Category Archives: method

Asking questions that aim at specific levels of the modified Bloom’s taxonomy

I’m currently preparing a couple of workshops on higher education topics, and of course it is always important to talk about learning outcomes. I had a faint memory of having developed some materials (when still working at ZLL together with one of my all time favourite colleagues, Timo Lüth) to help instructors work with the modified Bloom’s taxonomy (Anderson & Krathwohl, 2001), and when I looked it up, I realized I had not blogged about it. But since I was surprised at how helpful I still find the materials, here we go! :-)

The idea is that instructors are often told to ask specific types of questions (usually “concept” questions), but that it is really difficult to know what that means and how to do it.

So we developed a decision tree that gives an overview over all different kinds of questions. The decision tree can support you in

  • constructing questions that provoke specific cognitive processes in your students,
  • checking what exactly you are asking your students to do when posing existing questions, and
  • modifying existing questions to better match your purpose.

The nitty gritty details and the theoretical foundation are written up in Glessmer & Lüth (2016), unfortunately in german. But check out the decision trees below, I think they work pretty well on their own! We have four different versions of that decision tree, that guide you through both the cognitive and knowledge dimension until you reach the sweet spot you wanted to reach. Have fun!

Here is one example, links to the others below.

Downloads:

  • Abstract decision tree (most helpful for getting familiar with the general concept) [pdf English | pdf German]
  • Decision tree with example questions (most helpful for constructing, or classifying, or changing questions) [pdf English | pdf German]
  • Decision tree with example multiple-choice questions (most helpful as inspiration when working with multiple-choice questions) [pdf English | pdf German]
  • Comparison of our decision tree with “conventional” types of questions (if you want to find out what a “concept question” really is when classified in the Bloom taxonomy) [pdf English | pdf German]

Any comments, feedback, suggestions? Please do get in touch!

Glessmer, M. S., & Lüth, T. (2016). Lernzieltaxonomische Klassifizierung und gezielte Gestaltung von Fragen. Zeitschrift für Hochschulentwicklung, 11 (5) doi: 10.3217/zfhe-11-05/12

“Excursion week” in Oceanography 101 while physically distancing

My friend’s university recently decided that “excursion week” (a week in May during which there are no lectures or exercises or anything happening at university to make time for field courses during the semester) is cancelled this year. Which is, of course, not surprising given the current situation, but it isn’t cancelled as in “go have a week of vacation”, it’s cancelled as in “one more week of lectures”. Which is putting even more of a burden on people who are already struggling to provide students with the best teaching they can in a new, online setting. To help my friend out (as well as anybody else who might be teaching intro to oceanography classes right now), I’ve collected a couple of ideas of how to fill this week in a way that’s keeping at least a bit of the spirit of exploration alive.

Learning about concepts, observations, experimentation

Of course I can’t give you a solution that perfectly replaces a field course by something that isn’t a fieldcourse. But that doesn’t mean that many of the learning outcomes usually associated with field courses can’t be had in non-fieldcourse settings.

What are the learning outcomes that you care about most? Understanding of specific concepts? Then maybe those concepts, even though most impressively seen at the location where you typically go for your field course, can be observed in other places, too, if students are guided to find them. Or learning to observe following a specific protocol? Then maybe this protocol can be followed (or mostly followed) while collecting a different type of data than it is usually used on. Here are a couple of suggestions of ways to do this:

A: Field course at home

There are two different scenarios that I think can work well here: Having students explore the world right outside their home with a focus on topics from their course, or having them explore the enormous amount of available datasets on the internet.

A.1: Exploring the neighbourhood

Assuming students are able to walk around outside their homes (as they currently are where I’m at), having them explore the neighbourhood. There are different kinds of tasks that could work depending on your learning outcomes:

A.1.1: Find examples of specific science concepts

The tasks can be very specific (“find examples of hydraulic jumps“, “observe tidal flows in a river by watching moored structures move“) or not so specific (“pick a topic related to our class and find a way to observe it”). I think this is a really nice task because it helps students discover how prevalent the concepts are in their daily lives, rather than being something that only exists in books and lectures and really far-away locations that field courses would go to. Careful, as you see with my wave watching, this can get addictive!

A.1.2: Explain something you know for sure they will be able to observe

If you know where your students currently are, you can also ask them to observe specific features and explain them (“Make a time series of positions of that moored structure in the tidal river and relate the positions to the tidal cycle“, or for tons of ideas in Bergen see #BergenWaveWatching on Elin’s blog). This is also a really nice task, again because it brings concepts from the lecture into students’ real lives. It’s also maybe a little easier to relate to the rest of your course since you have a better idea of what they will be observing and interpreting.

A.2: Exploring the interwebs

This is just a quick side note, but of course there are TONS of data available on the internet. From observations of salinity, temperature, pressure mounted on seals in Antarctica, to winds and waves observed from satellites. Many of them even come with interfaces ready to do easy plots. And I’ve been a big fan of the lovely people on Twitter (shoutout to @aida_alvera and @remi_wnd particularly, I always love your posts!) that post interesting features from recent satellite images. So much to discover! Trying that for myself has been on my to do list for quite a while. You’d think I would find time for it during Corona isolation, wouldn’t you?

A.3: Ask others for observations that students can work with

Kinda like what I do with #friendlywaves where people send me pictures of waves and I try to explain the physics I see (while dreaming that it’s me on that ship in Lofoten…). This would be so much fun if students took pictures of interesting features they saw (or went through their old pics) and then shared them and asked each other for ideas what might have happened there. Or if you asked people to take pictures for you, or accessed webcams (like this one, looking at Saltstraumen, the strongest tidal current!), took screenshots and analysed those. I’d totally be in!

[Edit 13.5.2020: Here is a cool example of a virtual field course that was done at UNIS, using videos of field sites and discussing them in groups]

B: Kitchen Oceanography

Of course, #KitchenOceanography is my solution to everything. Need to make a class more interesting? Bring some #KitchenOceanography to the classroom! Can’t teach in-person classes but want people to still have hands-on experiences? Let them do #KitchenOceanography at home! Feel down in isolation and need something to cheer you up? Do some #KitchenOceanography!

So here are a couple of ways to have students do #KitchenOceanography while physically distancing.

B.1: Following my 24 days of #KitchenOceanography

If you haven’t seen my 24 days of #KitchenOceanography yet, you might want to check it out. If you want to give your students a recipe for kitchen oceanography, there is probably something in there that works with your Oceanography 101 class! You could ask them to do one experiment that you find most relevant to your class, or pick one they find most interesting, or distribute all 24 experiments over all the students and have them report back.

And even though I’m so depriciatingly talking about “recipes” and structured activities, be assured that for most students things won’t end after they’ve done the experiment. There is ALWAYS something they observe that they still want to figure out, so there will be more experimentation going on than you expect!

B.2: Problem solving

This is a little more difficult to do if you and your students only communicate electronically and you can’t give them physical samples to investigate (but if you can place samples somewhere where students can easily and safely pick them up, you could for example give them salt water samples and ask them to figure out the sample’s salinity, or give them a fresh water and a salt water sample and ask them to figure out which one is which only using ice cubes). But there are still tons of ways problem solving can be practiced, for example by asking students to figure out ways to measure temperature, salinity and density.

B.3: Open-ended investigation

This is the most fun way to do kitchen oceanography, but depending on whether students have ever done these kinds of experiments before or not, it might be worth starting with a more guided kitchen oceanography experiment. But ultimately, this is where you ask students to figure things out in their kitchens. Currently on the list of things I want to try when I get the time (again, how is Corona isolation not the time for this kind of stuff? But somehow it isn’t): Can I actually see a change in the refraction of a spoon in a glass of very cold salt water as compared to warm fresh water? How big is that density effect? Would I be able to see the spoon bend where it goes through a density stratification in my glass? I bet you, once I start playing with this, that’s that for that evening!

C: Bonus idea: Ocean podcasts & books

There are two oceanography-themed podcasts that I really enjoy listening to (and I’m not a podcast person!): Climate Scientists and Treibholz. Both would be great to listen to interviews with super cool scientists while dreaming yourself away to expeditions to the Arctic or Antarctica. There is so much to learn from other people’s experiences in the field — why not ask students to listen to other people’s experiences with a focus on either the science, or the methods, or anything else?

And of course there are tons of books that would lend themselves to that, too, for example xplorer’s diaries. Nansen’s “Farthest North” (1897) for example fits super well if you wanted to talk about the discovery of dead water

Bringing it all together

The big question is: Once your students have done the tasks of finding/producing and describing phenomena, what do they do with that? It might not come as a surprise, but I think that they should be encouraged to publicly share them on the internet. Both because it’s a good opportunity for them to build their scicomm profile, but also because there are surpisingly many people who get really excited about (read here how Prof. Tessa M Hill‘s student Robert Dellinger posted a video of an overturning circulation on his 70-ish follower Twitter account, and the video has, as of  April 16th, 70 retweets and 309 likes!) and that’s such a motivating feedback for them!

