Expected impact of the future SMOS and Aquarius Ocean surface salinity missions in the Mercator Ocean operational systems: New perspectives to monitor ocean circulation

REMOTE SENSING OF ENVIRONMENT

卷:112

Article

Tranchant, Benoit^1,2  Testut, Charles-Emmanuel¹  Renault, Lionel³  Ferry, Nicolas¹  Birol, Florence³  Brasseur, Pierre⁴ 

[1] Mercator Ocean, F-31520 Ramonville St Agne, France

[2] CERFACS, F-31057 Toulouse 01, France

[3] LEGOS, F-31400 Toulouse, France

[4] LEGI, F-38041 Grenoble 9, France

关键词: data assimilation;    Sea Surface Salinity;    OSSE;   

DOI  :  10.1016/j.rse.2007.06.023

来源: Elsevier

【 摘 要 】

Sea Surface Salinity (SSS) has never been observed from space. The SSS from planned satellite missions such as Soil Moisture and Ocean Salinity (SMOS) and Aquarius is a key to better understanding how ocean circulation is related to water cycle and how both these systems are changing through time. The Observing System Simulation Experiments (OSSEs) presented in this paper has been carried out with an ocean forecasting system developed within the French oceanographic Mercator Ocean context. They consist in hindcast experiments assimilating an operational dataset (Sea Surface Temperature (SST), in-situ profiles of temperature and salinity and Sea Level Anomalies (SLA)) and various simulated SMOS and Aquarius Sea Surface Salinity (SSS) data. These experiments use an eddy permitting model (1/3 degrees) covering the North Atlantic from 20 degrees S to 70 degrees N. The new generation of fully multivariate assimilation system referred to as SAM2v1 which is being developed from the SEEK (Singular Evolutive Extended Kalman) algorithm is used. This scheme is a Reduced Order Kalman Filter using a 3D multivariate modal decomposition of the forecast error covariance. The OSSEs enabled us to show the positive impact of SSS assimilation on the Mercator Ocean operational forecasting system. These experiments particularly show the importance to specify appropriated observation errors and the impact of having and/or combining different observing system. Several conclusions can be highlighted such as the importance of the space/time scales consistency between the data products and our ocean prediction systems. This study has to be considered as an important step for assimilation of SSS measured from space. Further studies have to be conducted with other simulated data, other oceanic configurations and other improved assimilation schemes. (C) 2007 Elsevier Inc. All rights reserved.

【 授权许可】

Free