Transport in Lake Water Quality Modeling

Abstract

The relationship between model formulation and dispersive transport is examined for lake water quality models. Two basic model types are identified: (1) The finite difference model (a continuum approach); and (2) the multiple‐box model (a discrete approach). Analysis of these two approaches indicates that the multiple‐box model formulation introduces substantial implicit dispersion as a consequence of its discrete structure. Due to this implicit dispersion, multiple‐box model exchange flow or dispersion parameters cannot be determined directly based on the hydrodynamics of the prototype lake—only calibration is a viable approach. A systematic procedure to construct and calibrate multiple‐box models that accounts for the model's implicit dispersion is presented.