Impact of Sea‐Ice Model Complexity on the Performance of an Unstructured‐Mesh Sea‐Ice/Ocean Model under Different Atmospheric Forcings

We have equipped the unstructured-mesh global sea-ice and ocean model FESOM2 with a set of physical parameterizations derived from single-column Icepack. The update has substantially broadened range processes that can be represented by model. new features are directly implemented on unstructured mesh, thereby benefit flexibility comes it in terms spatial resolution. A subset parameter space three configurations, increasing complexity, been calibrated an iterative Green's function optimization method to test impact representation. Furthermore, explore sensitivity results different atmospheric forcings, each configuration was separately for NCEP-CFSR/CFSv2 ERA5 forcings. suggest complex formulation leads better agreement between modeled observed concentration snow thickness, while differences smaller thickness drift speed. However, choice forcing also impacts simulations observations, being particularly beneficial simulated In this respect, our indicate calibration compensate among forcings simpler (i.e., no heat capacity) than more realistic formulations prognostic distribution sea ice enthalpy.