An experiment showing how seemingly straight trajectories can be transformed into curly ones. One of the phenomena that are really not intuitive to understand are fictitious forces. Especially relevant in oceanography: The Coriolis force. The most difficult step in understanding the Coriolis force is accepting that whether or not a trajectory appears straight or curved […]
Comparing a rotating and non-rotating dipole. I just realized that I never explicitly showed the difference between rotation and no rotation, even though I do have the footage to do so: Two experiments set up to create a monopole, which both turned dipole. In the non-rotating experiment (which was, by the way, set up carefully in […]
Because sometimes it’s easier to control a computer than rotation, salinity, water and dye. After looking at a non-rotating cylinder collapse the other day, it is time to look at proper hetonic explosions (you know? The experiment on the rotating tank where a denser column of water at the center of the tank is released when […]
Or: This is what happens to a hetonic explosion experiment without rotation. I’ve posted a lot while at JuniorAkademie a while back, so it is hard to believe there are still experiments from that time that I haven’t shown you. But I’ve probably only shown you about half the experiments we’ve done, and there are plenty more […]
Because sometimes one overflow simply isn’t enough. Finn’s group came up with – and ran – an overflow experiment with many different densities and even more colors. While the movie didn’t turn out too well, the idea was pretty awesome. Rolf went ahead and modeled the experiment right away. And because the plume didn’t go across […]
Water running uphill during spin-down – how much more awesome can it get? After hours, when all but the most curious students had left, Rolf and I ran another collapsing cylinder experiment, this time on Rolf’s old disk player turned rotating table. Rolf has a cone-inset for the round tank, and we set a cylinder […]
Von Carolin und Marie Am heutigen Tage wurden auch das Salz, die Dichte und die Wellen endgültig überführt. Das, was jetzt noch alles abschließt, ist die morgige Gerichtsverhandlung. Darauf haben sich alle Detektive genauestens vorbereitet und sie haben sich überlegt, wer welche Beweise im Gerichtssaal vorstellt. Genauere Details werden aber Morgen noch geklärt. Die Salzüberführung […]
My absolute favorite experiment ever: salt fingering. I know I’ve said it before about another experiment, even today, but this is my absolute favorite experiment and I still get endlessly fascinated. I’ve written about salt fingering before, and given tips on run the experiment, but today we tried a different setup. We used the same […]
Trying to tweak conditions to force a set number of vortices. We’ve done the hetonic explosion again. This time the group was super careful to calculate the Rossby radius correctly, and then to set up the experiment accordingly. We aimed for a single column like in our tilting of a frontal surface under rotation experiment. We […]
One of my all-time favorite experiments. The salt group got a bit bored from watching ice cubes melt, so I suggested they look at temperature differences for a change, and they ran the “leaking bottles” experiment. Watch a movie combining their four different setups below!
