Space-Time Waves and Spectra in the Northern Adriatic Sea via a Wave Acquisition Stereo System

Abstract

A novel Wave Acquisition Stereo System (WASS) is proposed for the stereo reconstruction of oceanic waves both in space and time. To test the performance of such video observational technology, we have deployed WASS at the oceanographic tower Acqua Alta in the Northern Adriatic Sea, off the Venice coast in Italy. The analysis of WASS video measurements yielded accurate estimates of the oceanic sea state dynamics, the associated directional spectra and wave surface statistics that agree well with theoretical models. Further, the expected largest wave surface height over an area is estimated via both Piterbarg’s theory (Piterbarg 1995) and Adler’s Euler characteristics (Adler 1981, Adler and Taylor 2007). It is found that the largest surface height over the imaged area is considerably larger than the maximum crest observed in time at a single point, in agreement with theoretical predictions.