Question: What causes a tsumnami?

Sarah Martin answered on 19 Jun 2012:

Hi meg!

See my answer to the earthquake question first please! Tsunamis happen when crust plates move suddenly under the ocean – a bit like if when you sit in the bath with your knees up and then suddenly straighten your legs – the water gets disturbed and really large waves result! These waves spread out and run until they reach shores, where they get even bigger as they run up into shallow waters.

That’s it!

🙂 Sarah