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Passarella, M.; De Muro, S.; Ruju, A., and Coco, G., 2018. An assessment of swash excursion predictors using field observations. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1036–1040. Coconut Creek (Florida), ISSN 0749-0208. Accurate predictions of swash excursion are fundamental for improving the understanding of swash zone dynamics and for coastal management and hazard applications. Researchers have provided several formulas for predicting the swash excursion on sandy beaches. However, the problem of the universality of these formulas is still open. In fact, it is not clear whether the existing formulations are applicable to a wide range of beaches and wave conditions. This study verifies 13 existing swash (total, incident and infragravity) formulations using 13 published experiments (636 swash measurements). The experiments were carried out on beaches worldwide (dissipative intermediate and reflective) under a wide range of wave conditions (including extreme events). Results show that formulas behave differently with under and over prediction. However, some trends can be recognized, which are indeed critical for coastal hazards and management applications: generally, for large swash events (swash >1.5 m) large scatter are found for all formulas. During extreme conditions (swash>2.5 m) total and incident swash are strongly underestimated, while infragravity swash varies for each formula. The maximum errors and the root mean square errors can exceed 2.5 m and 1 m, respectively. [ABSTRACT FROM AUTHOR]

Zhou, Z.; Chen, L.Y.; Townend, I.; Coco, G.; Friedrichs, C., and Zhang C.K., 2018. Revisiting the relationship between tidal asymmetry and basin morphology: A comparison between 1D and 2D models. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 151–155. Coconut Creek (Florida), ISSN 0749-0208. Tidal basin morphology is strongly dependent on the condition of tidal asymmetry which may result in either net import (flood-dominance) or export (ebb-dominance) of sediment. Based on the one-dimensional (1D) shallow water equations, various stability relationships have been developed linking tidal parameters with basin geometry. This study revisits the widely used numerical stability relationship developed by Friedrichs and Aubrey (1988), using a 2D depth-averaged model which is able to describe a more extensive flow field and more realistic bathymetries. Model comparison between 1D and 2D models indicates that excluding or including intertidal areas as a momentum-conveying component can highly affect the tidal velocity distribution and magnitude, particularly when the relative water depth is large (i.e., the ratio between tidal amplitude and mean water depth is small). Meanwhile, the tidal distortion parameters (relative tidal phase 2M2-M4 and tidal amplitude ratio M4/M2) derived from the 2D model appear to be more strongly controlled by the relative water depth (a/h) than that in the 1D model. Further research can be devoted to developing more generic stability relationships which can be applied in a more quantitative manner. [ABSTRACT FROM AUTHOR]