Working on our own affordable rotating table for oceanographic experiments!

Inspired by the article “Affordable Rotating Fluid Demonstrations for Geoscience Education: the DIYnamics Project” by the Hill et al. (2018), Joke, Torge and I have been wanting to build an affordable rotating table for teaching for a while now. On Saturday, we met up again to work on the project.

This post is mainly to document for ourselves where we are at and what else needs to happen to get the experiments working.

New this time: New rotating tables, aka Lazy Susans. After the one I’ve had in my kitchen was slightly too off-center to run smoothly, we bought the ones recommended by the DIYnamics project. And they work a lot better! To center our tank on the rotating table and keep it safely in place, we used these nifty LEGO and LEGO Duplo contraptions, which worked perfectly.

We also used a LEGO contraption to get the wheel close enough to drive the rotating table. The yellow line below shows where the rim of the rotating table’s foot needs to sit.

And this is how the engine has to be placed to drive the rotating table.

First attempt: Yes! Very nice parabolic surface! Very cool to see time and time again!

Now first attempt at a Hadley cell experiment: A jar with blue ice is placed at the center of the tank. Difficulties here: Cooling sets in right away, before the rotating tank has reached solid body rotation. That might potentially mess up everything (we don’t know).

So. Next attempt: Use a jar (weighted down with stones so it doesn’t float up) until the tank has reached solid body rotation, then add blue ice water

Working better, even though the green dye is completely invisible…

We didn’t measure rotation, nor did we calculate what kind of regime we were expecting, so the best result we got was “The Heart” (see below) — possibly eddying regime with wavenumber 3?

Here is what we learned for next time:

  • use better dye tracers and make sure their density isn’t too far off the water in the tank
  • use white  LEGO bricks to hold the tank in place (so they don’t make you dizzy watching the tank)
  • measure the rotation rate and calculate what kind of regime we expect to see — overturning or eddying, and at which wave number (or, even better, the other way round: decide what we want to see and calculate how to set the parameters in order to see it)
  • use white cylinder in the middle so as to not distract from the circulation we want to see; weigh the cylinder down empty and fill it with ice water when the tank has reached solid body rotation
  • give the circulation a little more time to develop between adding the cold water at the center and putting in dyes (at least 10 minutes)
  • it might actually be worth reading the DIYnamics team’s instruction again, and to buy exactly what they recommend. That might save us a lot of time ;-)

But: As always this was fun! :-)

P.S.: Even though this is happening in a kitchen, I don’t think this deserves the hashtag #kitchenoceanography — the equipment we are using here is already too specialized to be available in “most” kitchens. Or what would you say?

Opening speech for Wlodek Brühl’s art

You might remember that I had the honour of giving a speech at the opening of Wlodek Brühl’s art exhibition back in spring. Preparing my presentation for the Science in Public conference in Manchester next week (that I am immensely looking forward to!), I noticed I never posted the speech. Below is what I sent Wlodek in advance to prepare him for what I might say:

Lieber Wlodek, sehr geehrte Damen und Herren,

es ist mir eine große Ehre, die einleitenden Worte auf dieser Vernissage, dieser Eröffnung der Ausstellung von Werken Wlodek Brühls, zu sprechen und Sie hier Willkommen zu heißen.

Obwohl genau das die Wortbedeutung von „Laudatio“ist, ist mir ausdrücklich untersagt worden, den Künstler zu loben – vom Künstler selbst. Also werde ich heute lieber über Physik sprechen. Wenn Sie die Bilder von Herrn Brühl betrachten, denken Sie dann nicht auch sofort und unausweichlich über Physik nach?

