Wind-Wave Breaking

Rational models of wind-wave growth were proposed in the 1950s (Miles 1957, Phillips 1957), theories of wave-wave interactions (Phillips 1960, Hasselmann 1962, Zakharov 1968) and wave-action conservation for waves in fluids (Whitham 1965, Bretherton and Garrett 1969) in the 1960s, but it was not until the 1980s that laboratory experiments (Duncan 1981, Melville and Rapp 1985) and a seminal paper by Owen Phillips in 1985 on a model of the equilibrium range in wind-wave spectra, and a formulation of breaking, began a rational program of research into the role of breaking in surface wave kinematics and dynamics. Two important features of Phillips’ 1985 paper were the introduction of Λ(c)dc, the average total length of breaking fronts per unit area of ocean moving with velocities in the range (c, c + dc) and the statement that the average rate of energy loss per unit area by breakers in the same velocity range was given by