Are you following fascinocean_kiel on Instagram already? You definitely should!

fascinocean_kiel is my latest scicomm project — I am posting daily pictures from Kiel fjord together with a german description of some cool oceanography stuff you can see on the picture. But Instagram has a pretty good translator built in, and I am happy to translate any post if you leave me a comment with the picture you are interested in!

My latest post is the picture above: Here you can calculate the dominant wave length from the length of the pier and where waves are breaking through the floor boards of said pier. Storms are awesome when you are safely on land!

And below you can take a look at the whole fascinocean_kiel Instagram feed. See you over on Instagram? :-)

A sketch of a learning sequence on fjord circulation experiments

I’ve been wanting to develop a good fjord circulation experiment for a long time now — I wasn’t happy with the one we used back when I was teaching in Bergen, and then 1.5 years ago I talked with Steffi and Ailin who took over the tank experiments in Bergen a while back and we wanted to do something about it, but it just never happened. Life, you know, and jobs with other foci…

But then when I couldn’t sleep, I decided that 4:15 in the morning is a very good time to sketch out how I would develop a learning sequence on fjord circulation. Let’s see how I feel about it at a more normal hour after some more sleep, but right now I am happy with it, and excited to flesh out the sketch a little more with actual instructions for experiments. Would you be interested in reading that? And where would you look for instructions like that (except for on my blog)? I am hoping to maybe publish it somewhere “official”…

Awesome outreach collaboration to continue: We won a Bjerknes Visiting Fellowship 2018!

We are excited and grateful for a great opportunity for continued collaboration that has recently presented itself: Elin won a Bjerknes Visiting Fellowship 2018 for me to visit her and the rest of her team in Bergen for a month in 2018!

We have several goals for that visit, but the main one is to develop more hands-on experiments (which we lovingly call “kitchen oceanography”), which parents, teachers, and other educators can use to get children excited about oceanography (and obviously for the grown-ups to play with, too :-)). Between Elin and me, we do already have a lot of experiments which we use regularly and recommend (for Elin’s, check out this site, and mine are here). But we would love to bring them in a different format so that they are easy to find and use, and are well integrated with the ekte data project. And then, obviously, we want to let everybody in Bergen (and all of our faithful readers) know where to find the experiments, and how to use them in science communication.

So plenty of stuff to stay tuned for! We’ll absolutely keep you posted on our progress on here!

Presenting our new school lab on “energy in the climate system” at a conference

Next week we’ll be presenting out new lab on energy in the climate system (read more about it here) at a conference.

The main focus is on actually presenting and conducting the experiments and showing and discussing the materials we developed, but I put together two posters to put up in some corner, to have something to point at while giving a brief overview over the concept and the experiments.

If you are curious, here they are (unfortunately in german, but give me a shout if you would like a translation of something!).

Poster 1 is about the general concept and the three phases of the lab: The overarching question, the experimental phase, and the expert puzzle which we use together with the MSCM model (more about that here) to bring the experts to a common understanding of the system.

Poster 2 is just a bunch of pictures of individual experiments that are being done at the different stations. And I realized I urgently need better pictures for the next conference! Especially pictures with kids on them and not my team.

So here we go! That’s what I’ve been up to recently.

Dipping a toe into instagramming

This month’s private* #scicommchall: Run a scicomm Instagram feed! See the feed below. I’m doing this for several reasons: First: curiosity, how Instagram works for me personally as a scicomm format. Second: more curiosity, whether I can actually reach a german-speaking audience** that isn’t “just” scientists who are interested in the topic anyway. Third: Building my portfolio as a scicommer. Fourth: A little bit of laziness. You might have noticed my long blogging hiatus. I was sick for a long time, and now that I am back at work, I feel like I should pay a little more attention to what I spend all my time and energy on. Of course I still have to talk about water! But maybe this format is a little better suited for me at the moment. So I will definitely still write posts on this blog, but maybe not as many as you’ve gotten used to over the last years. But if you want to hear from me regularly, follow me on Instagram!

*”private” as opposed to the public #scicommchall that I have started. Since the beginning of this year, I am one of two scientific coordinators for the Kiel Science Outreach Campus (KiSOC), and I am challenging my colleagues there now, too. But I will report on that one another time…

**if you see a post you are interested in and would like to know what it says, just comment on that post and I’ll happily provide a translation! I’ve just decided against posting in two languages because I am lazy… ;-)

Cloud in a bottle experiment

Guest post by Susann Tegtmeier (written two months ago, I just never got around to posting it. Sorry!)