In order to not be in the eddying regime, this time we are rotating our tank as slowly as possible. Since we ran the Hadley cell experiment the other day, I’ve been obsessed with running it again, this time with the slowest rotation possible in order to visualize a different flow regime – one were […]
Von Carolin und Marie Heute haben sich die Lehrlinge gegenseitig ihre beantworteten Fragen vorgestellt. Vollständig überführt wurden zurzeit das Klima und die Strömungen, die Gezeiten und das Eis. Beim Salz und der Dichte, sowie bei den Wellen, sind noch einige wenige Fragen zu klären. Die Übrigen Lehrlinge beantworten nun einige Fragen, denen kein Täter zuzuordnen […]
A wind stress is applied to the surface to cause mixing. This is an experiment that I have been wanting to do for a long time, but somehow it never worked out before. But last night Martin and I finally ran it! We ran two experiments, one after the other. In the first one, we […]
Von Carolin (12) und Marie (13) Am heutigen Tage wurden die gesammelten Hinweise genauestens dokumentiert. Dann begannen die Lehrlinge ihren Tätern weiter auf die Schliche zu kommen. Es wurde getestet, ob der Täter Welle ein Problem mit Steinstränden hat. Der Täter Gezeiten wurde auf die Verteilung des Meeresgrundes geprüft. Den Strömungen wurde nachgewiesen, dass ihr […]
“At sea” in quotes, because technically we were at the mouth of the Weser river… But still! (deutscher Text unten) The really exciting thing working with the kids here at the JuniorAkademie is that they are really good at transferring things that we talk about theoretically to what they see in a tank experiment, and even […]
Picture dump – in german only today, sorry. So. Noch schnell die Bilder von der heutigen Ausfahrt auf der Uthörn für alle, die es gar nicht erwarten können! Hier ist das Schiff: Wir hatten natürlich ein ambitioniertes wissenschaftliches Programm. Zum Beispiel mit mehreren, vom Wind-Workshop selbstgebastelten, Anemometern die Windgeschwindigkeit messen. Zuerst mussten die natürlich an […]
Creating waves and watching them interfere. (deutscher Text unten) You might not have guessed it from reading about our waves meeting over a sandbank experiment, but we weren’t doing in purely for its entertainment value. Our goal was to see how waves interfere, because the theory of interfering waves seems to be counter-intuitive in some […]
Von Carolin (12) und Marie (13) Heute war der Tag der Tage: Die Detektive sind mit dem Forschungsschiff Uthörn zum Tatort gereist. Zuerst mussten die Lehrlinge sehr früh aufstehen und dann mit dem Bus zum Hafen fahren. Dort sind sie auf das Forschungsschiff gegangen und die Matrosen haben ihnen die Sicherheitsregeln noch einmal vor Ort […]
Creating waves in a tank. (deutscher Text unten) In the big tank, we have a paddle that is really good for making big waves. And if you create them in just the right way, they reflect at the back of the tank to meet up with the incoming waves right above the “sandbank” we put in […]
Cooling and rotation combined. (deutscher Text unten) I can’t believe I haven’t blogged about this experiment before now! Pierre and I have conducted it a number of times, but somehow the documentation never happened. So here we go today! Martin and I ran the experiment for our own entertainment (oh the peace and quiet in […]
Tomorrow, we’ll all go on a cruise! (deutscher Text unten) Tomorrow, we’ll take all 17 participants on a cruise on the Weser. So today, we talked about how that is going to be, and groups presented the instruments they are going to work with. Plankton nets, CTDs, anemometer and more. It’ll be fun! Heute haben […]
Or, an experiment on this blog often known as “slumping column”. (deutscher Text unten) If you don’t scale your tilting of frontal surfaces under rotation experiment correctly, you get a phenomenon called “hetonic explosion”: the formation of a cloud of baroclinic point vortices. From the densities, the rotation rate, the dimensions etc you can calculate the Rossby […]
Von Carolin (12) und Marie (13) Am heutigen Tage waren die Lehrlinge wieder besonders fleißig, denn sie mussten sich auf die spektakuläre Reise zum Tatort vorbereiten. Doch bevor dieses geschah, haben sie noch eifrig Indizien gesammelt. Die Gruppe, die sich mit dem Täter Eis befasste, hat die Dauer der Tat festgestellt. Der Täter Strömungen wurde […]
Plus all kinds of dyes. (deutscher Text unten) Using the continuous salinity stratification created yesterday, Rolf and Daniel conducted a really cool experiment: They forced internal waves and watched them develop. I’ve converted their movie into a time-lapse; watch it below. Mit der kontinuierlichen Salzschichtung, die Daniel und Rolf gestern gebastelt haben, haben sie danach […]
