Part one gives a description of the characteristics of the wind field over the ocean, including wind shear, turbulence and coherence. It shows how these parameters are modeled and used as an input to wind turbine analyses. The long-term statistics of the mean wind speed are discussed as well as the most common principles for wind speed measurements. In part two, the kinematics and dynamics of ocean waves are given in a form which in subsequent chapters is used in computing wave loads on structures, both in time and frequency domain. Long- and short-term wave statistics are discussed.

Most dune sand is transported close to the surface by saltation and reptation of grains. The shearing action of the wind is resisted by grain size and shape, bed slope, moisture content, and surface roughness elements (especially the presence of vegetation). The relations between sand flux, particle size, aerodynamic roughness, slope, and wind shear velocity are complex, especially on dune surfaces, and may depart significantly from estimates derived from transport equations. The formation of wind ripples is intimately associated with the transport of sand by saltation and reptation, but the relationships between grain transport processes and the formation and development of ripples are complex, leading to a self-organizing pattern that responds rapidly to changes in sand flux and wind speed.

The concepts of sea state and of short-term and long-term statistics are introduced. Wave by wave and spectral analyses are described; definitions are given of wave spectrum, significant wave height, mean wave period, and narrowness parameter. Theoretical distributions of wave heights (the Rayleigh law) are derived. The concept of return period is introduced. The other environmental parameters considered are the wind, the current, the internal waves, and the marine growth. The different definitions of mean wind velocity are explained. Typical wind profiles and wind spectra are presented.