New York Bight Study. Report 1, Hydrodynamic modeling

Abstract : As a part of the New York (NY) Bight Feasibility Study, a three- dimensional hydrodynamic model of the NY Bight was developed and applied by the Coastal Engineering R h Center of the U.S. Army Engineer Waterways Experiment Station. The study used the three-dimensional hydrodynamic model CH3D-WES for this purpose. A 76 x 45 cell boundary-fitted curvilinear grid was employed in the horizontal and five to ten sigma layers were used in the vertical. Steady- state and diagnostic tests were initially performed, using M, and mixed tides, cross-shelf gradients, winds, and freshwater flows in the Hudson River. All of the tests were successful in reproducing known circulation patterns of the NY bight system. The model was next successfully calibrated and verified against prototype tidal elevations and currents measured during April and May 1976. As a demonstration of the feasibility of long-term modeling, the hydrodynamics, including salinity and temperature, were simulated for the period April-October 1976. Model results compared favorably with available prototype temperature measurements. Model output was furnished to a water quality model of the NY bight, which successfully reproduced the hypoxic event of 1976. Model results also were used successfully to run particle tracking and oil spill models of the NY Bight. Finally, the model was demonstrated for the Long Island Sound and East River areas, for the period of May-July 1990. Computed results for elevation, velocity, salinity, and temperature in the Sound as well as net flux in the East River matched measurements reasonably. Feasibility study, Models, Three- dimensional, Hydrodynamics, Monitoring, Water quality, Long Island Sound, New York Bight