FESOM (Finite-Element/volumE Sea ice-Ocean Model) is a multi-resolution sea ice-ocean model that solves the equations of motion on unstructured meshes. The model is developed and supported by researchers at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), in Bremerhaven, Germany.


FESOM implements the idea of using unstructured meshes with variable resolution. This mesh flexibility allows to increase resolution in dynamically active regions, while keep a relatively coarse-resolution setup elsewhere. FESOM allows global multi-resolution simulations without traditional nesting.

The dynamical core of the original version of FESOM employs the finite element method; its successor, FESOM2, uses the finite volume method, which increases the computational efficiency by a factor of 3-5. Both versions include the Finite-Element Sea Ice Model (FESIM).

Excellent scalability characteristics allow to make effective use of massively parallel supercomputers. 

FESOM is also used in the AWI Climate Model (AWI-CM), which contributes to CMIP6.


Paper on FESOM2 scalability and optimisation

The new paper "Scalability and some optimization of the Finite-volumE Sea ice–Ocean Model, Version 2.0 (FESOM2)" was recently published in GMD. The authors show that "... in terms of throughput, FESOM2 is on a par with state-of-the-art structured ocean models and, in a realistic eddy-resolving configuration (1/10° resolution), can achieve about 16 years per day on 14 000 cores. This suggests that unstructured-mesh models are becoming very competitive tools in high-resolution climate modeling."

First CMIP6 data from AWI-CM on ESGF

First data for CMIP6 project generated by AWI-CM start to appear on ESGF nodes. For now DECK and scenarioMIP are available. 

Fast EVP Solutions in a High‐Resolution Sea Ice Model

FESOM2 high resolution setup was used to demonstrate that EVP sea ice dynamics can be made faster without degrading the quality of the solution.