FESOM-C is a recently designed coastal branch of the global Finite Element (Volume) Sea-ice Ocean Model (FESOM). It was developed to focus on smaller scales than FESOM and on physical and dynamical processes that are commonly not accounted for in large-scale models. FESOM-C solves 3D primitive equations under the Boussinesq, hydrostatic, and traditional approximations for momentum, continuity, and density constituents. The model has already been validated through a series of idealized and realistic setups. FESOM-C employs a cell-vertex finite volume discretization and works with any configuration of triangular, quadrangular, or hybrid meshes, ensuring both geometrical flexibility and numerical efficiency in coastal simulations. Additionally, FESOM-C includes Lagrangian backward/forward tracking and sediment modules. The overarching goals of FESOM-C are sustainable coastal management and the accurate modeling of coastal dynamics within the Earth System Model (ESM) context.
 

FESOM-C current stage

• Cell-vertex finite volume discretization
• Any configurations of triangular, quadrangular or hybrid meshes
• Terrain following vertical coordinate
• High order horizontal advection schemes with limiters
• Implicit 3d-order vertical advection schemes, implicit vertical viscosity 
• Biharmonic horizontal viscosity, Smagorinsky viscosity
• GOTM turbulence library for the vertical mixing
• Rivers through solid boundary in streaming form/ Rivers as open boundary conditions
• Tidal potential /Open boundary prescription of amplitudes and phases
• Wetting/drying (several options)
• Particle tracking Lagrangian module
• Sediment module
• Neural network module dedicated to the recover of surface currents from depth-averaged solution
• Ice module
 

Animation. Demonstration of wetting/drying option.

Fig. Clouds of the tracers, resulting from backtracking for 3 weeks  superimposed on a bathymetry map [m]. Dashed lines illustrate depth-averaged solutions, while solid lines illustrate solutions for the surface. Green lines represent the borders of MPAs. Magenta dots indicate the positions of measurements where larvae were identified and the tracers were realized. Turquoise dots show the positions of tracers 3 weeks before sampling.

Animation. Transport of massless tracers in the Sylt-Rømø Bight superimposed on depth-averaged velocity field. Braun color indicates dry zones. Authors: V. Sidorenko, A. Androsov, K. H. Wiltshire

Fig. Change in the tidal zone, various sea level rise scenarios. Authors: G.Konyssova, V. Sidorneko, A. Androsov, S. Rubinetti, L.Sander, K.H.Wiltshire

Animation. Modeled Acqua alta events in the Venice lagoon. Authors: S. Rubinetti, I. Kuznetsov, V. Sidorenko, A. Androsov, M. Gnesotto, A. Rubino, D. Zanchettin

• Potter Cove. SPM study

Animation. Simulated SPM Dynamics in Potter Cove. Authors: C. Neder, V. Sidorenko, A. Androsov, I. Kuznetsov, D. Abele, U. Falk, I. R Schloss, R. Sahade, K. Jerosch

Fig. Sketch of the designed plume spreading test case, representing an estuary-shelf system where dynamics combine nonlinear flow regimes with sharp frontal boundaries and linear regimes with cross-shore geostrophic balance.

Animation. Left panel: high order hybrid advection scheme; Right panel: 2d order upwind. Authors: V. Sidorenko, T. T. Sidorenko, T. Kärnä, A. Androsov, K. Androsov, K. K. Klingbeil, S. Danilov, H. Burchard