Ocean wave height spectra computed from high-altitude, optical, infrared images

Calibrated ocean wave height spectra are derived from Airborne Visible/Infrared Imaging Spectrometer images. A modulation transfer function that relates the ocean surface wave slopes to the at-sensor radiance is developed by extending the Cox and Munk [1954] model to account for image-resolvable waves. Parameters in the transfer function include the atmospheric transmittance and the small-scale wave slope statistics. These parameters are estimated from the change in at-sensor radiance with respect to view angle. The derived transmittance and atmospheric path-scattered radiance are consistent with results obtained from a radiative transfer calculation using a reasonable model for the aerosol loading. The optically measured wave heights agree well with National Oceanic and Atmospheric Administration buoy measurements extrapolated to the image region.