Архив статей журнала
Purpose. The work is aimed at studying the statistics of width-to-length ratio of a breaking crest for an active phase of wind wave breakings and at assessing the possibility of approximating the geometric shape of a breaking with an ellipse.
Methods and Results. The experimental data including the video records of sea surface and the wind speed measurements were obtained at the stationary oceanographic platform in the Black Sea Hydrophysical Subsatellite Polygon of Marine Hydrophysical Institute (near the village of Katsiveli, the Southern Coast of Crimea) in 2015–2019. Processing the in situ data made it possible to form the arrays both of lengths and areas of the breakings and the synchronous measurements of wind speed.
Conclusions. The distributions of random variables proportional to the minor-to-major axes ratios of breakings are obtained. It is shown that these distributions are coincident for the whitecaps of different scales. This fact testifies to the similarity of breaking geometric shapes. The average value of breaking axis ratio obtained from all the data is 0.41. It is concluded that the average geometric shape of the breaking boundaries is satisfactorily described by an ellipse with eccentricity 0.91. The ratio of the speed of a breaking centroid to that of its anterior front is estimated to be 0.9.