On the distribution of small-scale roughness at the edges of monomolecular surface films

The authors have carried out wind-wave tank measurements of wave slopes, radar backscattering, and video image intensity, while the water surface was covered with small patches of surface-active material. Their results show that, at low wind speed, the slick patches consist of regions of different damping behavior caused by the freshly spread slick. By analyzing the radar Doppler shifts they could show that the distribution of bound and freely propagating waves along a slick patch strongly varies. Since the video camera is less sensitive to the observed small-scale features they support the use of such devices for automated slick detection.