The Finite Element Sea ice-Ocean Model (FESOM) and the Alfred Wegener Institute Climate Model (AWI-CM, based on ECHAM-FESOM), which were developed at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, are already applied on diverse time scales, from paleoclimate simulations to future projections. Unlike the traditional ocean models with structured square grids, FESOM uses triangle-based unstructured grids to simulate ocean currents, hydrography and sea ice. With the flexibility and malleability of triangle meshes, FESOM can simulate the global ocean circulation with variable mesh resolution and resolve key regions, coastlines or narrow straits without involving additional nesting techniques.
The performance of FESOM and AWI-CM in polar region shows that high resolution simulation can significantly reduce the model biases and better reproduce the realistic ocean and sea ice states. The applications of, FESOM to discuss the mechanism of sea ice inter-annual variability in the Barents Sea, and AWI-CM to study the climate response to West Antarctic Ice Sheet (WAIS) collapse during Last Interglacial will also be shown in this talk.