家之间的合作、学生培训以及对一名早期职业调查员的支持，该调查员的性别在科学领域代表性不足。