Direct production of droplets from breaking wind-waves - its observation by a multi-colored overlapping exposure photographing technique

The micro-scale configurations of the surface of breaking wind-waves and their processes of change were investigated through wind-wave tank experiments, with use of a simple, new photographic technique of multi-colored overlapping exposures. The most conspicuous micro-scale phenomenon was the appearance of small projections, mainly on the crest of the wave and the succeeding stretching and breaking of these projections into small droplets. This sequence of events shows the process of the direct production of droplets by breaking waves. The movements of such directly produced droplets were also measured and their characteristics in relation to the phase of the wave are discussed.