Of course, the sharing and excited reactions could also happen within your university’s learning management system, but honestly … no. Ask them to share it via social media! I, for one, am definitely more than happy to comment and ask questions and share my excitement there! :-)

New #WaveWatching series happening over on Elin’s blog: #BergenWaveWatching!

Kjersti, Steffi, Elin and I recently discussed ways to better integrate the GEOF105 student cruise into the course. Right now,  even though students write a report about their work on the student cruise, it’s pretty much a one-off event with little connection to what happens before and after, which is a pity. Having a whole research ship for a whole day for a group of 6-8 students (or possibly 10 next year) is such an amazing opportunity! We want to help students make the most of it by attempting to foster a curious mindset before they board the ship.

One idea is to ask the students to observe things throughout the whole duration of the semester, and then have them relate their own “time series” of those observations with what they observe on the student cruise. Ideally, students will be observing their chosen topic for a couple of weeks before the cruise, then go on the cruise looking at everything there with a focus on that topic, and then continue to observe it in their daily lives after the cruise. But even if it’s not connected to the student cruise or this specific class, I think giving students the task to make regular observations over the course of a whole semester would be a really good way to connect their studies better with their regular lives outside of university.

Do I have ideas of what the topics could be? Of course! And I have scheduled posts over the next two months, in which my ideas will be presented one by one. But today, I want to talk about what I think what purpose this assignment would serve.

The goal is not to collect data that will advance science or to work on original research questions. It is rather to help students get into the practice of focussing on details in the world around them that might otherwise go unnoticed. To collect observations using only minimal resources (like for example stopping on their commute for seconds only, taking pictures with their smartphones, using the readily available weather forecast for context). To try and explain pattern they observe using their theoretical background from university. I want to help students get into the habit of actively observing what is going on around them, to become fascinated with discovering things related to their studies in their everyday lives.

I myself, for example, am absolutely fascinated with waves, and I notice them anywhere (read more about that on my blog, if you are interested). On the most recent GEOF105 student cruise, there was a bucket that was used to bring seawater up on the deck for salinity to be measured. And what jumped out on me? The standing waves in that bucket! You see them in the picture below, but what struck me was that most people really didn’t seem to notice what was going on there, and how FASCINATING it was. Someone even commented to the effect that they would have never noticed the waves in the bucket if I hadn’t pointed them out to them, even though they were sticking probes right into the waves. And while I spent the better part of two days moving the bucket around to see all the different wave pattern that occurred on different spots on deck, most other people didn’t even seem curious to find out why myself and a handful of other people were staring into a blue plastic bucket. And that makes me sad. Does everybody need to find waves fascinating? Of course not. But should students at least be a little curious about science topics that clearly fascinate their instructors? Yes, I believe so.

More about the cool waves in the blue bucket in this blog post!

So my mission with this series of blog posts is to give examples of where you can easily observe oceanography-related phenomena in and around Bergen, hoping that you might start looking at those spots with different eyes. And maybe you will find a specific topic that you become fascinated with. Because once you start focussing on something that seems random and rare, the very thing seems to appear everywhere in your daily life. Like for example hydraulic jumps. As shown in the picture below — once you start focussing on those, you see them appear everywhere as if out of thin air.

Hydraulic jumps. Picture from this blog post

This kind of curiosity around physics phenomena is — in my opinion — absolutely desirable, especially in students. It makes dry theory or seemingly obscure topics become more relevant. As you start noticing phenomena, you also start noticing more about them, for example understanding the conditions under which the appear. And you also start anticipating where they might occur, so you will look to see whether your prediction is correct. It’s a vicious circle, but one that I would encourage you — and especially students — to enter. To me, it’s part of my identity as a scientist — to use my initial understanding of processes to continuously want to learn more and more about them.

Wave watching has definitely become a part of my life that I don’t want to miss. What will you start seeing everywhere? Or what is it that you are maybe already seeing everywhere that most people don’t? I am anticipating that my suggestions in this #BergenWaveWatching series will be strongly biased towards #wavewatching, so if you have any other suggestions (maybe even with pictures already?), I would love to hear about them! :-)

…and check out the #BergenWaveWatching series here!

Guest posts, take-overs, interviews, and why I love them

Guest posts, take-overs and interviews are a great alternative to maintaining social media channels for every scientist / project / institution individually, if that isn’t what you want to be doing (or — as in my case — a great addition)

As I am preparing a workshop on online science communication, I have been thinking about how maintaining a quality social media presence requires high levels of dedication and commitment, as it requires a lot of work and time. And sometimes, for whatever reasons, committing that sort of time to online scicomm just can’t be the priority, and that is ok. So what do I want to recommend to people who are interested in principle, but who have concerns that it will be too expensive to maintain in the long run in terms of time or energy or ideas or motivation, or whatever else the limiting factor might be?

I think there are ways to do cool and impact-ful online scicomm without building and maintaining a personal social media presence (or focussing on one specific channel and audience and not feeling bad about not doing all the things that one could possibly do).

But first, I believe it is super important to get clear on why we want to appear on social media in the first place.

What are your objectives?

Being clear about what you are trying to achieve is always really good advice, for science communication on social media, outside of social media, for life in general. But especially if we are trying to minimize effort and maximise effects of online scicomm, it helps to be really clear about what the goal is.

If you want to build a community or regularly update a group of people on your project’s progress, having your own social media channels might be the way to go. And I am in no way trying to dissuade you from having your own social media channels! All my suggestions below also apply if you do this in addition to maintaining a regular presence on social media.

If you wanted to, for example,

  • convey a message without necessarily becoming visible as a person
  • create short-term visibility for a specific project / result / event
  • be highlighted to a specific audience that isn’t one you regularly (want to) engage with
  • brush up your CV on the online scicomm side (without too much regular work)
  • prepare content occasionally, but not regularly
  • dip your toes into doing scicomm in a specific format to see how it works for you,

below are some options worth considering.

Who is your audience?

Depending on your goals, you might want to address audiences as specific as, for example,

  • students at a specific university
  • young adults living in a specific country (or reading in a specific language)
  • PhD students working on polar sciences.

And you might want to reach all of them at different points in time, for different reasons and with different messages. For each audience you might want to reach, there are likely accounts already targeting that exact same group of people. The clearer you are about who your audience is, the easier it is to find accounts that have build already that audience to collaborate with.

What is your message?

And does conveying your message include interaction with your audience?

Once you are clear on all this, here are a couple of options worth considering.

Take-overs of rotating accounts

For many communities, rotating accounts on Twitter and Instagram exist. Those are accounts that are focussed on specific topics but are run by different people each week. The benefit of taking over those accounts is that there is a large established audience interested in your kind of content already, that you are instantly exposed to once you take over the account.

Take-overs typically require you to commit to posting on the channel a couple of times throughout the course of a week, and, depending on the size of the channel, it can be quite scary especially if you don’t have a lot of experience using social media beforehand. And, since those channels typically have quite a large following, you should not underestimate the time it will take to prepare content, overthink it, post it, agonize over it and regularly check how it is being received, and respond to people’s comments. But my experience with doing this has been very positive indeed.

For example, last year I took over @GeoSciTweeps (an account with, at that time, 4.6k followers, where each week a different person working in gesosciences presents what they do) and @IAmScicomm (where people working in/on/with science communication present themselves) with then 18.6k followers. Both weeks were great experiences that led to me making super interesting new connections and friendships. Depending on which community you want to interact with during your take-over week, there are many many more rotating accounts and it is definitely worth taking a moment to figure out which is the right account for your purposes.

My plan for my takeover of @IAmScicomm in October 2018

Similar accounts also exist on Instagram, for example @nordicpolarscience, which we used earlier this year to inform an audience of mainly students in anything related to nordic polar sciences about our fjord oceanography student cruise. See example below:

One of our guest posts on @nordicpolarscience on Instagram

Guest “take overs” for institutions

Instead of doing a take over on a rotating account, you could also do one for an institution like your university. I was asked to take over Kiel university’s Instagram @kieluni for a couple of days, and it was fun!

Caution — “take over” for an institution might mean something different than for rotating accounts. In case of Kiel uni it means you have to pre-produce content, and they will post it themselves. Which is actually very convenient (if you realize this early enough, which I did not. But you live and learn ;-)).

Instagram profile of Kiel University. The three posts visible at the bottom are mine!

This take over had unexpected effects: Before our first session using 4 rotating tables simultaneously, one of the students approached and asked me if it was me who did this takeover with the cool tank experiments on @kieluni weeks ago! Glad to prove to Torge, who was part of that conversation, that Social. Media. Works! :-)

Guest posts

Sometimes there are blogs that cater to your intended audience that are happy to accept guest posts.

