Modern Studies Of Wind Generated Ocean Waves

The goals of wind wave research are relatively well defined: to be able to predict the wind wave field and its effect on the environment. That environment could be natural (beaches, the atmosphere etc.) or imposed by human endeavour (ports, harbours, coastal settlements etc.). Although the goals are similar, the specific requirements of these various fields differ considerably. This book attempts to summarise the current state of this knowledge and to place this understanding into a common frame work. It attempts to take a balanced approach between the pragmatic engineering view of requiring a short term result and the scientific quest for detailed understanding. Thus, it attempts to provide a rigorous description of the physical processes involved as well as practical predictive tools.

This book was published in 2004. The Interaction of Ocean Waves and Wind describes in detail the two-way interaction between wind and ocean waves and shows how ocean waves affect weather forecasting on timescales of 5 to 90 days. Winds generate ocean waves, but at the same time airflow is modified due to the loss of energy and momentum to the waves; thus, momentum loss from the atmosphere to the ocean depends on the state of the waves. This volume discusses ocean wave evolution according to the energy balance equation. An extensive overview of nonlinear transfer is given, and as a by-product the role of four-wave interactions in the generation of extreme events, such as freak waves, is discussed. Effects on ocean circulation are described. Coupled ocean-wave, atmosphere modelling gives improved weather and wave forecasts. This volume will interest ocean wave modellers, physicists and applied mathematicians, and engineers interested in shipping and coastal protection.

The study of sea waves has always been in the focus of mankind's atten tion. This is attributed not only to a desire to understand the behaviour in seas and oceans, but also, it has some practical necessity. Developing up-to date wind wave numerical methods requires detailed mathematical modelling, starting with wave generation, development, propagation and transformation on the surface in different water areas under quasi-stationary conditions, up to a synthesis of climatic features observed under different wave generation conditions in oceans, sea or coastal areas. The present monograph considers wind waves in terms of the most general formulation of the problem as a probable hydrodynamic process with wide spatial variability. It ranges between the global scale of the oceans, whose typical size is comparable with the Earth's radius, to the regional and local scales of the seas, including water areas limited in space with significant current or depth gradients in coastal zones, where waves cease their existence having propagated tens of thousand miles.

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work is in the "public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.

Early in 1979, a group of wave researchers proposed a wave model inter comparison study to clarify the interrelations existing among the various wave models which have been developed in past years for real-time wave forecasting, wave statistics compilations, or hindcast case studies. The idea was immediately welcomed by the wave modeling community, and, finally, nine wave modeling groups from the United States, Japan, and Europe participated in the exercise. The principal results of this work are presented here jointly by the Sea Wave Modeling Project (swAMP) Group (the members of which are listed in Appendix A). Descriptions of the models used in the study are given in Part II of this volume. A more complete documentation of the entire set of numerical experiments is given in Part 2 of the Sea Wave Modeling Project (SWAMP group, 1982). The main purpose of the intercomparison study was to test our present understanding of the physics of . wind-generated surface waves from the viewpoint of wave modeling. Specifically, we wished to clarify the basic interdependence between understanding the physics of surface waves, repre senting the physics numerically, and predicting quantitatively the detailed space-time evolution of a two-dimensional surface wave spectrum for a given wind field. It was not our intent to carry out a model competition. In this sense there were no winners or losers: all models could claim specific strong points, and all displayed weaknesses in some areas.

In this classic study, a renowned student of ocean wave theory examines the data requirements and details of the power spectral analysis required to make the wave revolution intelligible. Although the discussions center on waves, once the techniques are understood, they can be applied to many other areas. After outlining the nature of waves and wave processes and their methods of measurement and classification, the author provides a detailed exploration that relies heavily on mathematical models. Topics include perturbations of irrotational motion, energy considerations, wave generations by wind, and much more. The text is enhanced and clarified by 270 photos, figures, and tables. A helpful bibliography and indexes conclude this indispensable addition to the oceanographer's library.

This volume proposes an integral approach to studying the geophysics of Earth. It is motivated by a variety of phenomena from nature with deep and direct impacts in our lives. Such events may evolve across a large range of spatial and time scales and may be observed in the ocean, the atmosphere, the volcanic surface as well as underground. The physical laws dictating the evolution of such phenomena lead to the unifying theme of this manuscript, that is, the mathematical and computational modeling of flows and waves. Consequently, the underlying models are given in terms of Partial Differential Equations (PDEs) whose solutions are approximated using numerical methods, thus providing simulations of the aforementioned phenomena, as well as the appropriate geophysical validation and interpretation.