A third-generation numerical wave model to compute random, short-crested waves in coastal regions with shallow water and ambient currents (Simulating Waves Nearshore (SWAN)) has been developed, implemented, and validated. The model is based on a Eulerian formulation of the discrete spectral balance of action density that accounts for refractive propagation over arbitrary bathymetry and current fields. It is driven by boundary conditions and local winds. As in other third-generation wave models, the processes of wind generation, whitecapping, quadruplet wave-wave interactions, and bottom dissipation are represented explicitly. In SWAN, triad wave-wave interactions and depth-induced wave breaking are added. In contrast to other third-generation wave models, the numerical propagation scheme is implicit, which implies that the computations are more economic in shallow water. The model results agree well with analytical solutions, laboratory observations, and (generalized) field observations.

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A third-generation wave model for coastal regions: 1. Model description and validation

1. Introduction 2. Observation techniques 3. Description of ocean waves 4. Statistics 5. Linear wave theory (oceanic waters) 6. Waves in oceanic waters 7. Linear wave theory (coastal waters) 8. Waves in coastal waters 9. The SWAN wave model Appendices References Index.

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Waves in Oceanic and Coastal Waters

Circulation, exchange and water masses at the ocean margin: the role of physical processes at the shelf edge

Understanding sea-level processes, such as ocean tides, storm surges, tsunamis, El Nino and rises caused by climate change, is key to planning effective coastal defence. Building on David Pugh's classic book Tides, Surges and Mean Sea-Level, this substantially expanded, full-colour book now incorporates major recent technological advances in the areas of satellite altimetry and other geodetic techniques (particularly GPS), tsunami science, measurement of mean sea level and analyses of extreme sea levels. The authors discuss how each surveying and measuring technique complements others in providing an understanding of present-day sea-level change and more reliable forecasts of future changes. Giving the how and the why of sea-level change on timescales from hours to centuries, this authoritative and exciting book is ideal for graduate students and researchers in oceanography, marine engineering, geodesy, marine geology, marine biology and climatology. It will also be of key interest to coastal engineers and governmental policy-makers.

Sea-Level Science: Understanding Tides, Surges, Tsunamis and Mean Sea-Level Changes

Importance of wave age and resonance in storm surges: The case Xynthia, Bay of Biscay

The effect of a wave-dependent drag coefficient on the generation of storm surge in the North Sea is studied. To this end, a barotropic storm surge model is driven by stress that explicitly depend on the ocean waves. To estimate the effects of waves on the boundary layer the theory of Janssen is used. In this theory the aerodynamic drag depends on the fraction of the stress carried by the waves. For waves limited in growth by time, fetch, or depth this gives an enhancement of the drag. The importance to surges of radiation stress is also investigated. The coupled wave and storm surge models have been tested for three recent storm periods. The calculations with a Smith and Banke stress relation underestimate the surges by 20%. The calculations with the wave-dependent drag give a significant improvement. When corrected for the effects of an external surge, the storm surge caused by a fast moving depression was overestimated slightly. In this case, the generation of the storm surge was dominated by ...

C. Mastenbroek

Papers

The dynamical coupling of a wave model and a storm surge model through the atmospheric boundary layer