抄録
The real-time observation system of water levels is required to establish along coastal areas. The on-air acoustic tide gauge is newly developed here. It does not require the installation of the well in the water, so the construction cost is expected to be lower than conventional types. However, the accuracy is not verified in detail at the sea area which has large amplitudes of tides. In this study, tide data is continuously observed at the observation point in the Seto Inland Sea after the installation. At first, the property of temperatures in the steel pipe of the tide guage is analyzed. The unevenness of temperatures is found, so we construct the algorithm of the correction of the acoustic velocity by using calibration bars. Finally, the improvement of the accuracy is confirmed by observed data.