A while back, I wrote a guest post at Sci/Why, a blog for Canadian science writers for kids. They invited me to write the guest post, and why not? It was fun!

Screenshot of the Sci/Why website

A really good example for a very successful guest posts is one I recently hosted on my blog: Dan’s post on an analogue activity to understand how machine learning works. This post received a lot of attention on Twitter and I am excited to provide my platform to give visibility to such a great project! If you are interested in writing about anything related to “Adventures in Oceanography and Teaching”, please get in touch and I am happy to host a guest post!

Another example of a guest post I did is on my friend Alice’s blog and Instagram for her #experimentalfridays series.

Guest post on Alice’s Instagram @scied_alice

What makes guest posts really convenient is that you can write them whenever it suits you, edit them as often as you might like, talk to your host about how to make them the best fit for their audience, etc.. So in a way it might feel like it is the “safest” way to do online scicomm, because it’s the slowest, most familiar way.

Being featured on accounts

There are also a lot of accounts that are happy to feature you and/or your work because their goal is community building.

For example, I was recently featured on @WeAreCAU on Instagram. Their goal is to feature people with a connection to Christian Albrechts University Kiel (CAU — hence “We are CAU”), and as an alumna I thought this was a great opportunity to connect with people at this university.

Me being featured on @WeAreCAU on Instagram

Being featured this way was also a super easy thing to do, all that was needed was a picture of myself and a short text, which I wrote when it suited me, and which they then posted when it worked with their schedule.

Providing information to other accounts

Sometimes, the goal is just to get a message out there without necessarily becoming visible as the person / project / institution behind the message. I recently met the person behind @doktorwissenschaft, a very popular german Instagram account, “Dr. Science”, who posts two science facts every day. He was happy to receive a list of ocean facts (complete with references ;-)). And using his account with 38k followers (and 3k “likes” on my most recent post on his profile) gives my content so much more visibility than I could achieve with my own channels, so I am really happy about this collaboration. Win win!

The popular Instagram-profile “Doktor Wissenschaft” posts twice daily facts in physics, chemistry and biology!

One of the ocean facts I provided to Doktor Wissenschaft

Again, this is a super easy collaboration, as both parties can work on their own schedule.

Giving interviews

This might actually be the most conventional way of reaching new audiences. And in a way it might also be the easiest way, because you are interacting with a host that will help you tailor your message to their audience, that they know a lot better than you do.

I’ve done this several times over the last year, for example on Susanne Geu’s blog, and on Ronja & Maxie’s podcast “Treibholz”.

My experience doing these guest posts, take overs, etc.

Time commitment

Depending on the kind of collaboration you choose, you need to be aware of how much work it will bring with it. I did the two twitter takeovers mentioned above while being a visiting scientist in Bergen, thinking that then at least I would have something to talk about. But trying to work on other things at the same time and going on student cruises, and that was actually a little overwhelming. Maybe also because it was the first time I tried doing something like this, but I would definitely recommend doing such takeovers on a slow week at home rather than a week where you want to make the most of visiting a place, chatting with people you don’t get to see regularly, go on cruises, etc.. Also do it during a week / in a place where you know you will have good internet access. So being on a ship might not be ideal.

On the other hand, if you choose to work with pre-produced content on channels that you will not be administering yourself when your content is being posted, this is something that you can prepare over as much time as you like and thus fit it around your schedule. So this might actually be something worth considering for a really busy and important week, on a field trip, a conference, whatever, the week your big event is taking place, to raise awareness for whatever you are up to that week without actually having to do anything about it during those busy times, and without depending on having good internet access. Provided everything is prepared beforehand…

Would I do it again?

Yes!!! As I was writing this post, more and more examples of where I have contributed to other people’s online scicomm came to my mind. I didn’t realize I had been doing it so much. And it was fun, I enjoy looking back at each individual interaction and all the different products that came out. It was also work. Of course, being suddenly able to reach audiences that I wasn’t familiar with and some that were so much larger than my usual audience was also both exciting and terrifying. I would totally do it again and I would totally recommend trying it!

And also if you are thinking about taking up a new-to-you form of scicomm, doing a guest appearance somewhere is a great way to test the waters. The coolest scicomm idea doesn’t actually carry very far if it turns out that you HATE the app you need to work with in order to communicate on a specific social media channel, you really can’t find a lot to say on a specific topic, or you find it annoying to write for a specific kind of audience. So this is a really great way to see what it would be like to do this kind of scicomm and get some reactions!

If one rotating table is awesome, four rotating tables are…?

I’m actually at a loss for words. Amazing? Spectacular? So much fun? All of that!

Today was the first time Torge and I tried our four DIYnamics-inspired rotating tables in teaching. (Remember? We want to use 4 rotating tables simultaneously so students can work in small groups rather than watching us present experiments, and also so we could quickly see how slightly different conditions might lead to different results. Having 4 tanks running at the same time cuts down on a lot of spin-up wait time! And we wanted affordable rotating tables so a) we could afford them and b) students would really just be able to play without them, or us, being afraid that they might break something). And it went even better than we had hoped, and we were already pretty convinced that it would be awesome!

It all started out, even before class started, with one of the students asking if it was me who had done the recent takeover of Kiel University’s Instagram account with the awesome tank experiments in Bergen. Yep, that was me, and it was great that she remembered she had seen the experiments and even recognized me! Made me very happy. If I had needed convincing that social media is awesome, here it was!

But then the students started playing, and they got really into it. We started out with just tanks filled with water on the Lazy Susans, and the students moved them by hand to get a feel for how water behaves under rotation. We looked at deformation of surfaces, how confetti as tracers behaved on the surface and on the bottom, all the good stuff. Already with such simple experiments there is so much physics to discuss!

And then we moved on to turbulence in a non-rotating and rotating system. Look at the cool vortex rings you can make with food coloring :-)

And then we moved on to turbulence in the rotating system. Our final tanks haven’t arrived yet, so we made do with whatever we had at hand (see the green bowl as tank below…). Students also started improvising to include a topography and other modifications that we hadn’t planned for. This is so great if students are so keen to figure things out that they take the initiative to make it happen themselves!

Judging from what I could observe, students were really enjoying themselves and got into deep discussions, trying to connect their observations to the theory they had learned. Additionally, there were lots of “oh wow!”s and “coooool”s everywhere. And I overheard this one exchange between two students: “careful, don’t drop the phone into the tank!” “oh, it’s ok, it’s waterproof” “I don’t care about the phone, I don’t want you to mess up the experiment!” :-D

Btw, note below the small Lego motor that drives the Lazy Susan. That’s really the whole setup. Speaking of affordable and easy. And portable. And all-around awesome!

And it was great fun for Torge and me, too, to observe what the students were up to, and to discuss with them. There were already several curious questions as to what experiments we are planning to do throughout the course. The next sessions, Torge will connect the experiments we did today to theory, and start on the theory we need for the next set of experiments we are planning to run, but I can’t wait to continue working with the tank experiments with such a motivated group of students! :-)

Supporting conceptual understanding of the Coriolis force through laboratory experiments

My friend Pierré and I started working on this article when both of us were still working at the Geophysical Institute in Bergen. It took forever to get published, mainly because both of us had moved on to different jobs with other foci, so maybe it’s not a big deal that it took me over a year to blog it? Anyway, I still think it is very important to introduce any kind of rotating experiments by first making sure people don’t harbour misconceptions about the Coriolis effect, and this is the best way we came up with to do so. But I am happy to hear any suggestions you might have on how to improve it :-)

Supporting Conceptual Understanding of the Coriolis Force Through Laboratory Experiments

By Dr. Mirjam S. Glessmer and Pierré D. de Wet

Published in Current: The Journal of Marine Education, Volume 31, No 2, Winter 2018

Do intriguing phenomena sometimes capture your attention to the extent that you haveto figure out why they work differently than you expected? What if you could get your students hooked on your topic in a similar way?

Wanting to comprehend a central phenomenon is how learning works best, whether you are a student in a laboratory course or a researcher going through the scientific process. However, this is not how introductory classes are commonly taught. At university, explanations are often presented or developed quickly with a focus on mathematical derivations and manipulations of equations. Room is seldom given to move from isolated knowledge to understanding where this knowledge fits in the bigger picture formed of prior knowledge and experiences. Therefore, after attending lectures and even laboratories, students are frequently able to give standard explanations and manipulate equations to solve problems, but lack conceptual understanding (Kirschner & Meester, 1988): Students might be able to answer questions on the laws of reflection, yet not understand how a mirror works, i.e. why it swaps left-right but not upside-down (Bertamini et al., 2003).

