ICONGETM v1.0 – Flexible two-way coupling via exchange gridsbetween the unstructured-grid atmospheric model ICON and thestructured-grid coastal ocean model GETM

Abstract. Coupled atmosphere-ocean models are developed for process understanding at the air-sea interface. Over the last 20 years, there have been studies involving simulations in the range of sub-annual simulations to climate scenarios. The development of coupled models highly depends on the kind and quality of the required data exchange between the model interfaces. This work achieved the development of a two-way coupled atmosphere-ocean model ICONGETM with flexible data exchange via exchange grids provided by the widely used ESMF regridding package. The regridding of flux data between the unstructured atmosphere model ICON and the structured regional ocean model GETM is conducted via these exchange grids. The newly developed model ICONGETM has been demonstrated for a coastal upwelling scenario in the Central Baltic Sea.