A numerical study of the Niagara River discharge near-shore flow field in Lake Ontario

A two dimensional explicit finite element hydrodynamic model was developed to study near shore flow circulation near the month of the Niagara River di scharge into Lake Ontario and to investigate the influence of grid spatial resolution on the model results. An extensive set of numerical experiments was carried our, using more than 40 different numerical grid meshes. Lagran gian tracer paths were calculated to illustrate the flow trajectories under different hydrodynamic forcing conditions and goon comparison with field d ata reported in the literature is shown. Spatial step sizes of slightly les s than 100 m were found to be sufficient for modeling near-shore flow struc ture, while much larger steps (several km) were used farther off-shore. Thi s model allows a better understanding of the effects of various forcing con ditions (primarily wind) on the flow and mixing characteristics of the Niag ara River discharge and formation of the coastal boundary current along the southern shoreline of Lake Ontario.