Oudshoorn (1960), Wills and Beaumont (1971), Evmenov et al (1973) and others have published photographs of a radar scope showing waves. Ijima et al (1964) and Wright (1965) appear to have been among the first to report the use of radar for imaging ocean waves. The location of the radar is shown on the aerial photography by an "X". The image does not show any features of the land. Note the similarity of the wave patterns in the radar image and the aerial photograph. ![]() Several characteristics of the radar images of waves, as compared to aerial photography, are illustrated in Figure 1. The most important disadvantage is that short ripples are essential to the detection of long waves, hence swell is not detected outside the breaker zone when the wind is calm or the high frequency waves are inhibited by oil slicks. It does not provide as much resolution as aerial photography and the shorter waves of interest may be missed. Specifically, the imaging radar does not provide a measure of wave height. Imaging radar, of course, also has some disadvantages when compared to other data gathering systems. ![]() Imaging radar has the advantages of providing full two-dimensional information of the type provided by aerial photography and of being available continuously, including night time and during storms. This is especially important near shore where the effects of refraction and shoaling interfere with the simple interpretation of a directional spectrum based on records from a network of gages. Imaging radar can be used to provide information about the two dimensional character of the wave field.
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