Springbrunnen kennen wir zu Genüge, in Pfützen fallende Tropfen auch. Und letztendlich sehen wir hier genau das, wenn auch mit etwas mehr technischem Aufwand umgesetzt, um die entstehende Skulptur ganz genau beeinflussen zu können. Deshalb kommen uns die in diesen Fotografien gezeigten Formen seltsam vertraut vor – richtig gesehen haben wir sie aber noch nie. Auch wenn genau solche Strukturen um uns herum existieren (und dabei ist anzumerken, dass jede dieser Skulpturen einzigartig ist, wie auch keine Schneeflocke exakt einer anderen gleicht), mit bloßem Auge können wir sie nicht erkennen, weil sie nur für Bruchteile von Sekunden bestehen und unser Gehirn schlicht zu langsam dafür ist. Solche Skulpturen trotzdem bildlich festzuhalten gelingt mit vielen technischen Tricks: Mit computergesteuerten Ventilen, die Tropfen so auslösen, dass sie genau mit anderen Ventilen, dem Blitzlicht zur Beleuchtung und dem Auslöser der Kamera abgestimmt sind. Sichtbar werden dann Skulpturen und nicht nur verwischtes Wasser, weil die Skulpturen in einem stockdunklen Raum für ein Bruchteil einer Sekunde von einem Blitz beleuchtet werden, so dass trotz der längeren Belichtungszeiten der Kamera auf dem Bild nur dieser eine, enorm kurze Moment sichtbar wird, in dem es – exakt zum richtigen Augenblick – geblitzt hat.

Aber kommen wir zur Physik. Wenn Sie diese Ausstellung bei – aus physikalischer Sicht – einfacheren Bildern anfangen und sich dann langsam steigern möchten, würde ich empfehlen, in diesem Raum zu beginnen.

My picture of art by Wlodek Brühl, taken and published with kind permission.

Hier drängt sich mir zum Beispiel die Frage auf, warum die Skulpturen von unten aus dem Wasser nach oben zu wachsen scheinen, bevor sie sich ausbreiten, verzweigen? Der Schlüssel hier ist die Oberflächenspannung des Wassers. Die Wasseroberfläche, durch einen fallenden Tropfen nach unten ausgelenkt, schleudert den Tropfen wie ein Trampolin wieder nach oben und wölbt sich selbst hinterher, bäumt sich auf, bevor sie wieder in sich zusammen fällt. In einigen der Bildern kann man diesen nach oben geschleuderten Tropfen sogar noch erkennen.

My picture of art by Wlodek Brühl, taken and published with kind permission.

Und dann sehen wir im oberen Teil vieler der Skulpturen Formen, die wie Schirme oder Leselampen aussehen, oder wie Vasen. Warum sind diese Strukturen manchmal nach oben geöffnet, manchmal nach unten, manchmal voller filigraner kleiner Ärmchen am Rand? Das sind eigentlich schon zwei Fragen in einer. Die Form der Kelche hängt davon ab, wie schnell sich zwei Tropfen aufeinander zu bewegen und ob ein großer auf einen kleinen trifft oder umgekehrt. Die kleinen Ärmchen sind Instabilitäten, die entstehen, kurz bevor der Schirm zerfällt. Schirme ohne Ärmchen sind also genau in dem Moment belichtet und eingefangen worden, als noch alles stabil war. Bruchteile von Sekunden später wären auch sie instabil geworden.

My picture of art by Wlodek Brühl, taken and published with kind permission.

Und wenn Sie mit diesem Blick durch diese Ausstellung gehen, werden Ihnen noch viele andere Fragen kommen. Manchmal, zum Beispiel, sehen wir Skulpturen, die auf zwei Säulen zu ruhen scheinen. Wie sind diese wohl entstanden? Und dann sind die Skulpturen farbig – und die Farben sind direkt in der Aufnahme entstanden und nicht nachträglich digital eingefärbt. Das wurde in diesem Raum durch farbige Blitze gemacht, in den anderen beiden Räumen durch eingefärbtes Wasser.

My picture of art by Wlodek Brühl, taken and published with kind permission.

Wenn Sie als nächstes dann in den Raum dort hinten weitergehen, sehen Sie Skulpturen, die an der Wasseroberfläche gespiegelt sind. Durch die Spiegelung hat man auf ein mal zwei unterschiedliche Perspektiven auf die Skulptur und kann jetzt Strukturen noch genauer beobachten, um über sie nachzudenken.

My picture of art by Wlodek Brühl, taken and published with kind permission.

Im dritten Raum sehen Sie die neuesten Kunstwerke von Herrn Brühl, die vor wenigen Wochen erst entstanden sind. Hier wird die Physik noch komplexer. Zusätzlich zu all dem, was ich gerade schon über fallende Tropfen erzählt habe, kommen hier noch mit Druckluft angetriebene Fontänen hinzu. Und zwar einfache, die in der Mitte der Skulptur gerade nach oben schießen, und dann auch solche, die aus einer sich drehenden Turbine nach oben und außen geschleudert werden, erst einen Kelch bilden und dann in einzelne Tentakel zerfallen. Und in diesen Bildern sieht man manchmal auch die Schlieren und Pigmente der verwendeten Farben!

