Molkov A.A.
The present paper continues a series of studies on using underwater images of the sky (Snell’s window) to retrieve characteristics of wind-driven waves and their variations in the field of near-surface hydrophysical processes and under influence of surfactant films. Research is based on the previously developed mathematical models of the Snell’s window image and two statistical moments, the Elfouhaily spectrum of wind-driven waves, the Ermakov model of wave damping by a thin film, and the Cox-Munk result for a thick oil film. Varying wind, wave, and film parameters in the numerical experiment, we demonstrated a sensitivity of considered statistical moments to changes in wind-wave conditions and viscoelastic characteristics of films. To distinguish film influence from wind weakening having similar manifestations, a series of real underwater images demonstrating the changes in the spot structure with the passing surfactant film through the observed sea surface area were analyzed. The obtained results demonstrate that presented method can be useful in practice for detecting surfactant films with the help of optical recorders fixed under the buoys, for example.
