Waves change their direction because of changes in water depth

When waves run up a beach, they change their direction because for shallow water waves, phase speed depends on water depth (see this post for a nice little visualization for why the whole wave crest swings in towards the beach).

Unfortunately, it is really difficult to take good pictures of this phenomenon, but I tried:


See below for an annotated version that shows the wave crests:

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It is easier to see in a movie, so here you go with a movie from that exact same spot:

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