One of the most familiar phenomena on the planet, water waves remain an elusive question for science. The way in which wind blows over water and causes waves is a very active area of research for applied mathematicians, as well as for oceanographers and engineers. The basic mechanisms are still a matter of controversy, although the use of modern techniques of asymptotic and non-linear analysis and large-scale computation, as well as experimental structures, are beginning to reveal the underlying mechanics. These studies are resulting in increasingly powerful methods of forecasting waves and of gauging and controlling their effects on such things as sediment, pollution, and offshore structures. This volume covers the wide range of current research on the relationship between wind and waves and includes contributions from many of the leading authorities in the field.

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 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.

Presenting a novel approach to wave theory, this book applies mathematical modeling to the investigation of sea waves. It presents problems, solutions and methods, and explores issues such as statistical properties of sea waves, generation of turbulence, Benjamin-Feir instability and the development of wave fields under the action of wind. Special attention is paid to the processes of dynamic wind-wave interaction, the formation of freak waves, as well as the role that sea waves play in the dynamic ocean/atmosphere system. It presents theoretical results which are followed by a description of the algorithms used in the development of wave forecasting models, and provides illustrations to assist understanding of the various models presented. This book provides an invaluable resource to oceanographers, specialists in fluid dynamics and advanced students interested in investigation of the widely known but poorly investigated phenomenon of sea waves.

A comprehensive 2001 volume for researchers and graduate students in oceanography, meteorology, fluid dynamics and coastal engineering.

The NATO Advanced Research Workshop on Coupling Processes in the Lower and Middle atmosphere held in Loen, Norway in May 1992 was, in the estimation of apparently all participants, an enormous success. The 18 invited speakers included many of the leaders in the field and resulted in the attendance of a large number of contributing speakers and observers. The subject of the workshop was itself very timely, given the increasing awareness within the international community of the sensitivity of the atmosphere to coupling between adjacent layers, different latitudes, and various scales of motion. It was also very beneficial to bring together researchers with different approaches to the same or similar problems. For example, experimentalists benefitted from the inputs of modelers and theoreticians concerning the needs of current models and the most pressing problems and unknowns. Likewise, theoreticians were challenged to apply themselves to realistic problems and saw their theories tested against geophysical data. These discussions led to meaningful exchanges of ideas and challenges to or displacement of conventional wisdom in some areas. Indeed, possibly the greatest benefit of the workshop was the exposure of many participants to other areas of research or approaches to problems relevant to their own work. Workshop topics were confined to dynamical coupling processes in order to examine progress in a relatively focussed area. Nevertheless, the results presented spanned spatial scales from molecular to global and temporal scales from seconds to decades.

Perturbation electric and magnetic fields carry in excess of 10(exp10) to 10(exp12) W of electrical power between the magnetosphere and high-latitude ionosphere. Most of this power is generated by the solar wind. The ionosphere at large spatial and temporal scales acts as a dissipative slab which can be characterized by its height-integrated Pedersen conductivity sigma p, so that the power flux into the ionosphere due to a quasi-static electric field E is given by sigma (pE2) The energy transferred to the ionosphere by time-varying electromagnetic fields in the form of Alfven waves is more difficult to calculate because density and conductivity gradients can reflect energy. Thus, field resonances and standing wave patterns affect the magnitude and altitude distribution of electrical energy dissipation. We use a numerical model to calculate the frequency-dependent electric field reflection coefficient of the ionosphere and show that the ionosphere does not behave as a simple resistive slab for electric field time scales less than a few seconds. Time variation of spacecraft-measured high-latitude electric and perturbation magnetic fields is difficult to distinguish from spatial structuring that has been Doppler-shifted to a non-zero frequency in the spacecraft frame. However, by calculating the frequency-dependent amplitude and phase relations between fluctuating electric and magnetic fields we are able to show that low frequency fields (