[A-CG47] Status and future view on global ocean observation: toward achievement and development for OneArgo

[ACG47-02] An overview of SynObs Flagship OSE and its preliminary results

★Invited Papers

*Shoichiro Kido¹, Yosuke Fujii², Yasumasa Miyazawa¹, Ichiro Ishikawa² (1.Application Laboratory, Japan Agency for Marine-Earth Science and Technology, 2.Meteorological Research Institute, Japan Meteorological Agency)

Keywords:Ocean observation, Data assimilation, Observation system experiment

The Synergistic Observing Network for Ocean Prediction (SynObs) project, which is endorsed as the United Nations Decade of Ocean Science for Sustainable Development project, is aimed to extract maximum benefits from the combination among various ocean observation platform measurements for ocean prediction. In the SynObs project, a series of Observing System Experiments (OSEs) and Observing System Simulation Experiments (OSSEs) will be conducted under coordinated protocols to robustly evaluate the impact of individual types of ocean observations. Currently, more than 10 ocean prediction systems (including 2 systems from Japan) with various model resolutions and data assimilation methods are participating in this activity, and results of multi-system OSEs/OSSEs will be compiled into a database as an example of ocean digital twin so that a broad oceanographic community can analyze the impact of the observations. In this presentation, we will introduce experimental designs of the SynObs Flagship OSEs and their preliminary results based on our ocean nowcasting/forecasting system.

In the SynObs Flagship OSEs, a series of data assimilation experiments that partially exclude observational information assimilated into the system, and comparisons of these results with the reference experiment allow us to isolate the impact of various ocean observations such as that of Argo profiling floats, satellite observations of sea level and sea surface temperature, and in-situ observations. Preliminary analysis of OSEs with our semi-global ocean monitoring/forecasting systems with different horizontal resolutions (0.1°x0.1° versus 0.5°x0.5°) demonstrated that the assimilation of both Argo profiling floats and satellite observations is crucial for an accurate representation of hydrographic structure in the world oceans, and the system with finer horizontal resolution is better extract benefits from observations compared to the low-resolution version. We will also discuss results from other systems depending on their status/availability.