@article{wiechen_rutten_vries_tissier_mieras_anarde_baker_reniers_mol_2024, title={Measurements of dune erosion processes during the RealDune/REFLEX experiments}, volume={11}, ISSN={["2052-4463"]}, DOI={10.1038/s41597-024-03156-9}, abstractNote={Abstract Nearshore hydro- and morphodynamic data were collected during a field experiment under calm conditions, moderate conditions, and storm conditions with dune erosion in the collision regime. The experiment was conducted on the Sand Engine near Kijkduin, the Netherlands, from October 18, 2021, to January 7, 2022. Two artificial unvegetated dunes were constructed just above the high water line to measure storm erosion and dune impacts from higher water levels and waves. During the experiment, three storms occurred that resulted in significant erosion of both dunes. The collected hydrodynamic data include pressure sensor and velocimeter data along two cross-shore transects. The collected morphodynamic data include bathymetry and topography surveys, optical backscatter sensor data in the inner surf zone, and a continuous cross-shore line-scanning lidar data set of the dune face. This comprehensive data set can be used to (1) study relevant nearshore hydrodynamic and morphodynamic processes that occur during calm conditions, moderate conditions, and storm conditions with dune erosion in the collision regime, and (2) validate existing dune erosion models.}, number={1}, journal={SCIENTIFIC DATA}, author={Wiechen, Paul and Rutten, Jantien and Vries, Sierd and Tissier, Marion and Mieras, Ryan and Anarde, Katherine and Baker, Christine and Reniers, Ad and Mol, Jan-Willem}, year={2024}, month={Apr} }
 @article{baker_moulton_palmsten_brodie_nuss_chickadel_2023, title={Remotely sensed short-crested breaking waves in a laboratory directional wave basin}, volume={183}, ISSN={["1872-7379"]}, DOI={10.1016/j.coastaleng.2023.104327}, abstractNote={Short-crested breaking waves that result from directionally spread wave conditions dissipate energy and generate turbulence within the surf zone, altering sediment transport processes, wave runup, and forces on structures. Additionally, vertical vorticity generated near crest ends during breaking, which depends on the gradient in wave height along a crest, may enhance nearshore dispersion of pollutants, nutrients, and larvae. Although directionally spread irregular wave fields are ubiquitous on ocean and large lake coastlines, the dependence of short-crested breaking wave characteristics (including the along-crest length and number of crest ends) on offshore wave conditions is not well established. To assess this relationship, laboratory experiments with alongshore-uniform barred bathymetry were performed in a large-scale directional wave basin. A three-dimensional scanning lidar, trinocular camera stereo processing methods, and in situ measurements were used to study short-crested wave field breaking characteristics in the laboratory, yielding a dataset with dense spatio-temporal coverage relative to prior laboratory or field measurements. Wave height estimates are similar for remotely sensed and in situ observations, except in the outer surf zone where plunging breaking occurred. Directional wave properties estimated with an array of in situ or remotely sensed sea-surface elevation estimates are similar and yield smaller directional spreads than single-point colocated pressure and velocity based in situ estimates when waves are less directionally spread. Using a breaking crest identification procedure combining visible imagery and stereo sea-surface elevation, we find that the average along-crest length of breaking waves decreases and the average number of crest ends increases with increasing directional spread. Relative to observations, a parameterized relationship between directional spread and crest characteristics based on theory for non-breaking, refracting waves generally over-estimates breaking crest lengths and is similar to or underestimates the total number of crest ends observed in the surf zone. The wave-field-dependent breaking-wave characteristics examined in the laboratory with remote sensing techniques can inform future investigations of depth-limited short-crested wave breaking and resulting surfzone eddy processes.}, journal={COASTAL ENGINEERING}, author={Baker, Christine M. and Moulton, Melissa and Palmsten, Margaret L. and Brodie, Katherine and Nuss, Emma and Chickadel, C. Chris}, year={2023}, month={Aug} }
 @article{baker_moulton_chickadel_nuss_palmsten_brodie_2023, title={Two-dimensional inverse energy cascade in a laboratory surf zone for varying wave directional spread}, volume={35}, ISSN={["1089-7666"]}, DOI={10.1063/5.0169895}, abstractNote={Surfzone eddies enhance the dispersion and transport of contaminants, bacteria, and larvae across the nearshore, altering coastal water quality and ecosystem health. During directionally spread wave conditions, vertical vortices (horizontal eddies) are injected near the ends of breaking crests. Energy associated with these eddies may be transferred to larger-scale, low-frequency rotational motions through an inverse energy cascade, consistent with two-dimensional turbulence. However, our understanding of the relationships between the wave conditions and the dynamics and energetics of low-frequency surfzone eddies are largely based on numerical modeling. Here, we test these relationships with remotely sensed and in situ observations from large-scale directional wave basin experiments with varying wave conditions over alongshore-uniform barred bathymetry. Surface velocities derived with particle image velocimetry were employed to assess the spatial scales of low-frequency surfzone eddies and compute structure functions with alongshore velocities. Second-order structure functions for directionally spread waves (σθ≥10°) are consistent with energy flux to larger or smaller length scales, while normally incident, unidirectional waves do not display this behavior. Third-order structure functions suggest that the surfzone flows exhibit a bidirectional energy cascade—a direct cascade to smaller and inverse cascade to larger length scales—during large directional spreads waves (σθ≥18°). However, there is not decisive evidence of an inverse energy cascade for moderate directional spreads (σθ=10°). Energy flux varies by cross-shore location and increases with increasing directional spread and wave height. Eddy decorrelation length scales weakly depend on wave directional spread. These findings advance our understanding of the dynamics linking wave breaking to large-scale rotational motions that enhance mixing and lead to rip currents, important conduits for cross-shore material exchange.}, number={12}, journal={PHYSICS OF FLUIDS}, author={Baker, C. M. and Moulton, M. and Chickadel, C. C. and Nuss, E. S. and Palmsten, M. L. and Brodie, K. L.}, year={2023}, month={Dec} }