A Numerical Model for Wind-Driven Circulation in Lakes Michigan and Huron

Abstract A numerical model of time-dependent wind-driven currents in Lakes Michigan and Huron is investigated. The dynamical model is for a homogeneous lake involving only vertical turbulent mixing. After reduction from 3 to 2 space dimensions the equations are mapped onto a plane in which the irregular basin is transformed into a series of connected rectangles; the equations are then written in finite-difference form for an equally spaced grid mesh on the new plane. Two numerical integrations are made. Comparison of the rate of generation of longshore transport between the model and observations is made; also comparison of the free modes of the model with observed and calculated oscillations of water level are made. The results indicate a feasible model for numerical integration over an irregular region involving a wide range of scales of motion.