Wenn man wollte, könnte man an jedem einzelnen Kunstwerk stundenlang beobachten, grübeln und diskutieren. Wie sähe eine Skulptur wohl aus, wenn ein Tropfen größer gewesen wäre als er war, oder etwas später gefallen, oder vielleicht aus einer anderen Höhe? Oder wenn das Bild Sekundenbruchteile eher oder später gemacht worden wäre und uns damit einen anderen Zeitpunkt der Entwicklung und des Zerfalls der Skulptur gezeigt hätte? Was, wenn anstelle von Wasser zum Beispiel mit Honig gearbeitet würde? An Ihren Gesichtern sehe ich, dass diese Fragen Sie schon jetzt faszinieren. Das ist genau die Physik, die ich speziell bei den Tropfenskulpturen von Herrn Brühl so fesselnd und aufregende finde!

Ich wünsche Ihnen viel Spaß in dieser Ausstellung – dass Sie die beeindruckende Kunst von Herrn Brühl als Kunst genießen können, aber dass Sie sich vielleicht an manchen Stellen auch fragen, wie genau er es wohl geschafft hat, solch ein Meisterwerk entstehen zu lassen. Ich bin mir sicher, dass Herr Brühl Ihnen gerne Rede und Antwort stehen wird! In diesem Sinne: Herzlich Willkommen!

Some #friendlywaves from Berlin

My friend Alice is currently in Berlin, and as one does when visiting Germany’s capital city: She’s wave watching!

I can only say: I approve! That’s what I always do there, too (exhibit 1, exhibit 2).

And knowing that I always like the challenge, she sent me a #friendlywaves picture. Meaning a picture of waves that she would like me to explain.

We aim to please… So here we go! (gif of the original Insta story above, individual pictures for easier viewing below)

Clearly this was done as an Instagram story and not designed to be posted on my blog, and I am not quite sure if it works. Please let me now what you think!

Melting ice cubes experiment published in kids’ journal Frontiers Young Minds

On publishing in a journal peer-reviewed by kids, and suggesting it as a first journal new PhD students should be asked to write for

You guys might remember my favourite experiment with the ice cubes melting in freshwater and saltwater. This experiment can be used for almost any teaching purpose (Introduction to experimenting? Check! Thermohaline circulation? Check! Lab safety? Check! Scientific process? Check! And the list goes on and on…) and for any audience (necessary observation skills start a taking the time it takes ice cubes to melt in the easiest case, to observing the finest details of the melt). In short, I love this experiment!

A different format of science communication

After using it in all kinds of settings for years, I wrote up the experiment for Frontiers Young Minds, a journal which is written for, and peer-reviewed by, kids (link to my article). I love the idea of not only tailoring your science communication to the audience of young readers, but making sure that it actually works well for them by including them in the process. Additionally, the peer-reviewers get a great insight into how a publishing process (and thus an important step in science) works, too.

The whole peer-review and publication process was a really positive experience. Speciality chief editor for “Earth and its resources“, Mark Brandon, and the whole team were super responsive and helpful all the way from initial article idea until publication.

Writing for and being peer-reviewed by young readers

Having my writing peer-reviewed by the “young readers” was super interesting. For example, on one of my articles, they commented on how, as kids growing up in the US, they were not familiar with metric units and could I please give them units they could actually relate to? This is an issue I should probably have been aware of, but I totally wasn’t.

Another example from the other article: a different young reader commented that English was their second language, and could I replace difficult words like “puddle” and “dye” with easier words. As a non-native English speaker myself, this feedback was super helpful — I thought that I was writing in an easy language already, but clearly my perception of “easy language” has drifted into specialized vocabulary — super valuable feedback!

And then both teams reviewing both my articles had a science mentor helping them, and also commenting him/herself on the article and how the review process with the kids went and suggesting further edits, that would make it easier for kids to work with the article.

Illustration by Jessie Miller for Frontiers Young Minds, used with permission

And then, of course, there are Jessie Miller‘s super cute illustrations! After seeing what she did for my first article, I couldn’t wait to see what would happen for this one, and I am super excited about another illustration that makes me feel completely understood and seen.

Writing your first ever article for FYM?

So all in all, publishing with FYM is something I would totally recommend to anyone. And I would even go so far as to recommend it as the first article that PhD students should be asked to write. Why?

