Breaking Waves pp 103-108 | Cite as
Microwave Backscattering from Laboratory Wind-Wave Surfaces and its Relation to Wave Breaking with Bubble Entrainment
Abstract
Microwave backscattering from wind-wave surfaces in a wind wave tank is investigated by using an x-band (9.6 GHz) scatterometer. It is found that intensity of the backscattered signature is in phase with the surface displacement. Variation of the Doppler velocity also corresponds to the phase of the individual waves. High Doppler velocity observed at the crests of the individual waves coincides with the propagating speed of the crests. It is concluded that the fine structures of wind-wave surfaces, which are trapped near the crests and are propagating with the crests, mainly contribute to microwave backscattering. It is also shown that the wave breaking with bubble entrainment does not increase the microwave backscattering under the conditions of the present experiment. (This paper is an extended abstract. This study will be published in full elsewhere.)
Keywords
Turbulent Boundary Layer Wind Wave Surface Displacement Wave Breaking Doppler VelocityPreview
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