Next-Generation Air–Ocean–Wave Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS)

Introduction: A team of NRL scientists from the Marine Meteorology and Oceanography Divisions has successfully transformed the one-way air–ocean Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS®*) into a six-way fully coupled air–ocean– wave weather and marine forecasting system. This was accomplished using the state-of-the-art Earth System Modeling Framework (ESMF), making COAMPS the first limited area model to utilize ESMF in an effort to seamlessly couple multiple, individually skillful models into one flexible, coherent modeling system. The components used here consist of the COAMPS atmospheric model, the Navy Coastal Ocean Model (NCOM), two interchangeable wave models — Simulating WAves Nearshore (SWAN) and WAVEWATCH III — and a new air–sea coupler developed at NRL that surmounted many of the technical challenges that arose during the development of the coupled system. A mechanism was implemented in the air–sea coupler to support interoperable inter-exchange of two different wave models and different wave feedbacks to the ocean and atmosphere, a feature that enhances the capability of the coupled system to adapt new components. Additionally, special atmospheric, ocean, and wave hurricane observations were obtained to investigate and validate the sensitivity of hurricane intensity and track change in the forecast system due to various coupling processes.