This could be floating debris, such as logs, drawn into the long linear streaks of foam known as “windrows”. These“Langmuir circulations” are counter rotating cells of water, parallel to the wind direction, in which water from two cells converges on the surface before descending, to resurface again as up-wellings between the “rows”. Foam and floating objects are drawn into these “confluences” and so form lines.



(See Shine and Martin 1988 p: 170)

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