No one likes clouds when they bring rain, but what if you could make your own? Making a cloud inside a bottle will help us to understand how they are formed in the atmosphere. The experiment demonstrates how changes in air pressure, temperature and volume are related and how these changes can lead to the sudden appearance of tiny water droplets, or in other words, lead to the formation of a cloud.

You can do the experiment alone at home, in front of a classroom or as a hands-on experiment with all your students. I have chosen the latter option as part of my ‘Introduction to meteorology’ lecture for the first-year students in the Bachelor program ‘Physics of the Earth System’. For this class, Mirjam and I received funding from our university’s PerLe project for teaching innovations. We use the PerLe funding to consolidate the student’s physical-based understanding of the climate system through various experiments, exercises and discussions.

For the experiment you need an air-tight, transparent container that you can pump up with air (in order to increase the pressure inside the bottle). We made a simple version using materials from home including a plastic water bottle supplemented with valve from a bike tire that is attached between the bottle and the cap. Furthermore you need a pump (in our case a bike pump), water and matches.

Picture by Susann Tegtmeier

During the first round of the experiment, the students pumped up the bottles enhancing the pressure inside. During our discussion before the experiment, the students assumed correctly that the bottles would warm due to the enhanced pressure under a constant volume. By putting their hands around the bottles, it was possible for the students to feel that indeed the air inside the bottles was warming. When opening the valve slowly the opposite effect could be noticed and the bottles cooled very quickly. While the temperature change is small, it turned out to be quite fascinating and memorable for the students to see and feel the ideal gas law, they learned about earlier in class, in real life action.

During the second round of the experiment, the pumping up of the bottles was repeated, but this time with a small amount of water in the bottles. Since warm air can take up more water vapor than cold air, some of the water in the bottle was evaporated during the increase of pressure and temperature. While we discussed this effect during the experiment, it was, of course, not possible to observe the formation of the invisible water vapor. The next step of the experiment, the opening of the valve and the accompanying cooling of air, can theoretically lead to the condensation of the above discussed water vapor back to water. However, to the surprise of the students, no condensing little water droplets could be seen in the bottles.

Picture by Susann Tegtmeier

In order to lift the mystery, we carried out the third part of the experiment. With the bottle open, we lit a match and a moment later threw the blown out, smoking match into the bottle. Now the bottle needs be closed quickly before the same action (pumping of bottles and opening of valve) can be repeated. Only in this last round of the experiment, the expected water droplets became visible while the air was cooling. The reason is that small condensation nuclei are necessary for water vapor to condense and form water droplets. The experiment demonstrates this effect quite nicely in the bottle, but it also holds on large scales for the formation of atmospheric clouds.

The ‘Cloud in a bottle’ experiment is a perfect class room exercise, as it leads the students within 30 min from the basic, physical principles of the ideal gas law to one of the big climate effects, the aerosol – cloud interaction.

The mystery of Lokksund. Mysterious as ever, and I am still intrigued…

Forget climate change and all the big questions, there is this one thing that is really bugging me because I haven’t figured it out yet, but I really want to: This morning, when I was searching my old backup drives for data for my friend, I came across my favorite oceanography riddle of all times (which is still, as far as I know, unsolved!).

In 2012 and 2013, I went on cruises in the area of Hardangerfjorden, and there is one place that I find very intriguing: A narrow straight, connecting Hardangerfjorden in the south to Bjørnafjorden in the north. This straight is called Lokksund, and in its narrowest bit it’s only something like 20 meters wide and 30 meters deep. Which, as soon as water levels on both ends of the street are not exactly the same, leads to pretty strong currents.

In the description of Norwegian shipping lanes, it says about Lokksund “in the narrow part of the straight, the tidal current can be strong, up to 3-4 knots during spring tides, shifting direction every two hours. It goes southward for two hours before high tide, stops at high tide, goes north for two hours after high tide, and so on. … If there is constant wind from the south, the current can go continuously northwards. For wind from north or west, the same situation can happen with southward currents” (Den norske los 3, Farvannsbeskrivelse, Jørem Rev-Stad, 2006).