  • Articles for FYM can be written on “core concepts”, which can mean basically writing a literature review on the topic you are about to write a PhD thesis on, and one that is broken down so far that you will really have to have understood things. There is this saying attributed to basically all science educators in one form or another, that only if you can explain your topic to a child, do you actually understand it yourself. So explaining to children is actually a super helpful step in the process of getting into a topic yourself.
  • Writing something that is designed to be understood by a wide variety of audiences is really useful for another reason, too: to give to all your family and friends as an easy insight into what it is you are spending all your time on.
  • The feedback you get on how you talk about your topic will be helpful for all future communications about it; Practicing scicomm as early as possible is always a good idea :-)
  • Having a really positive publishing experience is a great start into a PhD, because surely other kinds of experiences will follow sooner or later. The submission through the uploads and forms and stuff works the same way for FYM as for all other journals (including the “oh crap, they want the images in a different format than I prepared them in! Let’s google how to convert them”, “Really? They need an abstract? Maybe I should have read the instructions more carefully…”, or “They are really counting the words on the submission! So now I need to cut an extra paragraph that I thought I could get away with…” surprises that are typical for the “Let me quickly submit this article and go for lunch! Oh wait, half a day later and I am still nowhere near the end of the process” experience that is so common when submitting articles. At the same time, the stakes feel a little lower for this kind of article, since as an early PhD student, you are writing about other people’s work, not yet your own (at least when writing a core concept article, there is also the “cutting edge research” article type, in which you are writing about some newly published article of yours). And then, as I described above, the whole process is really positive and friendly and supportive throughout, even though all the steps are the same as for any other journal (Waiting for the editor to send the article out to the reviewers. Seeing that stuff is waiting on a desk somewhere and compulsively checking every day whether it has been moved on and the email notification just didn’t make it through. Replying to a reviewer. That kind of things). So I believe that it’s a really good way to be introduced to the publishing process without being pushed into super cold water right away, building up confidence for later submissions of your own work.
  • FYM announces new articles on their social media (with lovely tweets!), which have a fairly wide reach, well above what most of us have, and that’s a great opportunity to be seen as authority on a topic by a large number of potentially interested people. Great opportunity to expand your network!
  • And, as I said before, I just love the illustrations and I would imagine that having something like this when you start working on a new topic would be super exciting and motivating :-)

What do you think? Will you suggest writing a FYM article to all your new PhD students now?

P.S.: Here are the links to my FYM articles again: “How does ice form in the sea?” and “When Water Swims in Water, Will it Float, or Will it Sink? Or: What Drives Currents in the Ocean?“.

Experimenting with Insta stories for my wave watching scicomm

Inspired by the absolutely brilliant job that Kati is doing for my project GEO-Tag der Natur, I have recently started experimenting with “Insta stories” on the topic of wave watching.

Insta stories, for those who aren’t familiar with them, are a special type of post on Instagram that only stays visible for 24 hours (unless you save them as highlight, in which case they can be watched until you decide to delete them). They are usually used to give quick glimpses into what’s going on that day, and can be anything from random snap- or screen shots to elaborate stories. The latter is what Kati has been doing for GEO-Tag der Natur — she tells cute and engaging short stories about different topics, using photos and video clips, which she combines with fun gifs to make them even cuter (if you have an Instagram account you can watch them in the highlights of our account).

So that’s what I have been trying to do, too.

My first attempt is posted below — except that what I post below doesn’t contain the links and gifs and stuff, because it turns out that while you can export stories from Instagram, I couldn’t convert them into a format that my blog or vimeo would accept and still keep the gimmicks (original version here). But I still like the format of telling a story. What do you think?

The feedback I got on that story was super positive, so I decided to do it again.

Since my second Insta story contained so many cute gimmicks, I didn’t even attempt to export it, but wrote a separate blog post using the same videos and pictures (But you can watch the story — including the cute gimmicks! — here).

(And then, when writing this blog post, I realized that if I did a screencast, I could that then convert into something my blog accepts. Duh! So below you can watch my story the way I see it when logged into my account — including how many people watched it and all the buttons that I could click to edit and exit etc.. In the future I should probably just do the screencast from a different account to give you a cleaner view…)

By this point, it started bugging me that I was putting effort into Insta stories but that I didn’t have a good way to use them on my own blog (remember, I hadn’t come up with the screencast idea yet). I like having full control over hosting the stuff I don’t want to disappear, and I don’t like telling the same story twice for different platforms (although I realize that customizing stories for each platform and thus audience is always good advice).

