Ocean wave dispersion surface measured with airborne IR imaging system

Image sequences of the ocean have been collected at long range and low grazing angle with an airborne infrared system. The images are geographically registered, and 3D frequency-wavenumber spectra are calculated and shown to have a strong 2D dispersion surface that is characteristic of wind waves and swell. Wave directions compare well with in situ measurements, and their speeds are consistent with the water depth. The authors conclude that temporal sequences of IR images acquired from long distance can provide information for extracting surface wave parameters.