SURFEX (Surface Externalisée, in French) is a surface modelling platform developed by Météo-France in cooperation with the scientific community.
SURFEX is composed of various physical models for natural land surface, urbanized areas, lakes and oceans. It also simulates chemistry and aerosols surface processes and can be used for assimilation of surface and near surface variables.
SURFEX has its own initialisation procedures and can be used in stand alone mode and coupled to an atmospheric model.
In SURFEX, each model grid box is represented by four surface types : sea or ocean, water bodies (lakes, ...), urban areas and nature (soil and vegetation). Each surface type is modeled with a specific surface model and the total flux of the grid box results from the addition of the individual fluxes weighted by their respective fraction.
Summary of the main components of the surfex model
| Tile NATURE | The model for the tile "Nature" is the ISBA (interaction soil-biosphere-atmosphere) model |
| Tile TOWN | The model for the tile "Town" is the TEB (Town energy balance) model |
| Tile OCEAN | Surface fluxes above the tile "sea and ocean" can be treated in a very simple way or by using more physically based model |
| Tile WATER | Surface fluxes above the lake tile can be treated in a very simple way or by using the FLake model |
| Chemical scheme | Emission and deposition of dust and aerosols are treated over land and oceans |
| Data assimilation | Assimilation of near surface meteorological variables and remotely sensed variables can be performed using an optimal interpolation or an Ensemble Kalman filter scheme |

