Data assimilation for marine monitoring and prediction:: The MERCATOR operational assimilation systems and the MERSEA developments
Data assimilation for marine monitoring and prediction:: The MERCATOR operational assimilation systems and the MERSEA developments
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DOI：
10.1256/qj.05.142
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发表时间：
2005-10-01
影响因子：
8.9
通讯作者：
Verron, J.
中科院分区：
文献类型：
--
作者：
Brasseur, P.;Bahurel, P.;Verron, J.
在过去15年中，在国家一级采取了一些举措，发展在区域和/或全球范围运作的海洋预报系统。这些努力之间的协调是通过全球海洋数据同化实验在国际上组织的。法国的MERCATOR项目是全球空间碎片协进会的主要参与者之一。MERCATOR系统定期同化各种观测数据，如多卫星高度计数据、海面温度和现场温度和盐度剖面，重点是海洋动力学的高分辨率尺度MERCATOR系统的同化战略是以一系列日益复杂的方法为基础的，包括最佳插值、卡尔曼滤波和变分方法，这是逐步部署通过系统d '同化MERCATOR（SAM）系列。SAW是基于一个降阶的最佳插值，可以使用“高度测量”或“多数据”设置操作;它依赖于可分离性的概念，假设相关性可以分离成水平和垂直贡献的乘积。第二个版本SAM-2正在开发中，将包括奇异进化扩展卡尔曼滤波器的新功能，如三维、多变量误差模式和自适应方案。第三个是SAM-3，考虑变分方法，如增量四维变分算法。在GODAE期间评估的大多数业务预报系统是基于最小二乘统计估计假设高斯误差。在欧盟MERSEA（欧洲地区海洋环境和安全）项目的框架内，正在进行研究，以准备下一代业务海洋监测和预报系统。研究工作将探索非线性同化公式，以克服当前系统的局限性。本文提供了一个概述的发展进行MERSEA与SEEK滤波器，Enhancement卡尔曼滤波器和顺序重要性重采样滤波器。
During the past 15 years, a number of initiatives have been undertaken at national level to develop ocean forecasting systems operating at regional and/or global scales. The co-ordination between these efforts has been organized internationally through the Global Ocean Data Assimilation Experiment (GODAE). The French MERCATOR project is one of the leading participants in GODAE. The MERCATOR systems routinely assimilate a variety of observations such as multi-satellite altimeter data, sea-surface temperature and in situ temperature and salinity profiles, focusing on high-resolution scales of the ocean dynamics.The assimilation strategy in MERCATOR is based on a hierarchy of methods of increasing sophistication including optimal interpolation, Kalman filtering and variational methods, which are progressively deployed through the Systeme d'Assimilation MERCATOR (SAM) series. SAW is based on a reduced-order optimal interpolation which can be operated using 'altimetry-only' or 'multi-data' set-ups; it relies on the concept of separability, assuming that the correlations can be separated into a product of horizontal and vertical contributions. The second release, SAM-2, is being developed to include new features from the singular evolutive extended Kalman (SEEK) filter, such as three-dimensional, multivariate error modes and adaptivity schemes. The third one, SAM-3, considers variational methods such as the incremental four-dimensional variational algorithm.Most operational forecasting systems evaluated during GODAE are based on least-squares statistical estimation assuming Gaussian errors. In the framework of the EU MERSEA (Marine EnviRonment and Security for the European Area) project, research is being conducted to prepare the next-generation operational ocean monitoring and forecasting systems. The research effort will explore nonlinear assimilation formulations to overcome limitations of the current systems. This paper provides an overview of the developments conducted in MERSEA with the SEEK filter, the Ensemble Kalman filter and the sequential importance re-sampling filter.