Kyu YOSHIMORI,¹ Kohzaburo OHNAKA,² Kazuyoshi ITOH,² Hiroshi KAWAMURA³ and Yoshiki ICHIOKA⁴

¹Furuno Electric Co., LTD., Ashihara-cho 9-52, Nishinomiya, 662 Japan, ²Department of Applied Physics, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, 565 Japan, ³Center for Atmospheric and Oceanic Studies, Faculty of Science, Tohoku University, Sendai, 980 Japan, ⁴Department of Material and Life Science, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, 565 Japan

(Received November 28, 1996; Accepted June 10, 1997)

A method for numerical realization of a full gravity-capillary wave surface that is specified by a wave-spectral model and a dispersive relationship of the surface wave is developed on the basis of the angular spectral representation of a random water surface. A significant aspect of the method is that it requires a smaller number of spectral samples than that required by the Whitteker-Shannon sampling theorem for the complete generation of a full gravity-capillary wave surface, without resulting in any appreciable errors in auto-correlation functions for the surface displacement or surface slopes. The method enables the unified treatment of gravity and capillary waves in numerical studies of higher order characteristics of the thermal radiation emitted from, and the light scattered by, the wave surface.

Key words : ocean, rough surface, thermal emission, scattering

yosimori@eorc.nasda.go.jp