US-France Cooperative Research: Variability in Thermohaline Circulation and North Atlantic Climate

0233483 McManus这一为期三年的美法气候变化合作奖涉及伍兹霍尔海洋研究所和法国国家科学研究中心（CNRS）气候科学与环境实验室的研究人员。 杰瑞·F美国的McManus和法国的Laurent Labeyrie将领导这项合作计划，模拟和分析温盐环流的变化及其对北大西洋气候的影响。 海洋的温盐环流在不同的时间尺度上经历了重组，对了解过去和现在的地球气候具有重要意义。 营养盐代用指标提供了水团重新配置的重要证据。 动态示踪剂可以对深水形成和输出速率的变化进行定量评价，从而为这一信息提供理想的补充。 水团特性和倾覆率的结合可以直接估计海洋温盐环流的运输。 为此，美国和法国的研究人员将改进一种利用两种长寿命铀系列231 Pa和230 Th的方法。 他们将绘制大西洋散装沉积物岩心埋藏率（231 Pa/230 Th）图。 此外，他们还将通过高分辨率时间序列评估环流变化与气候变异之间的联系。 美国集团为此次合作带来了铀系列放射化学领域的专业知识。 此外，法国在空间覆盖和分辨率方面的专业知识以及法国INUS岩心储存库的使用权也是一个补充。该奖项代表了美国方面向NSF和法国国家科学研究中心（CNRS）提出的联合建议。 NSF将支付美国调查人员的差旅费和生活费。 CNRS将支持法国研究人员和一名研究生访问美国。 该项目将促进了解海洋环流对气候变化和北大西洋气候突变的原因和潜在影响。

0233483McManusThis three-year award for US-France collaboration in climate change involves researchers at the Woods Hole Oceanographic Institution and the Laboratory for Climate Sciences and Environment of the French National Center for Scientific Research (CNRS). Jerry F. McManus in the US and Laurent Labeyrie in France will lead this collaborative program to model and analyze the variability in thermohaline circulation and impact on North Atlantic climate. The ocean's thermohaline circulation has undergone reorganization on various time scales, with important implications for understanding the Earth's climate in the past and present. Nutrient proxies provide important evidence of watermass reconfigurations. Dynamical tracers may provide an ideal complement to this information by allowing quantitative evaluation of changes in the rates of deepwater formation and export. Combination of watermass properties and overturning rate could yield direct estimates of the transport by the ocean's thermohaline circulation. To this end, the US and French investigators will refine a method that utilizes two long-lived uranium series, 231 Pa and 230 Th. They will construct maps of the burial ratio (231Pa/230Th) in bulk sediment cores of the Atlantic Ocean. In addition, they will evaluate the link between changes in circulation and climate variability through high-resolution time series. The US group brings to this collaboration expertise in the area of Uranium-series radiochemistry. This is complemented by French expertise in spatial coverage and resolution and access to the IMAGES cores repository in France.This award represents the US side of joint proposals to the NSF and the French National Center for Scientific Research (CNRS). NSF will cover travel funds and living expenses for the US investigators. CNRS will support the visits of the French researchers and a graduate student to the United States. The project will advance understanding of the causes and potential impact of ocean circulation on climate change and abrupt climate change in the North Atlantic.