Water Science and Engineering · 2016 · 75 citations · 24 references
Natural SciencesOcean EngineeringOceanographyOcean ModelingOcean WavesPhysical OceanographyCoastal HydrodynamicsNearshore HydrodynamicsTidal CurrentsTidal DynamicsWave EnergyWave Energy DissipationBottom Friction EffectsCoastal Wave DynamicsHydrodynamic AnalysisHydrodynamic Response AnalysisNearshore Wave ModelingStorm Surge ModelingTidal Residual CurrentsWave Dissipation
The Gulf of Maine’s southern coast is vulnerable to nor’easter‑induced flooding, with Georges Bank dissipating wave energy through bottom friction and coastal longshore currents driven by wind and radiation stress that diminish with depth. The study employed a fully coupled SWAN‑ADCIRC model to simulate the 2007 Patriot's Day storm, analyzing wave and circulation fields, wave‑energy dissipation that reduces significant wave height and alters currents, and the resulting residual currents over Georges Bank and the coast. The model accurately reproduced observed tide‑surges and waves, revealing residual currents up to 0.3 m/s over Georges Bank, a 0.8 m storm surge along the western Gulf of Maine, and a 0.2 m wave set‑.
The southern coast of the Gulf of Maine in the United States is prone to flooding caused by nor'easters. A state-of-the-art fully-coupled model, the Simulating WAves Nearshore (SWAN) model with unstructured grids and the ADvanced CIRCulation (ADCIRC) model, was used to study the hydrodynamic response in the Gulf of Maine during the Patriot's Day storm of 2007, a notable example of nor'easters in this area. The model predictions agree well with the observed tide-surges and waves during this storm event. Waves and circulation in the Gulf of Maine were analyzed. The Georges Bank plays an important role in dissipating wave energy through the bottom friction when waves propagate over the bank from offshore to the inner gulf due to its shallow bathymetry. Wave energy dissipation results in decreasing significant wave height (SWH) in the cross-bank direction and wave radiation stress gradient, which in turn induces changes in currents. While the tidal currents are dominant over the Georges Bank and in the Bay of Fundy, the residual currents generated by the meteorological forcing and waves are significant over the Georges Bank and in the coastal area and can reach 0.3 m/s and 0.2 m/s, respectively. In the vicinity of the coast, the longshore current generated by the surface wind stress and wave radiation stress acting parallel to the coastline is inversely proportional to the water depth and will eventually be limited by the bottom friction. The storm surge level reaches 0.8 m along the western periphery of the Gulf of Maine while the wave set-up due to radiation stress variation reaches 0.2 m. Therefore, it is significant to coastal flooding.
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