Numerical Model of St. Lawrence River Estuary

The numerical scheme of tidal propagation involved an explicit finite-difference solution to the shallow-water wave equations. This model was combined with one-dimensional models of the higher reaches of the St. Lawrence and Saguenay Rivers. The resulting model represents a complete simulation of the estuary to the limits of the tidal influence. Computed values of the depth-averaged velocities showed good agreement with field recordings of surface velocities in the upstream section of the lower estuary. However, results in the downstream section indicated the magnitude of the computed velocities to be lower than the recorded surface velocities. This inconsistency has been related to the degree of the vertical density stratification existing in the estuary. An examination was made of the influence of the Coriolis force on the flow in the lower estuary.