They are called crosswaves.
Large crosswaves like the ones below are very rare and often dangerous to swimmers and shipping alike. They are formed by wave production far out to sea. Usually, but not always, by different and geographically displaced weather systems.
The ones I have seen appeared in tidal pools with incoming waves from the sea and a perpendicular crosswind.
They have a beautiful symmetry to them.
Sipped from here:
By Michel Griffon , CC BY 3.0, Link
Fun thing is, this only happens on 1 place on earth.... France
Exactamente en la Isla de Ré. Aunque también se han visto en las playas de Tel Aviv. Debe ser impresionante vivir esa experiencia.
Also recently been figured out that similar kinds of rare wave and weather phenomena are what gives the bermuda triangle it's reputation.
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