Wind and Current Study at Detroit's Metropolitan Beach

Abstract

It was decided that pertinent studies to be carried out in the Beach area should be measurement of water current and wind. A current indicator was built early in t he summer. The unit built was a cylindrical structure about four feet in height with a diameter of one foot . The upper portion of the unit was filled with styrofoam for floatation. The lower end of the current indicator was connected by means of a short flexible tube to the lake bottom. The action of the water current on the indicator would be to tilt it much as it would a sea weed. Four mercury switches were so positioned in the unit that they would close a circuit as the unit tilted in one of four directions : north, east, south, or west. A closed circuit would activate a stylus on a recording unit in a shed on the beach. As the chart paper was moved past the marking pens (motion linear with time) each pen would record the result of one particular circuit closure. With four circuits entailed with current indication, four pens were used. The recording unit used had ten other pens which were made use of in recording wind direction (8 directions} and wind velocity. These pens employed the same principle for activation as the current stylii-closed circuits. The project was officially begun 14 August 1962 by inserting the current unit in eight feet of water about 500 feet off the Beach Shore. A cable connected to the electrical sensors of the current indicator carried the directional signal to the recorder in the shed. At the shed were also located an anemometer and wind vane to provide a wind direction and velocity record simultaneous with the current direction.