Surface gravity wave statistics from stereo video
Date
2013
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Delaware
Abstract
A stereo imaging system was deployed during a 2010 field experiment aboard
R/P FLIP to study small scale surface gravity waves under a wide range of conditions. A novel variational and cross correlation based algorithm is presented which generates 3-dimensional depth maps of the ocean surface from stereo digital video images. This thesis details the hardware and software used in this investigation and characterizes the wave field in space and time. Waves ranging from approximately 5cm < [lambda] < 2m are resolved propagating through the 4m x 4m camera footprint. Good agreement is shown with optical wave-gauge data. Spectral statistics show good agreement with other investigations at similar scales. The surface height frequency spectrum is of the form f-4, while the omnidirectional wavenumber spectrum is shown to be of the form k-3. Peak-wave phase-averaged variances are then presented for distinct wavenumber bands, showing a propensity for small waves to group at long-wave crests.