current – Adventures in Oceanography and Teaching

Totally not the focus of our experiments, but so beautiful! Kelvin-Helmholtz instabilities

mglessmer — Fri, 22 Sep 2017 10:56:48 +0000

This is really not the focus of our experiments here in Grenoble, but they are too nice not to show: Kelvin-Helmholtz instabilities! They showed up really nicely in our first experiment, when we only had neutrally-buoyant particles in our source water (and not yet in the ambient water). The water that shows up as the […]

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Standing waves in a current

mglessmer — Thu, 04 May 2017 11:13:33 +0000

The other day I found the perfect standing waves on a current: This egg-carton-like pattern really stays pretty constant over time and I think the changes in the wave pattern are mostly due to changes in the sand bed below! You see the sharp edge that is currently being eroded, and sometimes you catch bits […]

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Another wave hunt expedition: Learning to discover ocean physics wherever you go

mglessmer — Tue, 21 Jun 2016 11:06:21 +0000

One of my favourite topics right now: Learning to “see” ocean physics wherever you go. For example here: A visit to my goddaughter in Schleswig, and this time we are practicing all she and her mom read about in MY BOOK (and if you have good ideas for a title for that book, please let me know!). […]

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Reading ice on a river as tracer for flow fields

mglessmer — Thu, 21 Jan 2016 11:44:07 +0000

For most of my readers it might be pretty obvious what the movement of floating ice says about the flow field “below”, but most “normal” people would probably not even notice that there is something to see. So I want to present a couple of pictures and observations today to help you talk to the people around […]

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Flow separation

mglessmer — Mon, 27 Apr 2015 10:49:52 +0000

On the way to the pool I cross over the Elbe river on this pretty bridge. Which is pretty spectacular, just because the structure itself is so amazing. But what is even more spectacular is how every time I am there I see new things in the flow field. And the example I want to […]

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Waves on a current

mglessmer — Mon, 20 Apr 2015 11:36:14 +0000

When you throw a stick in the water and the waves don’t form circles. Throwing something in the water usually results in waves traveling out in circles from the point of impact. But if you throw your stick into a current, the waves get distorted. Watch the movie below! Slightly confusing that the stick drifts […]

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Wave fields around objects in a channel

mglessmer — Wed, 25 Feb 2015 12:35:48 +0000

One of the reasons I have been wanting to do the vortex street experiment I wrote about on Monday is that it is pretty difficult to visualize flow fields (especially if you neither want to pollute running water somewhere in nature, nor want to waste a lot of water by setting up the flow yourself). As a first order […]

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Wind waves meet current

mglessmer — Tue, 08 Apr 2014 05:02:22 +0000

Wind waves on one side of the current – no waves on the other. Recently in Bergen, I was walking to meet up with a friend at the kayak club, and I had to cross a bridge that has always fascinated me. Underneath the bridge, there is only a very narrow opening connecting basically the […]

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