Periodic Reporting for period 3 - IMMERSE (Improving Models for Marine EnviRonment SErvices)
Período documentado: 2021-06-01 hasta 2023-02-28
The Copernicus Marine Monitoring Environment Service (CMEMS) routinely provides data products on the state of the oceans. These data products describe the present state of the ocean, its evolution over the last decades and predictions of the situation a few days ahead.
Marine monitoring services rely on both observational data and numerical ocean models. Observational data are collected by in-situ sensors and observation satellites as for instance the Copernicus Sentinel series. Numerical models are then used to extrapolate available information at locations and at times where no observational data is available.
Upcoming satellite and in-situ observations will cover a wider range of oceanic properties and will be available with an improved accuracy at finer resolution, which should open many new applications at decision-relevant scales. A key challenge is therefore to prepare the integration of this variety of new data sources in numerical ocean models.
The IMMERSE project has focused on preparing numerical ocean models to this challenge of providing consistent marine data products at kilometric resolutions for the next generation Copernicus marine services. The project has improved the accuracy, the efficiency and the robustness of the NEMO numerical ocean model, which is widely used in the current generation of marine monitoring services.
This has been achieved by using the most recent mathematical concepts and high performance computing technologies for solving the equations governing ocean dynamics on a much finer discrete grid. The IMMERSE project also prepared NEMO to finer spatial and temporal resolutions by improving the physical representation of the oceanic motions happening at kilometric scale, which include intense fronts, surface waves, tidal currents and strong interactions with the underlying bathymetry.
IMMERSE project also prepared the integration of this improved model codebase in Copernicus marine services, by studying how to optimally combine the new high resolution observations with numerical ocean models. The project put much effort into demonstrating how its new developments will impact Copernicus marine services, its products and its downstream applications.
Marine monitoring services rely on both observational data and numerical ocean models. Observational data are collected by in-situ sensors and observation satellites as for instance the Copernicus Sentinel series. Numerical models are then used to extrapolate available information at locations and at times where no observational data is available.
Upcoming satellite and in-situ observations will cover a wider range of oceanic properties and will be available with an improved accuracy at finer resolution, which should open many new applications at decision-relevant scales. A key challenge is therefore to prepare the integration of this variety of new data sources in numerical ocean models.
The IMMERSE project has focused on preparing numerical ocean models to this challenge of providing consistent marine data products at kilometric resolutions for the next generation Copernicus marine services. The project has improved the accuracy, the efficiency and the robustness of the NEMO numerical ocean model, which is widely used in the current generation of marine monitoring services.
This has been achieved by using the most recent mathematical concepts and high performance computing technologies for solving the equations governing ocean dynamics on a much finer discrete grid. The IMMERSE project also prepared NEMO to finer spatial and temporal resolutions by improving the physical representation of the oceanic motions happening at kilometric scale, which include intense fronts, surface waves, tidal currents and strong interactions with the underlying bathymetry.
IMMERSE project also prepared the integration of this improved model codebase in Copernicus marine services, by studying how to optimally combine the new high resolution observations with numerical ocean models. The project put much effort into demonstrating how its new developments will impact Copernicus marine services, its products and its downstream applications.
The project activities have focused on improving the NEMO codebase so that its computational performances are adapted to exploit future HPC technologies in the context of CMEMS systems. The combination of HPC and Kernel improvements have yielded a 2x acceleration of the code in realistic applications.
The project has also contributed to improving the representation of ocean dynamics and biogeochemistry at kilometric scale with improved accuracy. A series of targeted developments have been carried out for improving key aspects of ocean dynamics at kilometric scale including air-sea interactions, wave-current interactions and sea ice rheology. The impact of these developments have been carefully assessed against observations.
Demonstrators for the exploitation of future high resolution observing systems have been implemented. They consist of prototype systems for global forecasting, regional forecasting and global reanalysis. The demonstrators include a model describing the global ocean at 1/36° resolution (2-3km). These demonstrators are available openly on the project GitHub organization and their performance have been described in detail in a series of project deliverables.
Project activities have also focused on preparing the articulation of downstream systems with the next generation of CMEMS global and regional forecasting systems. This includes tools for generating boundary conditions for downstream systems and pilot studies measuring the benefit of improved CMEMS products for downstream applications.
The results of the IMMERSE developments have been delivered in open source, well-documented, software codes and prototypes systems. Developments to the NEMO ocean model have been delivered through an improved gitlab server including a continuous testing service. IMMERSE developments to NEMO have been included in NEMO v4.2.0 v4.2.1 and v4.2.2 and have prepared the release of NEMO v5.0 in 2025.
The project has also contributed to improving the representation of ocean dynamics and biogeochemistry at kilometric scale with improved accuracy. A series of targeted developments have been carried out for improving key aspects of ocean dynamics at kilometric scale including air-sea interactions, wave-current interactions and sea ice rheology. The impact of these developments have been carefully assessed against observations.
Demonstrators for the exploitation of future high resolution observing systems have been implemented. They consist of prototype systems for global forecasting, regional forecasting and global reanalysis. The demonstrators include a model describing the global ocean at 1/36° resolution (2-3km). These demonstrators are available openly on the project GitHub organization and their performance have been described in detail in a series of project deliverables.
Project activities have also focused on preparing the articulation of downstream systems with the next generation of CMEMS global and regional forecasting systems. This includes tools for generating boundary conditions for downstream systems and pilot studies measuring the benefit of improved CMEMS products for downstream applications.
The results of the IMMERSE developments have been delivered in open source, well-documented, software codes and prototypes systems. Developments to the NEMO ocean model have been delivered through an improved gitlab server including a continuous testing service. IMMERSE developments to NEMO have been included in NEMO v4.2.0 v4.2.1 and v4.2.2 and have prepared the release of NEMO v5.0 in 2025.
The progress reached through the project activities are beyond the state-of-the-art in their respective fields and will have societal implications through their integration in europezn marine monitoring services and downstream systems.
The developments to the NEMO ocean model are based on innovative mathematical concepts for discretizing the equations of fluid motions, new insight on the physics of ocean fine scale processes and innovative approaches for leveraging complex computer architectures. They have substantially improved the accuracy, the computational efficiency and the robustness of NEMO, which is one of the core building blocks of European marine monitoring services.
The activities on the integration of model and observational data, as for instance the study of predictability and the quantification of forecast accuracy, are also beyond the state of the art in terms of targeted resolution. The demonstrators and prototype systems deployed during the project, as for instance the global 1/36° model, are also beyond state-of-the-art amongst existing operational systems.
Overall, the progress beyond state of the art reached during the project provides a robust foundation for the evolution of marine monitoring services and downstream systems. They will allow for an optimal exploitation of new observing capabilities from both in-situ and satellite platforms.
The developments to the NEMO ocean model are based on innovative mathematical concepts for discretizing the equations of fluid motions, new insight on the physics of ocean fine scale processes and innovative approaches for leveraging complex computer architectures. They have substantially improved the accuracy, the computational efficiency and the robustness of NEMO, which is one of the core building blocks of European marine monitoring services.
The activities on the integration of model and observational data, as for instance the study of predictability and the quantification of forecast accuracy, are also beyond the state of the art in terms of targeted resolution. The demonstrators and prototype systems deployed during the project, as for instance the global 1/36° model, are also beyond state-of-the-art amongst existing operational systems.
Overall, the progress beyond state of the art reached during the project provides a robust foundation for the evolution of marine monitoring services and downstream systems. They will allow for an optimal exploitation of new observing capabilities from both in-situ and satellite platforms.