Fluorescent sands for measurements of longshore transport rates: a case study from Praia de Faro in southern Portugal

Abstract

A field experiment was carried out on a mesotidal reflective beach to relate longshore sand transport rates to wave measurements in medium-energy conditions (H rms =0.6 m; T m =6.5 sec; α=20°). Dispersion of fluorescent sand tracers was analyzed using the spatial integration method (SIM). The measured sand transport rate was three times larger than the prediction computed using the longshore wave power approach, while the K factor was determined empirically as 2.32. The study concluded that there is a need to calibrate bulk longshore transport predictors before applying them to steep gradient slopes under plunging waves.