A reader of my blog, Rocío*, sent me this beautiful image from Arnao beach (Castrillón- Asturias-Spain), and I asked if I could use it in a #friendlywaves post. He agreed, so here we go!
First, let’s check out the original image in all its beauty, before I start scribbling on it. What features of the waves stand out to you that you find especially interesting?
For me, what I think is especially awesome here, is how the behaviour of the waves lets you draw conclusions about the sea floor underneath. Look at all the wave crests coming in nice and parallel. Far offshore, it’s difficult to even see wave crests (marked orange, for example), only when they come closer to the shore and the sea gets shallower, they start to build up, get a distinct shape. Yet in some places they become a lot steeper and start breaking a lot further offshore (red marks) than in others — why?
Because in those spots the sea is shallower, thus the interaction with the seafloor is a lot stronger. If you look at the yellow mark, for example: Offshore of it the wave crests are still very shallow and not pointy, and then all of the sudden they break. Here the water is deep until there is a very fast change and then it’s suddenly very shallow (and probably rocky, hence all the turbulence).
And then, if you come closer towards the shore, there is an area that has only a very gradual incline, where the shape of the waves hardly changes any more (blue marks).
And then there is a small inlet to a large puddle that acts as “slit” (albeit a fairly wide one) and lets waves radiate as half circles from where they enter through the slit.
I love how in such a beautiful image of such a beautiful landscape, there is so much physics that we can discover if we only choose to look! :-)
*I asked how I could credit the picture to Rocío, but he doesn’t have Twitter or a website and wrote “I only want you to explain it for people i love your blog and your information you are doing a great job”. Aaaaw, thank you!!! :-) And thanks for sending me this beautiful picture!