Laboratory courses are well suited to address and mitigate this disconnect between theoretical knowledge and practical application. However, to meet this goal, they need to be designed to focus specifically on conceptual understanding rather than other, equally important, learning outcomes, like scientific observation as a skill or arguing from evidence (NGSS, 2013), calculations of error propagations, application of specific techniques, or verifying existing knowledge, i.e. illustrating the lecture (Kirschner & Meester, 1988).

Based on experience and empirical evidence, students have difficulties with the concept of frames of reference, and especially with fictitious forces that are the result of using a different frame of reference. We here present how a standard experiment on the Coriolis force can support conceptual understanding, and discuss the function of employing individual design elements to maximize conceptual understanding.

HOW STUDENTS LEARN FROM LABORATORY EXPERIMENTS

In introductory-level college courses in most STEM disciplines, especially in physics-based ones like oceanography or meteorology and all marine sciences, laboratory courses featuring demonstrations and hands-on experiments are traditionally part of the curriculum.

Laboratory courses can serve many different and valuable learning outcomes: learning about the scientific process or understanding the nature of science, practicing experimental skills like observation, communicating about scientific content and arguing from evidence, and changing attitudes (e.g. Feisel & Rosa, 2005; NGSS, 2013; Kirschner & Meester, 1988; White, 1996). One learning outcome is often desired, yet for many years it is known that it is seldomly achieved: increasing conceptual understanding (Kirschner & Meester, 1988, Milner-Bolotin et al., 2007). Under general dispute is whether students actually learn from watching demonstrations and conducting lab experiments, and how learning can be best supported (Kirschner & Meester, 1988; Hart et al., 2000).

There are many reasons why students fail to learn from demonstrations (Roth et al., 1997). For example, in many cases separating the signal to be observed from the inevitably measured noise can be difficult, and inference from other demonstrations might hinder interpretation of a specific experiment. Sometimes students even “remember” witnessing outcomes of experiments that were not there (Milner-Bolotin et al., 2007). Even if students’ and instructors’ observations were the same, this does not guarantee congruent conceptual understanding and conceptual dissimilarity may persist unless specifically addressed. However, helping students overcome deeply rooted notions is not simply a matter of telling them which mistakes to avoid. Often, students are unaware of the discrepancy between the instructors’ words and their own thoughts, and hear statements by the instructor as confirmation of their own thoughts, even though they might in fact be conflicting (Milner-Bolotin et al., 2007).

Prior knowledge can sometimes stand in the way of understanding new scientific information when the framework in which the prior knowledge is organized does not seem to organically integrate the new knowledge (Vosniadou, 2013).The goal is, however, to integrate new knowledge with pre-existing conceptions, not build parallel structures that are activated in context of this class but dormant or inaccessible otherwise. Instruction is more successful when in addition to having students observe an experiment, they are also asked to predict the outcome before the experiment, and discuss their observations afterwards (Crouch et al., 2004). Similarly, Muller et al. (2007) find that even learning from watching science videos is improved if those videos present and discuss common misconceptions, rather than just presenting the material textbook-style. Dissatisfaction with existing conceptions and the awareness of a lack of an answer to a posed question are necessary for students to make major changes in their concepts (Kornell, 2009, Piaget, 1985; Posner et al., 1982). When instruction does not provide explanations that answer students’ problems of understanding the scientific point of view from the students’ perspective, it can lead to fragmentation and the formation of synthetic models (Vosniadou, 2013).

One operationalization of a teaching approach to support conceptual change is the elicit-confront-resolve approach (McDermott, 1991), which consists of three steps: Eliciting a lingering misconception by asking students to predict an experiment’s outcome and to explain their reasons for the prediction, confronting students with an unexpected observation which is conflicting with their prediction, and finally resolving the matter by having students come to a correct explanation of their observation.

HOW STUDENTS TRADITIONALLY LEARN ABOUT THE CORIOLIS FORCE

The Coriolis force is essential in explaining formation and behavior of ocean currents and weather systems we observe on Earth. It thus forms an important part of any instruction on oceanography, meteorology or climate sciences. When describing objects moving on the rotating Earth, the most commonly used frame of reference would be fixed on the Earth, so that the motion of the object is described relative to the rotating Earth. The moving object seems to be under the influence of a deflecting force – the Coriolis force – when viewed from the co-rotating reference frame. Even though the movement of an object is independent of the frame of reference (the set of coordinate axes relative to which the position and movement of an object is described is arbitrary and usually made such as to simplify the descriptive equations of the object), this is not immediately apparent.

Temporal and spatial frames of reference have been described as thresholds to student understanding (Baillie et al., 2012, James, 1966; Steinberg et al., 1990). Ever since its first mathematical description in 1835 (Coriolis, 1835), this concept is most often taught as a matter of coordinate transformation, rather than focusing on its physical relevance (Persson, 1998). Most contemporary introductory books on oceanography present the Coriolis force in that form (cf. e.g. Cushman-Roisin, 1994; Gill, 1982; Pinet, 2009; Pond and Pickard, 1983; Talley et al., 2001; Tomczak and Godfrey, 2003; Trujillo and Thurman, 2013). The Coriolis force is therefore often perceived as “a ‘mysterious’ force resulting from a series of ‘formal manipulations’” (Persson, 2010). Its unintuitive and seemingly un-physical character makes it difficult to integrate into existing knowledge and understanding, and “even for those with considerable sophistication in physical concepts, one’s first introduction to the consequences of the Coriolis force often produces something analogous to intellectual trauma” (Knauss, 1978).

In many courses, helping students gain a deeper understanding of rotating systems and especially the Coriolis force, is approached by presenting demonstrations, typically of a ball being thrown on a merry-go-round, showing the movement simultaneously from a rotating and a non-rotating frame (Urbano & Houghton, 2006), either in the form of movies or simulations, or in the lab as demonstration, or as a hands-on experiment[i]. After conventional instruction that exposed students to discussions and simulations, students are able to do calculations related to the Coriolis force.

Nevertheless, when confronted with a real-life situation where they themselves are not part of the rotating system, students show difficulty in anticipating the movement of an object on a rotating body. In a traditional Coriolis experiment (Figure1), for example, a student launches a marble from a ramp on a rotating table (Figure 2A, B) and the motion of the marble is observed from two vantage points: where they are standing in the room, i.e. outside of the rotating system of the table; and on a screen that displays the table, as captured by a co-rotating camera mounted above it. When asked, before that experiment, what path the marble on the rotating surface will take, students report that they anticipate observing a deflection, its radius depending on the rotation’s direction and rate. After having observed the experiment, students report that they saw what they expected to see even though it never happened. Contextually triggered, knowledge elements are invalidly applied to seemingly similar circumstances and lead to incorrect conclusions (DiSessa & Sherin, 1988; Newcomer, 2010). This synthetic model of always expecting to see a deflection of an object moving on a rotating body, no matter which system of reference it is observed from, needs to be modified for students to productively work with the concept of the Coriolis force.

Figure 1: Details of the Coriolis experiment

Figure 1: Details of the Coriolis experiment

Despite these difficulties in interpreting the observations and understanding the underlying concepts, rotating tables recently experienced a rise in popularity in undergraduate oceanography instruction (Mackin et al., 2012) as well as outreach to illustrate features of the oceanic and atmospheric circulation(see for example Marshall and Plumb, 2007). This makes it even more important to consider what students are intended to learn from such demonstrations or experiments, and how these learning outcomes can be achieved.

Figure 2A: View of the rotating table including the video camera on the scaffolding above the table. B: Sketch of the rotating table, the mounted (co-rotating) camera, and the marble on the table. C: Student tracing the curved trajectory of the marble on a transparency. On the screen, the experiment is shown as captured by the co-rotating camera, hence in the rotating frame of reference. 

Figure 2A: View of the rotating table including the video camera on the scaffolding above the table. B: Sketch of the rotating table, the mounted (co-rotating) camera, and the marble on the table. C: Student tracing the curved trajectory of the marble on a transparency. On the screen, the experiment is shown as captured by the co-rotating camera, hence in the rotating frame of reference.

A RE-DESIGNED HANDS-ON INTRODUCTION TO THE CORIOLIS FORCE

The traditional Coriolis experiment, featuring a body on a rotating table[ii], observed both from within and from outside the rotating system, can be easily modified to support conceptual understanding.

When students of oceanography are asked to do a “dry” experiment (in contrast to a “wet” one with water in a tank on the rotating table) on the Coriolis force, at first, this does not seem like a particularly interesting phenomenon to students because they believe they know all about it from the lecture already. The experiment quickly becomes intriguing when a cognitive dissonance arises and students’ expectations do not match their observations. We use an elicit-confront-resolve approach to help students observe and understand the seemingly conflicting observations made from inside versus outside of the rotating system (Figure 3). To aid in making sense of their observations in a way that leads to conceptual understanding the three steps elicit, confront, and resolve are described in detail below.

