Hydrothermal springs that you can visit without a deep-sea submersible.

When teaching about hydrothermal springs, I usually use a video a friend of mine took of hydrothermal vents on the mid-Atlantic ridge on the WHOI submersible Alvin. But being on Iceland now, there is much better material available which students can even go and experience themselves.

In the Blue Lagoon close to Reykjavik.

I am too chicken to take my camera under water in the Blue Lagoon to film the hot springs, but there are other hot springs all over Iceland that are less scary, for example this one that my friend Astrid found in the middle of a meadow.

View from the top into the hot spring – do you see the bubbles breaking the surface?

And here I even dared take my camera under water.

View of the hot spring under water – that’s where the bubbles come from!

Granted, this is not quite as impressive as a black smoker or the Blue Lagoon. But the water in the whole little lake was warmer than about 40 degrees Celsius, and the hot spring is sitting randomly in a field. That’s hand-on geothermal heating for you!