That the current is very strong in the straight was fairly obvious, and captain and crew were understandably not too happy that we wanted to spend a lot of time there (funnily enough, it’s Lokksund you see on the map on the screen in the picture below! Clearly, I really wanted to go there!).

Screen shot 2012-03-09 at 6.24.50 PM
On the bridge, discussing the scientific plan for the next day. Picture courtesy of Angus Munro.

However, the current directions that we observed didn’t seem to agree with the farvannsbeskrivelse, but they also did not seem to agree with tides from mooring data we had from north and south of the mouths of Lokksund. So we ended up doing a repeat CTD station just north of Lokksund. The CTD data is very interesting:

Above, you see a plot for salinity, and below for temperature. And there is a strong interface in both S and T — approximately at sill depth! — that is oscillating with the same frequency as described in the farvannsbeskrivelse, although from what I remember the timing was somehow different from what we expected based on the tides from the mooring data we had available.

Also, looking at how narrow the straight is, even with peak speeds of 3-4 knots, the volume of water that can actually go through Lokksund is actually very small. So even though the mixing in the narrow spots with high speeds is probably very high, the volume of displaced water is still very very low, and it’s not even clear how big its influence on mixing between the two fjords is.

But that’s not what makes me so intrigued: It should be such an easy system to understand: A narrow straight and water levels on either end driving the flow through the straight. Right? Except there is clearly more to it, and I wish I could go back there and figure out what that is!

I know for a fact that to this day, some of the crew vividly remember the time we spent in Lokksund during that cruise, and that they don’t have the fondest memories of being in a narrow straight in a strong current in the dark. But I still think it was good we spent all that time there, and luckily Elin is taking on this riddle now, hope you will keep us posted on what you find! :-)

“Laboratory layered latte” – combining latte and double diffusion. Easily my favourite paper ever!

My friends know me well. Especially A&I, which was proven again when they sent me the link to an article about two things that I am mildly obsessed with: Latte and double-diffusive mixing.

My obsession with latte is a fairly recent thing, but I have been known to blog about interesting convection pattern in it (for example here). The obsession with double-diffusive mixing, however, is well documented for more than the last 12 years (for example when I am writing experimental instructionspoems or scientific articles about it).

The double-diffusive process that I have been most concerned with is salt fingering, because it is oh-so-pretty, and also fool-proof to create for teaching purposes (when you know how to do it).

Diffusive layering I seem have to be a little frustrated with, at least in teaching (but reading back this post now, it turns out that that was entirely my own fault and not my students’. Oh well, you live and learn! Isn’t this exactly the kind of stuff that makes for great teaching portfolios? ;-)).

And it also turns out that I did the experiments themselves all wrong. According to the article “laboratory layered latte” by Xue et al. (2017) I should not have been trying to carefully stratify a tank in order to see diffusive layering. Instead, I should just have quickly poured the lower density fluid into the higher density one, and layers would have formed by themselves!

So there is one thing that you won’t see any time soon:

Yep. Me drinking latte from any kind of vessel that doesn’t let me look at the stratification! I don’t know how I could ever have fallen into the trap of missing out on observing fluid dynamics while having my early morning coffee in the office. Now I urgently need a nice glass mug!

And you should go check out the article, it’s a really nice read. My new ambition in life: Write a fluid dynamics research article that applies the FD to some really cool, yet mundane, every day thing. Are you in, Elin? :-)

Xue, Nan and Khodaparast, Sepideh and Zhu, Lailai and Nunes, Janine K. and Kim, Hyoungsoo and Stone, Howard A., Laboratory layered latte. Nature Communications 8(1), 2017

The energy lab’s dry run. Or: I have a great team! :-)

At first, I wanted to call this blog post “behind the scenes of a school lab” until I looked through the pictures and realized that all I am showing is people sitting around my desk in my office! Actually, not only sitting — test-running all the experiments for our energie:labor!

First, here is Julian’s experiment on atmospheric CO2.

And here an experiment from Jonas’ station on the role of the ocean in the climate system. A candle below an air-filled balloon. Can you imagine what will happen next?

Yes, this.

Sorry about the jump in perspective — even though I knew what would happen I clearly didn’t expect it enough to hold the camera stable. Small consolidation that everybody else clearly jumped, too?

