Abstract
Measurement of the electric potential produced across a tidal stream is an inexpensive and relatively maintenance free means of monitoring volume flow. Comparison of the electric signal to transports determined from current meter records is used to calibrate the system. A volume flow of 100 m3 per sec will induce a potential near 1 mV. Salinity and temperature changes at the electrodes will induce potentials of 500 μV per ‰ and 350 μV per °C. Transport estimates may need to be corrected for such effects. Examples of measurements made at two locations, Great Bay, New Hampshire, and Lake Pontchartrain, Louisiana, illustrate that the method is capable of yielding volume flow measurements with an uncertainty of about 15%.
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Swenson, E.M. Electromagnetic measurements of tidal transports in estuaries. Estuaries 4, 161–166 (1981). https://doi.org/10.2307/1351471
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DOI: https://doi.org/10.2307/1351471