January 15, 2009
While eating lunch at a restaurant overlooking a marina on Lake Norman, North Carolina, I noticed these rippled reflections breaking off into closed loops. Unfortunately, they were some distance away, but I took several pictures to try and get the best representation of this phenomenon. You can just make out the waves from a small boat producing these loops at the top of the picture. These rings are similar in some respects to the moon circles discussed by Dave Lynch in the Earth Science Picture of the Day for December 31, 2007, except that these wave loops weren't taken as time exposures. This was unnecessary given that the waves were of low frequency and pretty much unidirectional, compared with a standard glitter path. However, the reason for the formation of loops is undoubtedly related to the fact that the waves were not perfectly unidirectional. Photo taken in July of 2008.