Category Archives: wave watching


Today’s #WaveWatchingWednesday is a recap of one of the most amazing experiences ever: A freediving trip to Dahab. Even though we have been back for more than a week now, I am still processing all the new impressions — the sea, the colors, the snorkling (and for those who need to hear it: no, looking at “the elephant” at 25 meters depth does NOT count as “snorkling”! ;-)), the desert, the people, the sounds and smells, the challenges that I took on and mastered, the challenges I did not take, the PBs, the feeling of accidentally having fallen into a fish tank, the “special tea”, seeing all the places I had heard so much about and seen in so many documentaries, the water, the amazing friends I travelled & dived with, their support and encouragement, my instructor Anja’s wise words… I will need more time to process everything, but here are some pictures (out of several thousand that I took!). Enjoy!

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24 days of #KitchenOceanography — now available as a book!

For all of you who know and love my “24 days of #KitchenOceanography” series (and for those who need to quickly look up what that was about and then fall in love with it ;-)) — you can now buy it as a book!

The book contains 24 easy experiments, embedded in the bigger context of the world ocean, that can be done using only common household items.

Remember, the 24 #KitchenOceanography experiments also work very well as an advent calendar!

Total internal reflection

In the “static apnea” discipline in freediving, many cool pictures of athletes are taken underwater in a way that plays with the reflection of the athlete in the still water surface. This can lead to pretty spooky pictures (like the one of Victor in the top left). We do have other experiences with water, where there are areas where we can look in (or out), but then others where we can’t: In the bottom left, you see Mats and his shadow, even the individual tiles very clearly in the water. But the further back you look, the more you notice that the picture was taken from outside the water, because you start seeing more reflections in the water surface. In the bottom right, taken from within the water, you see reflections of all the divers and the lane markings in the surface except right at Edvin’s elbow, where we look out of the water and see what’s happening above the pool. And then in the top right, we don’t see the water surface at all — the only reason we know we are looking at Alex from within the water is that there are bubble rings floating between us and him. So what is going on here?

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