Figure 3: Positions of the ramp and the marble as observed from above in the non-rotating (top) and rotating (bottom) case. Time progresses from left to right. In the top plots, the positions are shown in inert space. From left to right, the current positions of the ramp and marble are added with gradually darkening colors. In the bottom plots, the ramp stays in the same position relative to the co-rotating observer, but the marble moves and the current position is always displayed with the darkest color.

Figure 3: Positions of the ramp and the marble as observed from above in the non-rotating (top) and rotating (bottom) case. Time progresses from left to right. In the top plots, the positions are shown in inert space. From left to right, the current positions of the ramp and marble are added with gradually darkening colors. In the bottom plots, the ramp stays in the same position relative to the co-rotating observer, but the marble moves and the current position is always displayed with the darkest color.

2. What do you think will happen? Eliciting a (possibly) lingering misconception

Students have been taught in introductory lectures that any moving object in a counter-clockwise rotating system (i.e. in the Northern Hemisphere) will be deflected to the right. They are also aware that the extent to which the object is deflected depends on its velocity and the rotational speed of the reference frame. In our experience, due to this prior schooling, students expect to see a Coriolis deflection even when they observe a rotating system “from the outside”. When the conventional experiment is run without going through the additional steps described here, students often report having observed the (non-existent) deflection.

By activating this prior knowledge and discussing what students anticipate observing under different conditions before the actual experiment is conducted, the students’ insights are put to the test. This step is important since the goal is to integrate new knowledge with pre-existing conceptions, not build parallel structures that are activated in context of this class but dormant or inaccessible otherwise. Sketching different scenarios (Fan, 2015; Ainsworth et al., 2011) and trying to answer questions before observing experiments support the learning process since students are usually unaware of their premises and assumptions (Crouch et al., 2004). Those need to be explicated and documented (even just by saying them out loud) before they can be tested, and either be built on, or, if necessary, overcome. 

We therefore ask students to observe and describe the path of a marble being radially launched from the perimeter of the circular, non-rotating table by a student standing at a marked position next to the table, the “launch position”. The marble is observed rolling towards and over the center point of the table, dropping off the table diametrically opposite from the position from which it was launched. So far nothing surprising. A second student – the catcher– is asked to stand at the position where the marble dropped off the table’s edge so as to catch the marble in the non-rotating case. The position is also marked on the floor with tape to document the observation.

Next, the experimental conditions of this thought experiment (Winter, 2015) are varied to reflect on how the result depends on them. The students are asked to predict the behavior of the marble once the table is put into slow rotation. At this point, students typically enquire about the direction of rotation and, when assured that “Northern Hemisphere” counter-clockwise rotation is being applied, their default prediction is that the marble will be deflected to the right. When asked whether the catcher should alter their position, the students commonly answer that the catcher should move some arbitrary angle, but typically less than 90 degrees, clockwise around the table.  The question of the influence of an increase in the rotational rate of the table on the catcher’s placement is now posed. “Still further clockwise”, is the usual answer. This then leads to the instructor’s asking whether a rotational speed exists at which the student launching the marble, will also be able to catch it themselves. Usually the students confirm that such a situation is indeed possible.

2. Did you observe what you expected to see? Confronting the misconception

After “eliciting” student conceptions, the “confront” step serves to show the students the discrepancy between what they expect to see, and what they actually observe. Starting with the simple, non-rotating case, the marble is launched again and the nominated catcher, positioned diametrically across from the launch position, seizes the marble as it falls off the table’s surface right in front of them. As theoretically discussed beforehand, the table is then put into rotation at incrementally increasing rates, with the marble being launched from the same position for each of the different rotational speeds.  It becomes clear that the catcher can – without any adjustments to their position – remain standing diametrically opposite to the student launching the marble – the point where the marble drops to the floor. Hence students realize that the movement of the marble relative to the non-rotating laboratory is unaffected by the table’s rotation rate.

This observation appears counterintuitive, since the camera, rotating with the system, shows the curved trajectories the students had expected; segments of circles with decreasing radii as the rotation rate increases. Furthermore, to add to the confusion, when observed from their positions around the rotating table, the path of the marble on the rotating table appears to show a deflection, too.  This is due to the observer’s eye being fooled by focusing on features of the table, e.g. marks on the table’s surface or the bars of the camera scaffold, relative to which the marble does, indeed, follow a curved trajectory. To overcome this optical illusion, the instructor may ask the students to crouch, diametrically across from the launcher, so that their line of sight is aligned with the table’s surface, i.e. at a zero-zenith angle of observation. From this vantage point, the marble is observed to indeed be moving in a straight line towards the observer, irrespective of the rotation rate of the table. Observing from different perspectives and with focus on different aspects (Is the marble coming directly towards me? Does it fall on the same spot as before? Did I need to alter my position in the room at all?) helps students gain confidence in their observations.

To solidify the concept, the table may again be set into rotation. The launcher and the catcher are now asked to pass the marble to one another by throwing it across the table without it physically making contact with the table’s surface. As expected, the marble moves in a straight line between the launcher and the catcher, whom are both observing from an inert frame of reference. However, when viewing the playback of the co-rotating camera, which represents the view from the rotating frame of reference, the trajectory is observed as curved[iii].

3. Do you understand what is going on? Resolving the misconception

Misconceptions that were brought to light during the “elicit” step, and whose discrepancy with observations was made clear during the “confront” step, are finally resolved in this step. While this sounds very easy, in practice it is anything but. For learning to take place, the instructor needs to aid students in reflecting upon and reassessing previous knowledge by pointing out and dispelling any remaining implicit assumptions, making it clear that the discrepant trajectories are undoubtedly the product of viewing the motion from different frames of reference. Despite the students’ observations and their participation in the experiment this does not happen instantaneously. Oftentimes further, detailed discussion is required. Frequently students have to re-run the experiment themselves in different roles (i.e. as launcheras well as catcher) and explicitly state what they are noticing before they trust their observations.

For this experiment to benefit the learning outcomes of the course, which go beyond understanding of a marble on a rotating table and deal with ocean and atmosphere dynamics, knowledge needs to be integrated into previous knowledge structures and transferred to other situations. This could happen by discussion of questions like, for example: How could the experiment be modified such that a straight trajectory is observed on the screen? What would we expect to observe if we added a round tank filled with water and paper bits floating on it to the table and started rotating it? How are our observations of these systems relevant and transferable to the real world? What are the boundaries of the experiment?

IS IT WORTH THE EXTRA EFFORT? DISCUSSION

We taught an undergraduate laboratory course which included this experiment for several years. In the first year, we realized that the conventional approach was not effective. In the second year, we tried different instructional approaches and settled on the one presented here. We administered identical work sheets before and after the experiment. These work sheets were developed as instructional materials to ensure that every student individually went through the elicit-confront-resolve process. Answers on those worksheets show that all our students did indeed expect to see a deflection despite observing from an inert frame of reference: Students were instructed to consider both a stationary table and a table rotating at two different rates.  They were then asked to, for each of the scenarios, mark with an X the location where they thought the marble would contact the floor after dropping off the table’s surface.  Before instruction, all students predicted that the marble would hit the floor in different spots – diametrically across from the launch point for no rotation, and at increasing distances from that first point with increasing rotation rates of the table (Figure 4). This is the exact misconception we aimed to elicit with this question: students were applying correct knowledge (“in the Northern Hemisphere a moving body will be deflected to the right”) to situations where this knowledge was not applicable: when observing the rotating body and the moving object upon it from an inert frame of reference.

Figure 4A: Depiction of the typical wrong answer to the question: Where would a marble land on the floor after rolling across a table rotating at different rotation rates? B: Correct answer to the same question. C: Correct traces of marbles rolling across a rotating table.

Figure 4A: Depiction of the typical wrong answer to the question: Where would a marble land on the floor after rolling across a table rotating at different rotation rates? B: Correct answer to the same question. C: Correct traces of marbles rolling across a rotating table.

In a second question, students were asked to imagine the marble leaving a dye mark on the table as it rolls across it, and to draw these traces left on the table. In this second question, students were thus required to infer that this would be analogous to regarding the motion of the marble as observed from the co-rotating frame of reference. Drawing this trajectory correctly before the experiment is run does not imply a correct conceptual understanding, since the transfer between rotating and non-rotating frames of references is not happening yet and students draw curved trajectories for all cases. However, after the experiment this question is useful especially in combination with the first one, as it requires a different answer than the first, and an answer that students just learned they should not default to.