Anyway, the point of that experiment is to look at the heat capacity of air and water. I’ve written about this before, see here (where we also have pictures of bursting the water-filled balloon because this is how we roll. But only in the lecture theatre, not in my office… ;-)).

Below, we are looking at Jonas’ overturning experiment, apparently discussing the work sheets. It’s really great how well this team works together on developing all their materials, even though their personal styles span the whole spectrum of teaching styles!

But we were also having fun, or at least that’s what it looks like… ;-)

In the picture below, taken on the second day of our dry run a couple of days later, we are looking at Henning’s station on the ice-albedo-feedback. As Henning is sitting next to me and we are sitting around my desk, he’s unfortunately not even in the picture!

In the background of the picture above you see the next exciting station that Nicolas prepared (and big shout out to my office mate who didn’t beat an eye when she came in and the office was filled with all our equipment and smelled of vinegar and white spirit…

What the guys are doing on the picture below? Using a bike pump to increase the pressure inside that bottle to make a cloud in a bottle.

Worked really well!

And then, there comes the most sophisticated piece of equipment of the whole lab: Nicolas’ cloud chamber. I’ll only tell you this much for now: It’s awesome! And you should stay tuned for an upcoming publication on how to build it and how to use it in teaching. Because it’s that great!

Now I’m out of pictures, but there is one last thing I want to say: Thank you, team, you are awesome! :-)

My new school lab on energy in the climate system has been launched! :-)

Today was a very exciting day: We launched my new school lab on energy in the climate system! The “energie:labor” is finally up and running again!

Let me walk you through some of the stuff that is going on in the lab.

Below, you see Mirko, who leads the station on the hydrological cycle, and his group working on an experiment.

In the left jar, you see how much smoke a burning piece of paper makes. The students tried this in order to compare it with the jar on the right. Because what they see in there is not just smoke from a burning piece of paper, it’s steam from the hot water at the bottom of the jar — a cloud in the jar! And the burning paper was just added to provide aerosols as condensation nuclei for the clouds.

Another part of the energy puzzle of the hydrological cycle: How much do raindrops falling down on the ground actually heat up the ground? The students are looking at the wooden board on the floor, using a thermal imaging camera. They won’t see a lot when the bouncing ball hits, but they saw a clear signal with the heavy metal ball they used earlier! Kinda like what we did at the European Researcher’s Night (see here).

Now, they are documenting their observations.

And later, they are running an experiment looking at how much moist vs dry air heats up in that insulated container below the lamp to explore the greenhouse effect of water vapour. The setup of this experiment was developed by Julian who is leading a different station on CO2 in the atmosphere, but sadly I don’t have any good pictures of that station!

On the table next to the hydrological cycle team, there is Jonas, working on the role of the ocean in the climate system. Below, the students are dunking air-filled bottles into hot and cold water baths to watch how air expands and contracts depending on its temperature.

They seem to be having fun!

Later, the team at this station did an overturning experiment. I have tons of pictures of that experiment, because it is just super photogenic (or because I am just still fascinated every time I see it, who knows?)

They are using a very strong lamp to model the heating by the sun near the equator, and cold packs to cool near the poles.

And they seemed to enjoy playing with food dye!

We have two more stations (or three, including the CO2 station I mentioned above), one on clouds run by Nicolas, and one on ice-albedo-feeback run by Henning. Unfortunately I don’t have good pictures of those, either, but I will post pictures of our trial run soon, where they’ll be featured, too.

Let’s close this by looking at how we brought all our new experts back together (because each group only conducted one station, for which they had almost all morning) — by using the Monash Simple Climate Model! I’ve written before about how great it is in teaching (see here), and I am still a big fan!

The new “experts” on clouds, the ocean, the hydrological cycle, atmospheric CO2 and ice-albedo feedbacks explained their topics to the rest of their groups. And — surprisingly enough — in the model, you can switch on and off each of these processes individually and see what effect it has on climate!

I think this worked really well to engage students in discussions about the processes they had just explored, and how they work together. Although I want to work on the kind of questions that guide them through the model before the next class visits the school lab in January…

But all in all, I am very happy with how the launch went, and I am super grateful to my great team! Thanks, Jonas, Julian, Nicolas, Mirko, and Henning (from the left in the picture above)! Hope you are enjoying your well-deserved weekend!

And last not least: Thank you, Frank, for letting us borrow your pupils! They were the nicest group we could have hoped for!