Development of Data Assimilation Methods for Mesoscale Processes and General Circulation in the Ocean

海洋中尺度过程和大气环流数据同化方法的发展

• 批准号: 07044050
• 负责人: IKEDA Motoyoshi
• 金额: $ 4.03万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07044050/
• 关键词: physical oceanography; data assimilation; satellite remote sensing; variational method; adjoint equation method; Kalman filter method

1995-96Since data assimilation is a new approach for revealing oceanographic processes, it was extremely useful for the principal investigator (PI) and the co-investigators (CI) to exchange the information that they had among them. Hence, we held a meeting in Tsukuba in July, in which the other researchers were also invited and worked together to review the existing methods and search data sets.The PI visited Canada and did Research on the adjoint equation method taht Russian CI (living in Canada) developed. They visited Japan for one and half months to participate in the PI's projects. They visited many research institutes in Japan and exchanged their knowledge with Japanese scientists. The PI and Russian CI submitted a paper to Journal of Oceanography. One CI (Kamachi) visited Norway to investigate the Kalman filter method. This trip was highly necessary, because there was no specialist in Japan in this field.1996-97Following the first meeting in the first year, we held the second, m … More ore international meeting in Mutsu by inviting five CI from various countries. The total number of the participants wa more than 40. The participants exchanged the information on the more advanced methods of data assimilation than the first year. Some suggestions include (1) in the adjoint method, a dynamical model with a simpler physics may be more suitable as a constraint model, and (2) in the Kalman filter method, it is necessary to remove instability when a strongly nonlinear system is dealt with.The PI visited University of Hawaii to exchange information on data assimilation for general circulation in the North Pacific.Outcomes from this projects are(1) it is possible to reconstruct subsurface field from satellite altimeter data using the adjoint method,(2) it is possible to reconstruct shelf circulation from surface velocity data,(3) it is useful to include both altimeter data and drifter data to reconstruct large scale circulation,(4) it is possible to reconstruct the oceanic field beneath the surface mixed layr by assimilating surface data.The objectives initially listed in the proposal have been achieved. The information exchange was extremely useful for the PI and CI to develop their research at the initial stage. Less

1995-96由于数据同化是揭示海洋过程的一种新方法，因此首席调查员(PI)和联合调查员(CI)之间交换他们所拥有的信息是非常有用的。因此，我们于7月份在筑波召开了一次会议，会上其他研究人员也被邀请并共同工作，审查现有的方法和搜索数据集。PI访问了加拿大，研究了俄罗斯CI(生活在加拿大)开发的伴随方程方法。他们访问了日本一个半月，参加了国际和平机构的项目。他们参观了日本的许多研究所，并与日本科学家交流了知识。PI和俄罗斯CI向《海洋学杂志》提交了一篇论文。一名CI(Kamachi)访问了挪威，以调查卡尔曼滤波法。这次旅行非常有必要，因为日本没有这方面的专家。1996-97第一年的第一次会议之后，我们举行了第二次会议，m…邀请来自不同国家的五名CI，在Mutsu举行更多的国际会议。参加的总人数超过40人。与会者就比第一年更先进的数据同化方法交流了信息。建议包括：(1)在伴随方法中，物理简单的动力学模式可能更适合作为约束模式；(2)在卡尔曼滤波法中，当处理强非线性系统时，必须去除不稳定性。Pi访问了夏威夷大学，交换了关于北太平洋大气环流数据同化的信息。这些项目的成果是：(1)可以用伴随方法从卫星高度计数据重建次表层场，(2)可以从表层速度数据重建陆架环流，(3)同时包括高度计数据和漂流数据对重建大尺度环流是有用的；(4)通过同化表层数据重建表层混合层下的海区是可能的，已经达到了最初列出的目标。信息交流对PI和CI在初始阶段开展研究非常有用。较少

项目成果

D.A.Nechaev,M.I.Yaremchuk and M.Ikeda: "Vertical projection of surface velocity data using the variational assimilation method with quasigeostrophic dynamical constraints" Journal of Oceanography. (発行予定).

D.A.Nechaev、M.I.Yaremchuk 和 M.Ikeda：“使用具有准地转动力学约束的变分同化方法对表面速度数据进行垂直投影”《海洋学杂志》（待出版）。

D.A.Nechaev,M.I.Yaremchuk and M.Ikeda: "Vertical projection of surface velocity data using the variational assimilation method with quasigeostropphic dynamical constraints" Journal of Oceanography. (投稿中).

D.A.Nechaev、M.I.Yaremchuk 和 M.Ikeda：“使用具有准地转动力约束的变分同化方法对表面速度数据进行垂直投影”《海洋学杂志》（正在提交）。

D.A.Nechaev,M.I.Yaremchuk and M.Ikeda: "Vertical projection of surface velocity data using the variational assimilation method with quasi-geostrophic dynamical constraints" Journal of Oceanography. (発行予定).

D.A.Nechaev、M.I.Yaremchuk 和 M.Ikeda：“使用具有准地转动力学约束的变分同化方法对表面速度数据进行垂直投影”《海洋学杂志》（待出版）。

D.A.Nechaev, M.I.Yaremchuk and M.Ikeda: "Vertical projection of surface velocity data using the variational assimilation method with quasi-geostrophic dynamical constraints" Journal of Oceanography. (in press). (1997)

D.A.Nechaev、M.I.Yaremchuk 和 M.Ikeda：“使用具有准地转动力学约束的变分同化方法对表面速度数据进行垂直投影”海洋学杂志。