The students’ laboratory reports supply additional support of the usefulness of this new approach.  These reports had to be submitted a week after doing the experiment and accompanying work sheets, which were collected by the instructors.  One of the prompts in the lab report explicitly addresses observing the motion from an inert frame of reference as well as the influence of the table’s rotational period on such motion. This question was answered correctly by all students. This is remarkable for three reasons: firstly, because in the previous year with conventional instruction, this question was answered incorrectly by the vast majority of students; secondly, from our experience, lab reports have a tendency to be eerily similar year after year which did not hold true for tis specific question; and lastly, because for this cohort, it is one of very few questions that all students answered correctly in their lab reports, which included seven experiments in addition to the Coriolis experiment. These observations lead us to believe that students do indeed harbor the misconception we suspected, and that the modified instructional approach has supported conceptual change.

CONCLUSIONS

We present modifications to a “very simple” experiment and suggest running it before subjecting students to more advanced experiments that illustrate concepts like Taylor columns or weather systems. These more complex processes and experiments cannot be fully understood without first understanding the Coriolis force acting on the arguably simplest bodies. Supplying correct answers to standard questions alone, e.g. “deflection to the right on the northern hemisphere”, is not sufficient proof of understanding.

In the suggested instructional strategy, students are required to explicitly state their expectations about what the outcome of an experiment will be, even though their presuppositions are likely to be wrong. The verbalizing of their assumptions aids in making them aware of what they implicitly hold to be true. This is a prerequisite for further discussion and enables confrontation and resolution of potential misconceptions. Wesuggest using an elicit-confront-resolve approach even when the demonstration is not run on an actual rotating table, but virtually conducted instead, for example using Urbano & Houghton (2006)’s Coriolis force simulation. We claim that the approach is nevertheless beneficial to increasing conceptual understanding.

We would like to point out that gaining insight from any seemingly simple experiment, such as the one discussed in this article, might not be nearly as straightforward or obvious for the students as anticipated by the instructor. Using an intriguing phenomenon to be investigated experimentally, and slightly changing conditions to understand their influence on the result, is highly beneficial. Probing for conceptual understanding in new contexts, rather than the ability to calculate a correct answer, proved critical in understanding where the difficulties stemmed from, and only a detailed discussion with several students could reveal the scope of difficulties.

ACKNOWLEDGEMENTS

The authors are grateful for the students’ consent to be featured in this article’s figures.

 

RESOURCES

Movies of the experiment can be seen here:

Rotating case: https://vimeo.com/59891323

Non-rotating case: https://vimeo.com/59891020

Using an old disk player and a ruler in absence of a co-rotating camera: https://vimeo.com/104169112

 

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Crouch, C. H., Fagen, A. P., Callan, J. P., and Mazur. E. 2004. Classroom Demonstrations: Learning Tools Or Entertainment?. American Journal of Physics, Volume 72, Issue 6, 835-838.

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Durran, D. R. and Domonkos, S. K. 1996. An apparatus for demonstrating the inertial oscillation, BAMS, Vol 77, No 3

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Endnotes

[i]While tremendously helpful in visualizing an otherwise abstract phenomenon, using a common rotating table introduces difficulties when comparing the observed motion to the motion on Earth. This is, among other factors, due to the table’s flat surface (Durran and Domonkos, 1996), the alignment of the (also fictitious) centrifugal force with the direction of movement of the marble (Persson, 2010), and the fact that a component of axial rotation is introduced to the moving object when launched. Hence, the Coriolis force is not isolated. Regardless of the drawbacks associated with the use of a (flat) rotating table to illustrate the Coriolis effect, we see value in using it to make the concept of fictitious forces more intuitive, and it is widely used to this effect.

[ii]Despite their popularity in geophysical fluid dynamics instruction at many institutions, rotating tables might not be readily available everywhere. Good instructions for building a rotating table can, for example, be found on the “weather in a tank” website, where there is also the contact information to a supplier given: http://paoc.mit.edu/labguide/apparatus.html. A less expensive setup can be created from old disk players or even Lazy Susans, or found on playgrounds in form of merry-go-rounds. In many cases, setting the exact rotation rate is not as important as having a qualitative difference between “slow” and “fast” rotation, which is very easy to realize. In cases where a co-rotating camera is not available, by dipping the marble in either dye or chalk dust (or by simply running a pen in a straight line across the rotating surface), the trajectory in the rotating system can be visualized. The instructional approach described in this manuscript is easily adapted to such a setup.

[iii]We initially considered starting the lab session by throwing the marble diametrically across the rotating table.  Students would then see on-screen the curved trajectory of a marble, which had never made physical contact with the table rotating beneath it, and which was clearly moving in a straight line from thrower to catcher, leading to the realization that it is the frame of reference that is to blame for the marble’s curved trajectory. However, the speed of a flying marble makes it very difficult to observe its curved path on the screen in real time. Replaying the footage in slow motion helps in this regard.  Yet, replacing direct observation with recording and playback seemingly hampers acceptance of the occurrence as “real”. We therefore decided to only use this method to further illustrate the concept, not as a first step.

 

Bios

Dr. Mirjam Sophia Glessmer, holds a Master of Higher Education and Ph.D. in physical oceanography. She works at the Leibniz Institute of Science and Mathematics Education in Kiel, Germany. Her research focus lies on informal learning and science communication in ocean and climate sciences.

Pierre de Wet is a Ph.D. student in Oceanography and Climatology at the University of Bergen, Norway, and holds a Master in Applied Mathematics from the University of Stellenbosch, South Africa. He is employed by Akvasafe AS, where he works with the analysis and modelling of physical environmental parameters used in the mooring analysis and accreditation of floating fish farms.

Of timeless relevance: the ESWN mentoring map and how you can provide mentoring to others at any career stage

Me realizing that there are three cameras aimed at me simultaneously at some point during my presentation (Picture: Sara Siebert)

This week I had the honor to be invited to give a talk to a network of PhD students of the three Leibniz institutes in Kiel, which is just forming. Being as big a fan of networking as I am, of course I could not say no to this opportunity, especially since I had a really good resource to share: The Earth Science Women’s Network‘s mentoring map.

The mentoring map is a tool that helps you think about what your mentoring needs are and whether you have a strategy in place to get those needs met. And if you realize you don’t — well, then you might want to read our 2013 chapter to get ideas on what strategies you might want to consider to find intellectual community, sponsors, emotional support, or whatever you just realized you are missing.

Even though during that presentation my focus was on conveying the different kinds of mentoring needs you might have at different points during your PhD journey and beyond, and then on identifying people and resources who might help you meet those needs, one point that I tried to make is that mentoring is not a one-way street. In my experience the best networking advice (and, by building an amazing network around you, also the best advice for how to make sure you have your mentoring needs met) is to pay it forward, to provide to others what you would wish that others provide to you.

Be the kind of person that you would love to have in your own network

This last piece of advice at first sounds like it is really difficult to put into action, and almost unattainable if you are just starting out with your PhD. But it is not. There are so many ways in which you can provide value to others around you, and have that become a habit. A couple of examples, in no particular order:

  • Offer to proof-read other people’s writing. Especially when you are just starting out, forcing yourself to read something really carefully, even though it might not be 100% what you need to be reading for your own research, is a great way to widen your horizon and pick up on what you like and don’t like in texts. And if you have to look up grammar rules to make sure your edits are correct — even better, you just learned something for your own writing!
  • Check in on people, ask how they are doing, and actually listen to their response. Sometimes only one person noticing that something is off makes a huge difference to someone
  • If you come across interesting articles, summer schools, blog posts, twitter profiles, … that remind you of something you talked about with someone or that you think might be interesting to them, just forward it. It takes a couple of seconds on your end, and even if they already got that information through some other route, they will appreciate the thought and effort and are a lot more likely to return the favor next time they see something that might be interesting to you
  • Be open about your own ideas, and always give credit to others if you talk about their ideas in front of others
  • If you have a network of any kind that might be interesting to others, offer to share it with them. Bring them with you to your work so they can meet interesting colleagues over coffee, give them your mom’s phone number because she can give advice on a topic they are struggling with (Danke, Joke, es ist nicht vergessen), send introductory messages for them
  • Similarly, if you have visibility in an area where they are trying to build it, ask them if they would like to write a guest post on your blog, or retweet their tweets to expose your followers to this new and interesting person, or ask them if they want to present a workshop with you
  • Follow up with people! Just sending an email saying “Hi! We met at conference x and talked about y and I just wanted to follow up so we can stay in touch” is so much more than most people do, but it has started an interaction that both of you are more likely to remember than if you never followed up
  • Remember that most people you meet feel at least as awkward about not knowing you as you feel about not knowing them. Just introduce yourself and maybe ask if they would like to have a coffee sometime! If you’ve been in your job for two weeks and feel like the complete newbie, chances are you still know so much more than the person whose first day it is today and they’d be super grateful if you took them under your wing and showed them how to operate the photocopy machine

What else are habits you would recommend people develop so they become the kind of person you would like to have in your own network? Let me know in the comments!

