Numerical Investigation of Spectral Evolution of Wind Waves. Part I: Wind-Input Source Function

This paper is dedicated to the investigation and calibration of the parameterized form for the wind-input source term Si,, proposed earlier on the basis of field observations at Lake George, Australia. The main objective of this study was to obtain spectral forms for the wind-input source function S-in, which incorporates the novel observation-based features and at the same time satisfies the important physical constraint that the total integrated wind input must agree with independently observed magnitudes of the wind stress. Within this approach, a new methodology, a dynamic self-adjusting routine, was developed for correction of the wind-input source function S-in. This correction involves a frequency-dependent adjustment to the growth rate gamma(f), based on extrapolations from field data. The model results also show that light winds require higher-rate adjustments of the wind input than strong winds.