Remote and Synoptic Water Wave Measurements by Aerial Photography: A Model, Experimental Results and an Application

This paper briefly reviews the parameters involved in aerial photography of coherent trains of surface waves. This includes the effects of water reflectance, waves, and sun and cloud conditions, on the quality of wave imaging in aerial photos. It also describes an analytical model of the specular reflection of sunlight by surface waves, together with experimental results from an outdoor wave facility. Analytical expressions are derived for the accuracy of wave-length measurements using aerial photos of waves. Further, it treats wave slope determination from aerial photos of ideal waves and presents experimental results from an outdoor wave facility. The application of remote synoptic surface flow determination by imaging of surface waves is briefly discussed.