P.S.: Just have to show the pictures below because it makes me proud that there is so much social media activity going on now at my former workplace :-)

Need your help! “Wish list” for a student lab for tank experiments?

I’d love your input: If your student lab for GFD tank experiments had to downsize, but you had to present a “wish list” for a smaller replacement, what would be on that list? Below are my considerations, but I would be super grateful for any additional input or comments! :-)

Background and “boundary conditions”

The awesome towing tank that you have come to love (see picture above) will have to be removed to make room for a new cantina. It might get moved into a smaller room, or possibly replaced all together. Here are some external requirements, as far as I am aware of them:

  • the (new) tank should ideally be movable so the (small) room can be used multi-purpose
  • since the new room is fairly small, people would be happy if the new tank was also smaller than the old one
  • the rotating table is kept (and a second, smaller one, exists in the building)
  • There are other, smaller tanks that will be kept for other experiments, dimensions approximately 175x15x40cm and smaller
  • the whole proposal needs to be inexpensive enough so that the likelyhood that it will actually be approved is moderate to fair ;-)

Here are a couple of things I think need to be definitely considered.

Dimensions of the tank

If the tank was to be replaced by a smaller one, how small could the smaller one be?

The dimension of the new tank depend, of course, on the type of experiment that should be done in the tank. Experiments that I have run in the tank that is to be replaced and that in my opinion should definitely be made possible in the new location/tank include

  1. “Dead water”, where a ship creates internal waves on a density interface (instructions)
  2. Internal lee waves & hydraulic jumps, where a mountain is moved at the bottom of the tank (instructions)
  3. Surface imprints of internal waves (example)
  4. Surface waves (example)
  5. Intrusions (example)
  6. Waves in a density stratification (example)
  7. Surface waves running up on a slope (I haven’t blogged about that yet, movies waiting to be edited)

If we want to be able to continue running these experiments, here is why we should not sacrifice the dimensions of the tank.

Why we need the tank length

The first reason for keeping the length of the tank is that the “mountains” being towed to create the lee waves are already 1 and 1.5m long, respectively. This is a length that is “lost” for actual experiments, because obviously the mountain needs space inside the tank on either end (so in its start and end position). Additionally, when the mountain starts to move, it has to move for some distance before the flow starts displaying the features we want to present: Initially, there is no reservoir on the “upstream” side of the mountain and it only builds up over the first half meter or so.

The second reason for keeping the length of the tank are wave reflections once the ship or mountain comes close to the other side of the tank. Reflected surface waves running against the ship will set up additional drag that we don’t want when we are focussing on the interaction between the ship and the internal wave field. Reflected internal waves similarly mess things up in both experiments

The third reason for keeping the length of the tank is its purpose: as teaching tank. Even if one might get away with a slightly shorter tank for experiments when you just film and investigate the short stretch in the middle of the tank where there are no issues with either the push you gave the system when starting the experiment or the reflections when you get near the end, the whole purpose of the tank is to have students observe. This means that there needs to be a good amount of time where the phenomenon in question is actually present and observable, which, for the tank, means that it has to be as long as possible.

Why we need the tank width

In the experiments mentioned above, with exception of the “dead water” experiment, the tank represents a “slice” of the ocean. We are not interested in changes across the width of the tank, and therefore it does not need to be very wide. However, if there is water moving inside the tank, there will be friction with the side walls and the thinner the tank, the more important the influence of that friction will become. If you look for example at the surface imprint of internal wave experiment, you do see that the flow is slowed down on either side. So if you want flow that is outside of the boundary layers on either side, you need to keep some width.

Secondly, not changing the tank’s width has the advantage that no new mountains/ships need to be built.

Another, practical argument for a wide-ish tank (that I feel VERY strongly about) is that the tank will need to be cleaned. Not just rinsed with water, but scrubbed with a sponge. And I have had my hands inside enough tanks to appreciate if the tank is wide enough that my arm does not have to touch both sides at all times when reaching in to clean the tank.

Why we need the tank depth

The first reason for keeping the height is that for the “dead water” experiment, even the existing tank is a lot shallower than what we’d like from theory (more here). If we go shallower, at some point the interactions between the internal waves and the ground will become so large that it will mess up everything.

Another reason for keeping the depth is the “waves running up a slope” experiment. If you want waves running up a slope (and building up in height as they do), you have the choice between high walls of the tank or water spilling. Just sayin’…

And last not least: this tank has been used in “actual” research (rather than just teaching demonstrations, more on that on Elin’s blog), so if nothing else, those guys will have thought long and hard about what they need before building the tank…

Historical images of research on internal lee waves being done with the tank

Without getting too philosophical here about models and what they can and cannot achieve (and tank experiments being models of phenomena in the ocean), the problem is that scaling of the ocean into a tiny tank does not work, so “just use a mountain/boat half the size of the existing ones!” is actually not possible. Similarly to how if you build the most amazing model train landscape, at some point you will decide that tiny white dots are accurate enough representations of daisies on a lawn, if you go to a certain size, the tank will not be able to display everything you want to see. So going smaller and smaller and smaller just does not work. A more in-depth and scientific discussion of the issue here.

Other features of the tank

When building a new tank or setting up the existing tank in a new spot, there are some features that I consider to be important:

  • The tank needs a white, intransparent back wall (either permanently or draped with something) so that students can easily focus on what is going on inside the tank. Tank experiments are difficult to observe and even more difficult to take pictures of, the better the contrast against a calm background, the better
  • The tank should be made of glass or some other material that can get scrubbed without scratching the surface. Even if there is only tap water in the tank, it’s incredible how dirty tanks get and how hard they have to be scrubbed to get clean again!
  • The tank needs plenty of inlets for source waters to allow for many different uses. With the current tank, I have mainly used an inlet through the bottom to set up stratifications, because it allowed for careful layering “from below”. But sometimes it would be very convenient to have inlets from the side close to the bottom, too. And yes, a hose could also be lowered into the tank to have water flow in near the bottom, but then there needs to be some type of construction on which a hose can be mounted so it stays in one place and does not move.
  • There needs to be scaffolding above the tank, and it needs to be easily modifiable to mount cameras, pulleys, lights, …
  • We need mechanism to tow mountains and ships. The current tank has two different mechanisms set up, one for mountains, one for ships. While the one for the ship is home-made and easily reproducible in a different setting (instructions), the one to tow the mountain with is not. If there was a new mechanism built, one would need to make sure the speeds at which the mountain can be towed matches the internal wave speed to be used in the experiment, which depends on the stratification. This is easy enough to calculate, but it needs to be done before anything is built. And the mechanism does require very securely installed pulleys at the bottom of the tank which need to be considered and planned for right from the start.

“Source” reservoirs

The “source” reservoirs (plural!) are the reservoirs in which water is prepared before the tank is filled. It is crucial that water can be prepared in advance; mixing water inside the tank is not feasible.

There should be two source reservoirs, each large enough to carry half the volume of the tank. This way, good stratifications can be set up easily (see here for how that works. Of course it works also with smaller reservoirs in which you prepare water in batches as you see below. But what can happen then is that you don’t get the water properties exactly right and you end up seeing stuff you did not want to see, as for example here, which can mess up your whole experiment)

Both reservoirs should sit above the height of the tank so that the water can be driven into the tank by gravity (yes, pumps could work, too, more on that below).

“Sink” reservoir

Depending on the kind of dyes and tracer used in the water, the water will need to be collected and disposed of rather than just being poured down the drain. The reservoir that catches the “waste” water needs to

  • be able to hold the whole volume of the tank
  • sit lower than the tank so gravity will empty the tank into the reservoir (or there needs to be a fast pump to empty the tank, more on that below)
  • be able to be either transported out of the room and the building (which means that doors have to be wide enough, no steps on the way out, …) or there needs to be a way to empty out the reservoir, too
  • be able to either easily be replaced by an empty one, or there needs to be some kind of mechanism for who empties it within a couple of hours of it being filled, so that the next experiment can be run and emptied out

If the waste water is just plain clear tap water, it can be reused for future experiments. In this case, it can be stored and there need to be…

Pumps

If reservoirs cannot be located above and below tank height to use gravity to fill and empty the tanks, we need pumps (plural).

  • A fast pump to empty out the tank into the sink reservoir, which can also be used to recycle the water from the sink reservoir into the source reservoirs
  • One pump that can be regulated very precisely even at low flow rates to set the inflow into the tank
  • Ideally, a second pump that can be regulated very precisely, so the double bucket method of setting up a stratification in a tank can be done automated rather than relying on gravity.

Preferable the first and the latter are not the same, because changing settings between calibrating the pump for an experiment, setting it on full power to empty the tank, and calibrating it again will cause a lot of extra work.

