F. Ardhuin¹, S. Viroulet¹, J.-F. Filipot¹, A. Benetazzo², V. Dulov³, F. Fedele⁴

¹ Laboratoire d'Océanographie Spatiale, Ifremer, Brest, France

² PROTECNO Srl, Noventa Padovana, Italy

³ Marine Hydrophysical Institute, Sevastopol, Ukraine

⁴ School of Civil and Environmental Engineering, Georgia Institute of Technology, Savannah, USA

Аннотация

The capabilities of a Wave Acquisition Stereo System (WASS) are tested for the measurement of wave spectra. A first experiment with relatively low resolution cameras (2 megapixels) at 12 m height above the sea was conducted on the Marine Hydrophysical Institute platform in the Black Sea in October 2010. The acquisition of a few hours of data allowed testing the performance of the system in moderate wave conditions. The stereo video data is processed using an epipolar method into maps of the sea surface elevation every 0.1s. The retrieved sea surface appears consistent for scales larger than 1 m, and suffers from various processing and discretization errors for the shorter scales. Although the field of view is only about 40 by 40 meters, the analysis of the direction of longer waves can be performed thanks to the linearity of these waves using classical array analysis techniques.

Ключевые слова

wind waves, stereo-video processing, wind wave spectra

Для цитирования

Ardhuin F., Viroulet S., Filipot J.-F., Benetazzo A., Dulov V., Fedele F. Measurement of directional wave spectra using a wave acquisition stereo system: a pilot experiment // Экологическая безопасность прибрежной и шельфовой зон и комплексное использование ресурсов шельфа. 2010. № 21. С. 252–258. EDN WYQVZV.

Ardhuin, F., Viroulet, S., Filipot, J.-F., Benetazzo, A., Dulov, V. and Fedele, F., 2010. Measurement of Directional Wave Spectra Using a Wave Acquisition Stereo System: A Pilot Experiment. Ecological Safety of Coastal and Shelf Zones and Comprehensive Use of Shelf Resources, 21, pp. 252–258.

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