A third‐generation wave model for coastal regions: 2. Verification

Abstract

Abstract. A third-generation spectral wave model (Simulating Waves Nearshore (SWAN)) for small-scale, coastal regions with shallow water, (barrier) islands, tidal flats, local wind, and ambient currents is verified in stationary mode with measurements in five real field cases. These verification cases represent an increasing complexity in twodimensional bathymetry and added presence of currents. In the most complex of these cases, the waves propagate through a tidal gap between two barrier islands into a bathymetry of channels and shoals with tidal currents where the waves are regenerated by a local wind. The wave fields were highly variable with up to 3 orders of magnitude difference in energy scale in individual cases. The model accounts for shoaling, refraction, generation by wind, whitecapping, triad and quadruplet wave-wave interactions, and bottom and depth-induced wave breaking. The effect of alternative formulations of these processes is shown. In all cases a relatively large number of wave observations is available, including observations of wave directions. The average rms error in the computed significant wave height and mean wave period is 0.30 m and 0.7 s, respectively, which is 10% of the incident values for both. IntroductionThe wave model Simulating Waves Nearshore (SWAN) has been developed by the authors (described by Booij et al. The results of the SWAN computations are presented and compared with the observed significant wave height, mean wave period, and mean wave direction. In addition, a comparison is made between computed and observed spectra. The structure of the paper is as follows. The SWAN model is briefly described in section 2. The verification cases are described in section 3. A quantitative analysis of these verifications is given in section 4. A discussion and the conclusions of this study are given in sections 5 and 6, respectively.•Now at WL/Delft Hydraulics, Delft, Netherlands.

Morphological and sedimentological response of a mixed-energy barrier island tidal inlet to storm and fair-weather conditions

“…The mathematical model solves the three-dimensional shallow-water equations and continuity equation on a staggered model grid by means of an implicit finite-difference scheme. The spectral wave model SWAN Ris et al, 1999) is run in a stationary mode to simulate the wave propagation and deformation from the open sea to the shoreline. Wave measurements available at intervals of 30 min are applied as offshore boundary conditions.…”

Numerical simulation of wind waves on the Río de la Plata: evaluation of four global atmospheric databases

“…SWAN is a numerical wave model that provides realistic estimates of wave parameters in coastal areas RIS et al, 1999). Even though this model was specifically designed for coastal applications, it could be applied to wind generated surface gravity waves on any scale (HOLTHUIJSEN et al, 2004).…”

“…Coastal impacts related to a possible wind wave change on the South-eastern South American Continental Shelf were reported by Dragani et al (2011) and Codignotto et al (2012) who studied trends in mean annual wind wave heights implementing Simulating Waves Nearshore (SWAN, BOOIJ, et al, 1999;RIS et al, 1999) model forced with surface winds from National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) Reanalysis I (KALNAY et al, 1996) in a regional domain which includes the Río de la Plata (RDP) estuary and the adjacent continental shelf. The RDP, located on the eastern coast of southern South America at approximately 35°S ( Fig.…”

The 14th international workshop on wave hindcasting and forecasting and the 5th coastal hazards symposium

“…van Vledder et al (2016) presented a wave hindcast of a severe storm in the Southern North Sea with the objective of assessing recently developed deep and shallow water source terms for use in third-generation wave prediction models. These deep water source terms for whitecapping, wind input and nonlinear interactions were developed, implemented and tested primarily in WW3, whereas shallow water source terms for depth-limited wave breaking and triad interactions were developed, implemented and tested primarily in the SWAN wave model Ris et al (1999) and Booij et al (1999). Their performance and the impact of different physical settings on the prediction of wave heights and wave periods in the relatively shallow North Sea was analysed for the December 2013 storm (which was also investigated by Staneva et al 2017).…”