So the next story didn’t use fancy gimmicks (except on the last slide), and I could export the pictures and combine them into the .gif you see below.

Mmmmh, I like that!

Except now I am thinking I should still do an English gif for my blog and keep the German one to my Instagram. Which, again, feels like a lot of work for something that I want to do in random pockets of time like on my commute, not as a real task. So my next story was a language-free one:

So in the end it turns out that classical gifs work quite well for transporting my stories. Not nearly as cute as they could be, but maybe that’s ok?

What do you think? What style of Insta story would you like to see more of?

Option A: Give me cute little gimmicks like ducks on surfboards and ladies jumping into pools!

Option B: GIFs work well and I don’t need all the cutesy gimmicks

Option C: Other. Please elaborate! :-)

Photo comics for scicomm from the central Greenland ice sheet? Yes, please!

Do you remember how I started experimenting with an app that made sketches from photos to see if reading waves might be easier from sketches than from photos? (Btw, approximately half of the answers on whether or not sketches are easier to read than pictures were along the lines of “YES!!!! DEFINITELY!!!” and the other half were like “NOOO — DON’T DO THAT TO YOUR PICTURES!!!”)

That only happened because I saw something really cool that Petra Langebroek was testing in preparation for the outreach she was planning on doing from her expedition to central Greenland, and since I thought it was so cool, I had to download an app that could do the same, and then I fell into that hole of playing with the app…

Anyway. What Petra is doing is fascinating: From her expedition to central Greenland, she reports back using the Lego figurine “EastGRIPninja” and his scientist friends to tell the story of how science is done on top of the ice sheet. For that, she takes pictures of EastGRIPninja and his friends in real locations and lets them explore, and tell stories.

For example, EastGRIPninja gets a tour of the camp:

And that’s pretty cool — it’s not too often that I get a look into one of the domes! I don’t know what I expected to see inside, but definitely not this much plywood. And probably fewer flags, too. And (spoiler alert!) would you have guessed that they have a tabletop football game in there, too?

Also super interesting: How does going to the toilet work in the middle of the Greenland ice sheet? That’s something EastGRIPninja needs to find out fairly early on, too, and again, it’s something to do with flags. So if you are curious, you should go and check it out!

Petra says that the weather is bad right now and that she doesn’t know when they’ll be able to start drilling (and thus posting interesting science content). But there are so many questions that I have that can easily be answered in bad weather, for example:

  • does EastGRIPninja get to play tablefootball and cards etc with the scientists?
  • why drill exactly where you are and not somewhere else?
  • what’s for dinner and is it something people would voluntarily eat at home when they get back?
  • who has to cook / do the dishes?
  • how many scientists are there at any one time?
  • do you work/sleep on watches like you would at sea?
  • what’s the temperature in the dome like? Cosy?

And what are your questions that EastGRIPninja could answer?

Click on the image below to read the whole story (which is being updated pretty much daily, so remember to check back to see whether your questions have been answered and what else is going on!). EastGRIPninja, Petra and their team are still there until mid July and I can’t wait to learn more about their adventures!

#DayOfTheSeafarer — #WakeWatching on Kiel fjord

I’ve been on my fair share of ships over the years, but even though I enjoy my month or two at sea every year, I cannot even begin to express the respect I have for seafarers who spend all their working life at sea. Being away from home for at least half the year, living in a small, confined space with people they did not get to choose themselves, not even having the autonomy to choose what meals to cook while at sea, all while doing hard physical work.

The seafarers I know personally do this out of their free will — their love of the ocean compensates for the sacrifices they make to be at sea. But let’s not forget that there are also many people who don’t have the luxury to choose what job they work in.

Anyway, seafarers’ work influences us all: It provides us with wave watching opportunities: The ferry you saw in the picture above left the wake you now see below.

Jokes aside: Shipping gives us access to goods that we otherwise wouldn’t have access to. It provides us with jobs, with food, with transportation. With knowledge about the world and the ocean — without the amazing work the crews on research ships do, there wouldn’t be any oceanography!

