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Almar, R.; Almeida, P.; Blenkinsopp, C., and Catalan, P., 2016. Surf-swash interactions on a low-tide terraced beach. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 348-352. Coconut Creek (Florida), ISSN 0749-0208. Through an integrated approach, this paper investigates the role of coupled surf-swash dynamics on outgoing waves using data collected at a low-tide terraced beach, Grand Popo, Benin (Gulf of Guinea, West Africa). Observed reflection is 8 %. Analyses are conducted from deep water directional wave spectra measurements, daily beach surveys and remote video measurements. Our results show that the swash can be a non-negligible component of the nearshore energy balance (14% of total dissipation) and is closely tied to reflection. Reflection thus depends on waves at swash inception (offshore waves and surf zone saturation), and shoreface slope varying with tide and morphological evolution. An outgoing cut-off frequency (shortest reflected waves) can be linked to swash saturation with a strong dependence on shoreface slope. A phase-resolving Boussinesq model was validated and used to investigate the influence of terrace width, upper shoreface slope and tidal elevation over the terrace. This papers puts forward the role of the coupled system surf-swash and underlines potential key interactions between a rapid shoreface evolution and surf zone hydro-morphodynamics. [ABSTRACT FROM AUTHOR]

Biausque, M.; Senechal, N.; Blossier, B., and Bryan, K.R., 2016. Seasonal variations in recovery timescales of shoreline change on an embayed beach, Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 353-357. Coconut Creek (Florida), ISSN 0749-0208. Video images acquired during ten years (from January 1999 until June 2009) were analyzed to study cross-shore and alongshore variability of the shoreline on an embayed beach at Tairua Beach (New Zealand). Cross-shore landward migrations occur not only due to high energetic events (such as storms), but are a result of a mix of different parameters. In particular the shoreline of embayed beaches experiences rotation events during which opposite accretion and erosion patterns are observed at the extremities of the beach. When the beach is in an unrotated state, the erosion of the shore is accentuated. The notion of dynamic equilibrium between morphology and wave energy is common approach to understanding the drivers of such shoreline variations. Therefore, to quantify erosion and accretion rates, we used an empirical shoreline prediction model. In this application of the model, we showed that seasonality exists in these rates, between austral summer and winter. The difference in these rates could be because of the influence of the beach rotation on recovery periods. Indeed, the winter beach is generally in a more rotated state than the summer beach. [ABSTRACT FROM AUTHOR]