This dataset comprises three NetCDF files, one for each of three models of global ocean transport: a 1º global configuration of the Nucleus for European Modelling of the Ocean (NEMO), a recent 2º solution of the Ocean Circulation Inverse Model (OCIM), and a 2º solution of the Total Matrix Intercomparison (TMI).

Each file provides the steady-state three-dimensional distributions of six dye tracers and the ideal age tracer.

The dye tracers represent water-mass fractions, or the fraction of local water volume that was last at the surface in a specific source region. The six source regions are: Antarctic marginal seas (AA), high southern latitudes (HS), mid southern latitudes (MS), low latitudes (LL), northern North Pacific (NP) and northern North Atlantic and Arctic (NA). They are illustrated here on the right and can be deduced from surface distributions of the dye tracers in each file.

The ideal age tracer represents the mean time elapsed since the last surface contact of local seawater.

More detailed documentation of the models and tracers can be found in the following publication:

Millet, B., de Lavergne, C., Gray, W.R., Ethé, C., Madec, G., Holzer, M., DeVries, T., Gebbie, G., Roche, D. Global ocean ventilation: a comparison between a general circulation model and data-constrained inverse models. ESS open archive (2024).