Contributing to developping NEMO ocean model

The MEOM team has a longstanding experience in developping and using numerical softwares and geoscientific models alongside research in oceanography. Over the past 15 years, we have been contributing actively to the development of NEMO, which is today, the main geoscientific model used in our group. We indeed believe that numerical software is key to advancing research in oceanography. This is why we devote continuous efforts to supporting NEMO.

The Nucleus for European Modelling of the Ocean NEMO is an ocean modeling framework, distributed under CeCILL license, and used by a large community (with about ~100 registered projects and ~1000 registered users in 2015) for oceanographic research, operational oceanography, seasonal forecast and climate projections. Since 2008, its development is shared within a european consortium including CNRS (France), Mercator-Ocean (France), NERC (UK), Met Office (UK), CMCC (Italy) and INGV(Italy).

NEMO combines several modelling components, adapted to a wide range of applications. NEMO includes an ocean physics component (NEMO-OPA), an interactive sea-ice component (NEMO-LIM), and interactive Lagrangian iceberg component (NEMO-ICB), a transport component for ocean biogeochemistry (NEMO-TOP), a data-assimilation component (NEMO-TAM), a virtual observation generator (NEMO-OBS) and an adaptative mesh-refinement component (AGRIF).

Our group contributes to NEMO is several ways. As users of NEMO, we carry out frontier simulations that push the limits of NEMO capabilities. Our research projects often require NEMO model configurations to run on thousands of cores. Recent ensemble simulations at eddying resolution and basin-scale, submesoscale permitting simulations now push this limit beyond 10 000 cores. Our activity therefore helps calibrating and optimizing NEMO for massively parallel applications.

Since 2003, our group has been leading the DRAKKAR coordination, and therefore contributed to organizing the community of NEMO users. DRAKKAR indeed serves as a forum for sharing NEMO global model configuration. DRAKKAR members share forcing sets, tools and expertise for various frontiers simulations with NEMO. Every January, the MEOM group organizes and hosts the DRAKKAR annual workshop in Grenoble.

We also have a more formal contribution to NEMO activities with some MEOM group members being officially involved in NEMO system team and NEMO developpers’ commitee. We are in particular leading NEMO working group on data assimilation component (NEMO-ASSIM). Alongside our colleagues in France, UK and Italy, we also contribute actively to setting NEMO’s strategy for future developments so that NEMO continues serving the need of ocean science, climate and operational applications.