Long-range airborne IR detection of ocean waves

Observations of the open ocean have been collected at long range and low grazing angle with an airborne infrared system. These images are geographically registered using the position of a fiducial object in the scene as the reference. The three-dimensional frequency-wavenumber spectra computed from time histories of these images show a strong two-dimensional dispersion surface that is characteristic of wind waves and swell. The wave directions obtained from the spectra compare well with in situ measurements. Moreover, the wave speeds deduced from the spectra are consistent with the mean water depth in the area imaged. Ocean waves have been measured previously with other sensors, but these observations are believed to be the first measurements of ocean waves with an airborne infrared system.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.