What is the tidal period between low and high tide on the Great Lakes?
There doesn’t seem to be much data on tides in the Great Lakes. You are right that the Moon does affect the Great Lakes, but the tides are almost imperceptible. Data of water levels in each of the Great Lakes vary greatly due to meteorological conditions and natural basin oscillation, both of which override tidal forces. Sometimes, winds can set up seiches in the Great Lakes, causing water levels to rise and fall significantly and in a periodic fashion (like tides). The period of these oscillations is given by a standing wave equation for an enclosed basin. T = 2L/n*sqrt(gd) L= basin length, n = harmonic order, g = gravitational acceleration (9.81 m/s^2), and d = average depth of basin sqrt(gd) is the speed of waves in shallow water. Since all seiches have wavelengths much greater than 20 times the average depth (definition of shallow water), sqrt(gd) is the equation.
