Tsunamis
Know what a tsunami is: a very large, fast ocean wave caused by an earthquake or volcanic eruption under the sea, which can cause great damage when it reaches land
What a learner can do afterwards
- Explain that a tsunami is caused by an earthquake or eruption under the sea
- State that tsunamis travel very fast across the ocean
- Describe the damage a tsunami can cause when it reaches the coast
The lesson
A tsunami is a giant, fast wave in the ocean. It is not caused by wind or storms. It starts when the sea floor suddenly jolts, often during a strong earthquake or an underwater volcano eruption. That jolt pushes a huge amount of water outward.
Far out at sea, a tsunami can look like a low, wide bump. Ships may not even notice it go by. But as it nears the coast, the water gets shallow. The wave slows down and grows much taller.
One day, the ocean floor shakes hard during an earthquake far from shore. Minutes later, the sea pulls back strangely from the beach. Then a wall of water rushes in. It floods streets, knocks over cars, and damages buildings near the shore.
If people ever hear a tsunami warning, they move to higher ground right away. A tsunami can arrive faster than you expect.
A tsunami is a huge, fast wave caused by an earthquake or eruption under the sea, and it can badly damage the coast when it arrives.
Watch it
Where it sits
This opens up
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.