Extraction of short wind wave spectra from stereo images of the sea surface

Abstract

A combined method is proposed to estimate the spectra of short wind waves. The spectra extracted from stereo pairs of the sea surface are used for the absolute calibration of the slope spectra obtained with Fourier-processing of the same high-resolution photo images. The calibration extends significantly the range of scales of stereo-retrieved waves toward the shortest ones. The method was adjusted and validated in situ. Algorithms and their experimental validation are presented, covering a range of wavelengths from 30 cm up to 6 mm, for different wind speeds. Spectral shapes and levels are consistent with earlier experimental data and models.