容量式波高計の改良と現地観測への適用

Abstract

To investigate wave transformation in shallow water, accurate multi-point observations ofwaves have to be carried out in the offshore direction from the shoreline. For this, improve-ment of capacitance-type wave gauges, especially about their electronic circuit of the amplifierand probe sensor is made through detail calibration. Sets of capacitance-type wave gaugeboth for laboratory experiment and field observation are constructed successfully. Applicationof the sets of wave gauges is made to multi-point observations of waves along an observationpier 315 m long in the offshore direction at Ogata coast. Comparison test between thecapacitance- and sonic-type wave gauges is also made. Wave profiles, spectral properties, wave grouping, as well as statistical properties of the observed waves are compared. Weconclude that the improved wave gauge is successefully applicable to field wave observationswith high accuracy and stability. Some informations of transformation of random waves invery shallow water are described.