High-Resolution Modeling of Extreme Ocean Wave Climatology in Coastal Waters of the Western North Atlantic Ocean

Abstract:

This study generates a high-resolution, validated hindcast of ocean waves to investigate the climatology of extreme waves in coastal waters of Western North Atlantic Ocean. We consider coastal waters as the region between the shoreline and a water depth of 300 m offshore. We utilize a coupled circulation-wave model, ADCIRC-SWAN, to simulate wind waves and swells for a 40-year historical time period between 1980 and 2020. The computational mesh covers the entire Atlantic Ocean and has a spatial resolution of between 1km and 5km in the U.S. coastal waters and gradually coarsens to 50km in the deep ocean. The bathymetry in the mesh is based on the GEBCO_2020 grid that has a resolution of 15 arc second (about 500m). The circulation-wave model accounts for the effects of wave-current interactions on the wave characteristics by including tides and storm surges in the simulations. The meteorological forcing dataset is based on 3hourly pressure and wind fields from ERA5 reanalysis dataset that has a resolution of 30 km. Simulated wave characteristics are compared with buoy measurements to quantify the model uncertainties. The validated model outputs are statistically analyzed to determine the climatology of extreme waves in coastal waters of the Western North Atlantic Ocean.