Alex Gendler’s TED-Ed Lesson “How tsunamis work” gives a thorough introduction to the towering terror of tsunamis, offering a comprehensive look at the history and science behind these swells. Here, we’ve broken down how these waves form in a series of animated GIFs.

Tsunamis are caused by energy originating underwater from a volcanic eruption, a submarine landslide, or, most commonly, an earthquake on the ocean floor.

1. For example, the tectonic plates of the Earth’s surface slip, releasing a massive amount of energy into the water.
2. This energy travels up to the surface, displacing water and raising it above the normal sea level.
3. Gravity pulls that energy back down.
4. As a result, the energy ripples outwards horizontally.

Thus, the tsunami is born, moving at over 500 miles per hour.

To see the whole lesson, click here. >>
To check out TED-Ed’s Tumblr, which is full of more animated GIFs from our lessons, click here. >>