So you might have seen my novel on the formation of sand ripples last week, and the tl;dr: I have a vague idea of how sand ripples form, but it’s not as clear to me as I would like.
But imagine my delight when, after two days of foam stripes like this one…
…there was a distinctly different ripple pattern directly underneath the foam stripe!!!
In some places, there was even a tiny little bit of foam left. Where? Right on top the anomalous stripe in the ripple pattern!!!
So now I still don’t understand what’s going on in the sand, but at least it’s lining up exactly with a phenomenon in the waves that I don’t understand, either! :-D
Sailing out of the Kiel fjord on a large ferry changes the whole perspective on the coastline. For example below, we see the lighthouse Friedrichsort which is located at the end of a headland and which is always an interesting spot for wave watching.
Or on the other side of Kiel fjord, Laboe is very popular with kite surfers. There are sand banks quite far out in the fjord and a very shallow area connecting the sand banks and the beach, so the water is usually calm and warm there.
It’s very interesting to see this not from sea level, but from higher up!
A while ago I wrote a blog post on how the sand banks in this little creek form. Below you see the picture I showed then:
Then, about two weeks ago, I passed that spot again when it was raining, and this is what it looked like:
Now we can actually see the flow field, and we can see that the sand bank in the far back has moved quite a bit. We also see that during the night it must have rained more at some point, since the leaves on the sandbank on the left that got stranded there, must have been carried there by a higher water level.
I went back later that day when it had stopped raining, and then it looked like this:
Now that the water level has sunk again, you can clearly see that the sand banks have shifted compared to where they were in the first picture a couple of weeks ago.
Funny how much you can discover if you actually look at the world around you :-)