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Violante-Carvalho, N.; D'Avila, V.; Heringer Villena, H.H., and Mendonça Filippo, A.M., 2020. The Flying Anchor: An original technique for beach profile measurements in the surf zone. Journal of Coastal Research, 36(3), 654–660. Coconut Creek (Florida), ISSN 0749-0208. An original method is proposed to measure beach profiles in the surf zone. Surveying this dynamic and energetic region is usually a challenge when waves are large, which is exactly when the nearshore processes are more intense. The lack of bathymetry and wave data is indisputably a limiting factor hindering the understanding of the physics involved. Countless techniques have been proposed in the last decades to increase the temporal and spatial density of such measurements, with different degrees of success. Seeking to bring new approaches to address these issues, the proposed operation consists of launching a specially designed anchor from the beach face over the surf zone, carrying a graduated cable. When the cable is drawn taut, a pressure sensor is hand towed along the sea floor measuring the profile, as well as yielding the wave energy spectrum. The technique is efficient and fast and employs a small team at a very low cost. Some of the main limitations of the known in situ techniques, such as sea state dependency, high cost per profile, and longshore drift, are mitigated. [ABSTRACT FROM AUTHOR]

Rapizo, H.; d'Avila, V.; Violante-Carvalho, N.; Pinho, U.; Parente C.E., and Nascimento, F., 2016. Simple techniques for retrieval of wind wave periods and directions from optical images sequences in wave tanks. Optical techniques are potentially suitable for overcoming some of the limitations faced by single-point sensors, like buoys, in retrieving spatial properties of wind-generated waves. However, most of the approaches that have been addressed in the literature employ complex configurations that use a coupling system between cameras, making its implementation difficult. This article describes simple techniques for measuring the period and direction of multimodal, regular waves, employing a single, commonly available camera. Furthermore, there is no special requirement for light conditions, making its implementation feasible, in both indoor and outdoor environments. Several tests were conducted in a multidirectional tank, varying the steepness and direction of the waves. The optical measurements were in good agreement, especially for waves from moderate to greater steepness. The techniques described here could be employed as a preliminary step before tackling more-complex configurations, for instance, as a priori information on the main wave modes. [ABSTRACT FROM AUTHOR]