Statistical Analysis of Longshore Currents on a Barred Beach

Suzuki, T. and Cox, D.T., 2019. Statistical analysis of longshore currents on a barred beach. Journal of Coastal Research, 35(6), 1215–1224. Coconut Creek (Florida), ISSN 0749-0208. Longshore currents were observed using a horizontally mounted acoustic Doppler current profiler in the nearshore on a dissipative barred beach. The data were taken for 20 days from 13 May to 2 June 2016. Wave, current, water level, and wind data were continuously observed. From a statistical point of view, the exceedance probability/occurrence ratio of higher currents is important. Therefore, in this research, the hourly data were used to investigate the spatial and wave-energetic distributions of exceedance probability of the longshore currents. Moreover, the effect of tidal range on this exceedance probability is discussed. From the analysis, the exceedance probabilities of longshore currents were well predicted by the Weibull distribution, with parameters estimated using the normalized wave energy flux, relative surf-zone location, and normalized water depth. The exceedance probability of the longshore current was largely affected by water level (tidal elevation): during high tide it was the same or lower than that of the full data set. However, the exceedance probability was approximately two times larger during low tide than that using the full data set.