Predicting Nearshore Hydrodynamics Using the Coupled Ocean Atmosphere Prediction System (COAMPS)

The Coupled Ocean Atmospheric Mesoscale Prediction System (COAMPS) is a modeling suite of atmospheric, ocean circulation, and wave models that share information using the Earth System Modeling Framework (ESMF). Typically, COAMPS is applied at horizontal scales of hundreds of meters or more. In this application, we evaluate the COAMPS for horizontal scales of 10 meters in the cross shore direction and 15 meters in the along shore direction. We use the Navy Coastal Ocean Model (NCOM) for ocean circulation and Simulating Waves Nearshore (SWAN) for wave predictions. The area of the Field Research Facility at Duck, North Carolina is modeled using in situ measurements for bottom and wave boundary conditions. We model only wave-driven circulation and include a parameterized form of wave roller effects. Model results over the barred bathymetry show skill when compared to measurements of significant wave height and the along shore and across shore velocity components. When the wave roller parameterization is utilized, we observe a shoreward shift in the peak of the alongshore velocity. However, the wave roller parameterization introduces an unrealistic discontinuity shoreward of the bar trough. Furthermore, we find COAMPS, when applied at nearshore scales, to be less efficient computationally than other coupled modeling systems.