NEMO (Nucleus for European Modelling of the Ocean) is an ocean modelling framework which is composed of "engines" nested in an "environment". The "engines" provide numerical solutions of ocean, sea-ice, tracers and biochemistry equations and their related physics. The "environment" consists in reference configurations, pre- and post-processing tools, interface to the other components of the Earth system, user interface, computer dependent functions and documentation of the system.

NEMO allows several ocean related components of the Earth system to work together or separately (i.e "standalone mode"). It also allows a two-way nesting via the AGRIF software. It is interfaced with the other components of the Earth system (atmosphere, land surfaces, ...) via the OASIS coupler.

NEMO releases

The latest stable release of NEMO is the version 4.0.2 (March 2020).

The NEMO ocean model has 3 major components:

• NEMO-OCE models the ocean {thermo}dynamics and solves the primitive equations
• NEMO-ICE (SI3: Sea-Ice Integrated Initiative) models sea-ice {thermo}dynamics, brine inclusions and subgrid-scale thickness variations
• NEMO-TOP (Tracers in the Ocean Paradigm) models the {on,off}line oceanic tracers transport and biogeochemical processes (using PISCES)

Additional capabilities: 

• Create embedded zooms seamlessly thanks to 2-way nesting package AGRIF
• Input-Output through effective XIOS software
• Coupling interface to other Earth system components based on OASIS
• Opportunity to integrate an external biogeochemistry model
• Versatile data interface
• Set of utilities is also provided to {pre,post}process your data

NEMO evolution

The NEMO Consortium pulling together 5 European institutes plans the sustainable development in order to keep a reliable evolving framework since 2008. It defines the multi-year development strategy that is implemented by the System Team on a yearly basis in order to regularly release a new version. When the need arises, working groups are created or resumed to gather the community expertise for advising on the development activities.

Target platforms

NEMO is intended to be a portable platform. It actually runs on a number of computers (target platforms).

Reference configurations

10 reference configurations are available for now, with their downloadable input files. These may evolve, depending on the area of interest of NEMO community and Consortium, following two main objectives: to allow the possibility to run a given configuration on a platform to be check that it works properly and to give a demonstrator to the user/project in order to build his own configuration.