Kalman Filtering and Smoothing of Sediment Records from the Atlantic Ocean over the last 20 KYRS

过去 20 KYRS 大西洋沉积物记录的卡尔曼过滤和平滑

• 批准号: 1103395
• 负责人: Olivier Marchal
• 金额: $ 43.74万
• 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: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1103395&HistoricalAwards=false
• 关键词: Kalman; Filtering; Smoothing; Sediment; Records

Paleoclimatology is a rapidly evolving field, with a sustained production of records with improved accuracy and chronology. As the number of such records increases, the question of how to interpret them in the presence of a dynamical model has emerged. This work, led by a researcher at the Woods Hole Oceanographic Institution in Massachusetts, develops an inverse method for assimilating long time series of sea surface temperature and other oceanic properties, such as those generated from the analysis of sediment cores, into three-dimensional models of ocean circulation. The computational challenge posed by data assimilation over geologic time scales will be addressed by relying on a model with simplified dynamics and on a partitioned Kalman filter & smoother. The filter & smoother will be applied to drive the model with a collection of sediment records over the last 20,000 years from the North Atlantic Ocean. The movements of large-scale hydrographic fronts and the attendant circulation changes over this time interval will be estimated in a manner that is consistent with both sediment data and ocean dynamics, thereby allowing various paleoceanographic hypotheses to be tested. By estimating the time-dependent state of the North Atlantic Ocean over the last 20,000 years, the project will provide a perspective on ongoing changes in ocean circulation that are postulated from instrumental records. This project brings together an ocean modeler, a paleoceanographer, and two physical oceanographers to ensure a robust approach to the various aspects of the project. These participants include two collaborators from French institutions. Funding supports a graduate student and a post-doctoral scholar at the Woods Hole Oceanographic Institution.

古气候学是一个快速发展的领域，持续生产的记录具有更高的准确性和年表。随着这种记录的数量增加，如何在动力学模型的存在下解释它们的问题已经出现。这项工作由马萨诸塞州的伍兹霍尔海洋研究所的一名研究员领导，开发了一种逆方法，用于将海洋表面温度和其他海洋特性的长时间序列，如沉积物岩心分析产生的序列，同化为海洋环流的三维模型。地质时间尺度上的数据同化所带来的计算挑战，将通过依赖于一个模型与简化的动态和分区卡尔曼滤波平滑。滤波器平滑器将用于驱动模型，收集北大西洋过去20，000年的沉积物记录。在这段时间内，将以与沉积物数据和海洋动力学相一致的方式估计大规模水文锋面的运动和随之而来的环流变化，从而使各种古海洋学假设得到检验。该项目通过估计北大西洋在过去20 000年中随时间变化的状况，将提供一个关于仪器记录假设的海洋环流持续变化的视角。该项目汇集了一名海洋建模师，一名古海洋学家和两名物理海洋学家，以确保对项目的各个方面采取强有力的方法。这些参与者包括来自法国机构的两名合作者。资金支持伍兹霍尔海洋研究所的一名研究生和一名博士后学者。