Our lives would be very different without the work that seafarers do every day, the sacrifices they make and the risks they take. On the Day of the Seafarer, maybe stop and think for a minute about what your life would look like if it wasn’t for all these men and women, doing the work they do. I, for one, am full of respect for what they are doing! And I’ll be sure to let the seafarers that I personally know know about this today! Thank you to all the crews on the research ships that I’ve sailed on, you guys and girls are amazing!

A pilot ship making waves, and what happens to the waves over time

This is the story of a pilot ship, merrily sailing along on a beautiful day, making waves.

Since it’s windy and Kiel fjord is a little choppy, the waves break and both side of the V-shaped wake with the pilot ship at its tip are visible. See the foam of the breaking waves? And in the middle of both sides of the V, visible as a lighter-colored stripe, there is the turbulent wake where the ship’s propeller has set the water into chaotic motion.

Both constituents of the wake — the V-shaped feathery waves and the turbulent wake — stay visible for quite some time after the ship has passed!

Can you spot the one side of the V approaching the shore?

A little while later, the pilot ship returns. nice bow wave (where its bow is breaking the water apart) and all. Also note the wave field inshore of the floating wave breaker — it is a lot calmer than on the outside!

But not for long. The pilot ship is making waves!

The V-shaped wave keeps spreading, one of its sides coming closer and closer to the wave breaker.

Wow, now it’s there! Can you imagine what it will do to the floating wave breaker, and what that in turn will do to the wave field inshore?

Below, you see that the V-shaped wake is now so wide that one end is reaching the edge of the wave breaker, which is already moving almost violently in the waves.

And the moving wave breaker now produces waves of its own, radiating away from the wave breaker, towards the shore.

See how those waves propagate further and further towards the shore and form a crisscross pattern with the waves that come in through the gap between wave breakers?

That was a nice wave watching break! :-)

Wave watching on Schwentine river

Surprise! I did some wave watching yesterday!

Ok, let’s start with something simple to warm you up: A duck’s wake.

And wind waves (coming in from the top right) hitting a patch of moss on the side of this little pier, and then radiating away as half circles.

Here is a movie of that because it’t pretty cool, actually.

Are you ready for the cool stuff? A water strider making waves in the movie below! It hops happily on the water, and every time it lands, capillary waves radiate outward from its point of impact.

And in the movie below, there is another water popping up after a couple of seconds. But what I find fascinating about the movie below: In the beginning, there are these smooth waves running through that were created by a breeze further upwind on the lake. But over the course of the movie, the texture of the surface changes: It gets rougher and ripples appear as the breeze moves in where I am filming. So within half a minute the lake looks substantially different!

And below a movie clip that should be used in physics classes because it illustrates so nicely that waves transport energy, not matter. How do we see that?

Can you spot the long waves going through right to left, and the small ripples that seem to, if anything, move from left to right? (Not true, that’s an optical illusion! They are moving right to left, too, only so much slower than the longer ones)

But if water was moving with the longer waves, the small waves would have to be transported with it, just riding on the other wave field. Clearly that is not the case! And that’s because only energy and the shape of the waves is transported, not the actual water the waves consist of.

And below is the picture that I would use to open my hypothetical wave photography exhibition with. Or maybe have it printed in a size to fill a whole wall if I ever had to furnish a large house.

Wave watching on Brodowinsee

What do you do the night before the most important three days of your whole work year? Yep — some wave watching with friends!

On Thursday night, we went to cool down and relax after preparing for GEO-Tag der Natur all day long. Don’t these images make you feel much more calm instantly?

And look at the waves in the atmosphere that only become visible because, as air is moved up and down by the waves, conditions change such that clouds form in the troughs but disappear at the peaks of the waves. Contemplating these things is so relaxing to me! Especially when looking at them both in the sky and in their reflection on the water.

And if you look carefully at the picture above, you see tiny little wave rings in the lower right corner. That’s small fish touching the lake’s surface from below, creating disturbances that propagate away from where the surface was deformed.

Other things make similar pattern, albeit on a larger scale. My colleagues K and K, for example, are creating wave rings, too. Theirs are much larger and propagate all the way across the lake!

And thanks to K&K’s waves, the reflections of the atmospheric waves on the water becomes even more interesting as they are deformed by surface waves on the lake.

Is there any better way to calm down any worries you might have?

And, btw, the GEO-Tag der Natur turned out a blast. I’ll update you on that once I’ve had A LOT OF SLEEP! Until then — go and do some wave watching! :-)