2023 Volume 79 Issue 18 Article ID: 23-18183
The study of wave run-up on sandy beaches is important not only for the beach management, but also for the functional evaluation of shore protection facilities such as seawalls and for disaster prevention in the backshore area. It has been carried out by hydraulic model experiments, numerical models and field observations, but there has been no research method to quantify the time series in wave run-up height on the beach from images taken at the site. In this study, we proposed a method to quantify wave run-up and investigate the temporal variation of maximum run-up height using image analysis for image data taken from January 1 to December 31, 2021 at Wakasa-Wada coast in Japan as an example. As a result, the method was able to calculate the maximum wave run-up height with an error of 0.49 m in the horizontal direction and 0.04 m in the vertical direction in case of a wave height of 2 m, and with an error of 0.49 m in the horizontal direction and 0.02 m in the vertical direction in case of that of 3 m. The results for wave heights of 2 m and 3 m were compared, and it was found that the method could be applied with higher accuracy when wave heights were higher.