And watching internal waves – a data-model comparison. (deutscher Text unten) In an experiment similar to the one done by the group looking at the effects of temperature and salinity on density, the wave group, supported by Rolf, started looking at how to create a continuous stratification through internal wave action. Two water masses, one saline […]
Von Carolin (12) und Marie (13) Heute sind die Detektivlehrlinge schon mitten in der Planung der Experimente, aber Meisterdetektivin Glessmer erklärt vorher noch, wie sie ein Experiment vorbereiten und durchführen sollen. Die erste Gruppe, die ein Experiment durchführt, glaubt, somit die Strömungen und das Klima zu überführen. Sie planen alles nach dem Prinzip von Detektivin Glessmer und […]
Looking at wave length, frequency and speed. (deutscher Text unten) The wave group played with a tank and a hair dryer (the hair dryer safely away from the water, obviously) and different modes of recording. high definition, slow motion and what have you. They also did a really cool data-model comparison, which is still top-secret, but […]
Removing a barrier between waters of different densities and watching what happens. (deutscher Text unten) Today, one of the groups performed a classical experiment (shown for example here) – but the awesome thing is that they came up with the planning pretty much by themselves in order to determine the effects of temperature and salinity […]
A first attempt where gravity (due to a tilted axis of rotation) replaces the pull of the moon. (deutscher Text unten) The movie contains both a view from a co-rotating camera and from a non-rotating camera. Gezeiten im rotierenden Tank, in dem die Anziehung durch den Mond durch Erdanziehung simuliert wird, die wir durch eine […]
Luckily I’m not the only one believing that we absolutely need remotely controlled boats! – Zum Glück bin ich nicht die Einzige, die findet, dass wir ferngesteuerte Boote brauchen! Mein Boot hat Hochkonjunktur. D. kann es in einem Tank wenden, der nur etwa 1.5 mal so breit ist wie das Boot lang! Das kann man […]
Cooling on one end of the tank, heating on the other: A temperature-driven overturning. [deutscher Text unten] Always one of my favorite experiments – the overturning experiment (and more, and more). Unsere “Klima und Strömungen”-Gruppe hat heute ausprobiert, wie man in einem Tank eine Umwälzströmung erzeugen kann, indem man an einem Ende wärmt und am anderen […]
The most impressive hydraulic jump might be in the Denmark Strait, but there are others around, too! [deutscher Text unten] When filling the big wave tank with a hose, we can see a hydraulic jump. Of course, the flow field isn’t mainly controlled by hydraulics, but still we see the Froude number changing from greater […]
Planning and conducting a scientific study [deutscher Text unten] Before letting loose all 17 junior scientists, we talked about the scientific method, about lab safety and common pitfalls. And now they are ready to go! We estimated that developing a hypothesis and planning the experiments would take them all morning, but several groups are starting […]
Mission Ozeanographie Von Carolin (12) und Marie (13) Tag 1 Die Meisterdetektive Käse, Vogt und Glessmer wollen 17 neue Lehrlinge in 8 Tagen das Detektivleben im Hauptfall Ozean näherbringen. Kaum sind sie da, werden neue Fälle gemeldet: Der Ozean hat schon wieder sein Unwesen getrieben und einige Fragen sind noch ungeklärt. Die Detektive teilen sich in fünf […]
These are the questions we are hoping to answer during our 8 days at the JuniorAkademie [deutscher Text unten] 17 participants and 66 questions! We managed to cluster the topics into five working groups: “Climate”, “Ice”, “Currents and Tides”, “Salt and Density” and “Waves”. We learning-provokers have ideas for experiments for all of those topics, […]
More toys we brought for the JuniorAkademie For the JuniorAkademie, we brought all kinds of toys. The ones that I am most excited about is this remotely controlled boat. I am pretty sure that I wasn’t older than 8 when I got that boat, and when I discovered it the last time I moved houses, […]
Using air for reducing ship resistance and for propulsion. [deutscher Text unten] One of my favorite toys at the moment: My new hovercraft. Unfortunately, it has a couple of issues. As A and I realized in a field test: it does not like wind. And even under control conditions in a lab, it doesn’t always go […]
A week-long workshop for school kids on ocean and climate, using both tank experiments and numerical models. [deutscher Text unten] Be warned: I will post a lot over the next 8 days. And that is because I am attending the JuniorAkademie “Wind und Meer” in Bad Bederkesa in Lower Saxony, Germany. The JuniorAkademie is aimed at […]