Inlets for dyes

Sometimes it would be extremely convenient if there was a possibility to insert dyes into the tank for short, distinct periods of time during filling to mark different layers. For this, it would be great to be able to connect syringes to the inlet

Hoses and adapters

I’ve worked for years with whatever hoses I could find, and tons of different adapters to connect the hoses to my reservoir, the tap, the tank. It would be so much less of a hassle if someone thought through which hoses will actually be needed, bought them at the right diameter and length, and outfitted them with the adapters they needed to work.

Space to run the experiment

The tank needs to be accessible from the back side so the experimenter can run the experiment without walking in front of the observers (since the whole purpose of the tank is to be observed by students). The experimenter also needs to be able to get out from behind the tank without a hassle so he or she can point out features of interest on the other side.

Also, very importantly, the experimenter needs to be able to reach taps very quickly (without squeezing through a tight gap or climbing over something) in case hoses come loose, or the emergency stop for any mechanism pulling mountains in case something goes wrong there.

Space for observers

There needs to be enough room to have a class of 25ish students plus ideally a handful of other interested people in the room. But not only do they need to fit into the room, they also need to be able to see the experiments (they should not have to stand in several rows behind each other, so all the small people in the back get to see are the shoulders of the people in front). Ideally, there will be space so they can duck down to have their eyes at the same height as the features of interest (e.g. the density interface). If the students don’t have the chance to observe, there is no point of running an experiment in the first place.

Filming

Ideally, when designing the layout of the room, it is considered how tank experiments will be documented, i.e. most likely filmed, and there needs to be space at a sufficient distance from the tank to set up a tripod etc..

Lighting

Both for direct observations and for students observing tank experiments, it is crucial that the lighting in the room has been carefully planned so there are minimal reflections on the walls of the tank and students are not blinded by light coming through the back of the tank if a backlighting solution is chosen.

Summary

In my experience, even though many instructors are extremely interested in having their students observe experiments, there are not many people willing to run tank experiments of the scale we are talking about here in their teaching. This is because there is a lot of work involved in setting up those experiments, running them, and cleaning up afterwards. Also there are a lot of fears of experiments “going wrong” and instructors then having to react to unexpected observations. Running tank experiments requires considerable skill and experience. So if we want people using the new room and new tank at all, this has to be made as easy as possible for them. Therefore I would highly recommend that someone with expertise in setting up and running experiments, and using them in teaching, gets involved in designing and setting up the new room. And I’d definitely be willing to be that person. Just sayin’ ;-)

“Continue. Start. Stop.”. An article supporting the usefulness of my favourite method of asking for student feedback on a course!

I’ve been recommending the “Continue. Start. Stop.” feedback method for years an years (at least since my 2013 blog post), but not as a research-backed method but mostly based on my positive personal experience with it. I have used this method to get feedback on courses I’ve been teaching a couple of weeks into the course in order to improve my teaching both within the course as well as over the years. If there was anything that students thought would improve their learning, I wanted to be able adapt my teaching (and also, in a follow-up discussion of the feedback, be able to address student expectations that might not have been explicit before that I might or might not want to follow). I like that even though it’s a qualitative method and thus fairly open, it gives students a structure along which they can write their feedback. Also by asking what should be continued as well as stopped and started, it’s a nice way to get feedback on what’s already working well, too! But when I was asked for a reference for the method today, I didn’t really have a good answer. But then I found one: an article by Hoon et al. (2015)!

Studies on the “continue. start. stop.” feedback vs open feedback

In the first study in the article, two different feedback methods are compared over three different courses: a free form feedback and a structured format, similar to “continue. start. stop.”. From this study, the authors draw pointers for changing the feedback method in the free form course to a more structured feedback. They investigate the influence of this change in a second study.

In that second study, the authors find that using a structured feedback led to an increasing depth of feedback, and that the students liked the new form of giving feedback. They also find indications that the more specific the questions are, the more constructive (as compared to more descriptive texts in the open form; not necessarily more positive or negative!) the feedback is.

My recommendations for how to use the “continue. start. stop.” feedback

If anything, this article makes me like this feedback method even more than I did before. It’s easy and straight forward and actually super helpful!

Use this as formative feedback!

Ask for this feedback early on in the course (maybe after a couple of weeks, when students know what to expect in your course, but with plenty of the course left to actually react to the feedback) and use the student replies to help you improve your teaching. While this method can of course also be used as summative feedback at the end of the course, how much cooler is it if students can benefit from the feedback they gave you?

Ask full questions

One thing that I might not have been clear about before when talking about the “continue. start. stop.” feedback method is that it is important to actually use the whole phrases (“In order to improve your learning in this course, please give me feedback on the following points

  1. Continue: What is working well in this course that you would like to continue?
  2. Start: What suggestions do you have for things that could improve the course?
  3. Stop: What would you like us to stop doing?”

or similar) rather than just saying “continue. start. stop.” and assuming the students know what that means.

Leave room for additional comments

It is also helpful to give an additional field for other comments the students might have, you never know what else they’d like to tell you if only they knew how and when to do it.

Use the feedback for several purposes at once!

In the article’s second study, a fourth question is added to the “continue. start. stop.” method, and that is asking for examples of good practice and highlights. The authors say this question was mainly included for the benefit of “external speakers who may value course feedback as evidence of their own professional development and engagement with education”, and I think that’s actually a fairly important point. While the “continue. start. stop.” feedback itself is a nice addition to any teaching portfolio, why not think specifically about the kind of things you would like to include there, and explicitly ask for them?

Give feedback on the feedback

It’s super important that you address the feedback you got with your class! Both so that they feel heard and know whether their own perception and feedback agrees with that of their peers, as well as to have the opportunity to discuss what parts of their suggestions you are taking on, what will be changing as a result of their suggestions, and what you might not want to change (and why!). If this does not happen, students might not give you good feedback the next time you ask for it because they feel that since it didn’t have an effect last time, why would they bother doing it again?

Now it’s your turn!

Have you used the “continue. start. stop.” method? How did it work for you? Will you continue using it or how did you modify it to make it suit you better? Let me know in the comments below! :-)

Reference:

Hoon, A. and Oliver, E.J. and Szpakowska, K. and Newton, P. (2015) ‘Use of the ‘Stop, Start, Continue’ method is associated with the production of constructive qualitative feedback by students in higher education.’, Assessment and evaluation in higher education., 40 (5). pp. 755-767. [link]

Taking ownership of your own mentoring

Have you ever had questions related to your career development that you didn’t know who to ask for answers for? Or have you ever felt that you would probably profit from having a mentor, but didn’t know who that mentor could be? Or do you have a great mentor but wonder whether you might be relying too heavily on him or her? Then this post is for you!

(This post, and the article referenced at the bottom, are heavily inspired by the work of Kerry Ann Rockquemore, especially this post, and workshops she gave for the Earth Science Women’s Network.)

So. Let’s get started. Do you even know what your current mentoring needs are? In the image below we suggest different kinds of mentoring needs that you will probably all encounter throughout your career, hopefully not all at the same time.

It is really helpful to try and identify a person for each of those fields that might possibly be able to help. If you fill out the blank spaces in the graphic below now, before you actually urgently need someone to fill a specific role, it’ll be very valuable once the time comes!

Mentoring_map_01

A “mentoring map” to help you identify your mentoring needs as well as who might be able to fill those needs.

If you aren’t quite sure what each of the fields above contains, the image below might give you ideas:

Mentoring_map_02

Mentoring map. What exactly are your mentoring needs?

And now that you know what your needs are, how do you actually identify possible mentors for each category? We give some ideas in the image below!

Mentoring_map_03

Mentoring map and where to find possible mentors for the different mentoring needs

Do you feel like you are taking unfair advantage of your mentors? Then maybe think about paying it forward. Be a sponsor to the student that stands out in your class and recommend her for a scholarship. Be the safe space your friend needs. Give substantial feedback on your office mate’s paper. Even if you feel you are nowhere near ready to “be someone’s mentor”, that is probably not true. Give back when the opportunity arises, and don’t feel bad to ask for the mentoring you need!

For more details, check out our article:

Glessmer, M.S., A. Adams, M.G. Hastings, R.T. Barnes, Taking ownership of your own mentoring: Lessons learned from participating in the Earth Science Women’s Network, published in The Mentoring Continuum: From Graduate School Through Tenure, Syracuse University Graduate School Press, ed. Glenn Wright, 2015.

Pdf of the chapter here.

P.S.: This text originally appeared on my website as a page. Due to upcoming restructuring of this website, I am reposting it as a blog post. This is the original version last modified on November 4th, 2015.

I might write things differently if I was writing them now, but I still like to keep my blog as archive of my thoughts.