Tsunamis learning activity

Tsunamis in simple form a splash of water.

Materials

Square or rectangle shaped Tub 

Water

Objects to put or drop into water.

Set of dominoes, the more the merrier

Ping Pong ball or other light weight ball

12 inch by half inch piece of paper per student

one or two bricks or large flat rocks

Non water based markers

I first started learning about tsunamis while doing dishes at mom's command. So should you be asked to do dishes, it is not a chore but a chance to observe small tsunamis in action.

OR with a parent or guardian watching.

On a nice warm or even hot day take a tub that can hold water outside and drag out the water hose to a open area that can be flooded with water. Find other objects to drop into, float on, or push the water in the tub around with.

First fill the tub with water all the way to the top. This is the ocean. Now drop in a large object. What happens? The large object pushed water aside as it entered the full tub of water. That water had to go some where. That somewhere was out of the tub. No matter how careful you are, if your tub of water is full as can be. Anything else added will cause a flood of some sort and water will move from the tub to the area around it. 

How many different ways can you force water out of the tub? Don't refill the tub until  you can't splash any water out at all. Then try this activity again, this time placing dry objects around the tub. Can you form a wave that will get only the objects on one side wet? Two sides wet? Three sides? How do you control your waves?

If you have some way to make the surface of the water in the tub level with a surface that you can place different objects on, try the same activity above again.

With a tsunami some sort of land movement has caused a section of land to shove push on a section of water.  that section of water pushes on other sections of water and so on.

You can see how this happens if you line up the dominoes so that if one falls over it pushes the next, which pushes the next. If you set up the dominoes so that they run into a wall the wave stops. What happens to the last domino? what happens if you set up the dominoes so that each one barley touches the next when it has fallen? Set up the dominoes so that they are close together and place the ping pong ball at the far end of the line of dominoes then make the earth quake that starts your tsunami. What happens to your ball? Set up the dominoes so that each domino just touches the next. Set the ping pong ball at the end and start your Tsunami. What is the difference? Why?

The damage a Tsunami does depends on how much water is pushed when the Tsunami is first started. How hard that water is pushed, and how long in needs to travel before it hits something.  

Give each student a piece of paper 12 inches long by half an inch wide. Have them make a circle with the paper. A Tsunami moving through the ocean is much like this loop of paper. Make a small tab at each end of the paper by folding about half an inch upwards. Form the loop again on a table, holding one tab with one hand and sliding the other tab along the table top. The tsunami is changing shape. If this were a ball of water it would spread out. Move your piece of paper so that it is about 6 inches from a wall and do the same thing. Here there is more water than can spread out. The flood will be thin as thin or shallow as the paper is because it has a huge place to spread out on. Have one student hold the tabs closer together and then an other push down on the top of the loop to make a table like form. In this model the Tsunami has come to a smaller area so if it made a flood taller than the first model where the paper was had room to lie flat.

 Stretch the piece of paper out on a flat surface or table and tape one end of the paper down. Slide the free end along the surface the table towards the taped end. Gently keep moving the free end up and over the taped end. How does the shape of the paper change? Why? 

Back to the tub of water. Measure and draw a line about two or three inches up the sides of the tub.  Add water to this line. 

This time add a glass of water to the tub. Pour the glass in slowly. What happens. Return the level of water to be even with the line. Pour different amounts at different speeds. Watch happens.  

Can you control how the water acts in the tub? Can you make it splash? Can you make the water rise fast but with out a splash?

Build an island with the bricks or rocks in the center of the tub. Add water half way up the island, mark the water level on the side of the tub. Add water again, and observe what happens. If you place your island in a corner or near the side of the of the tub how does this change what happens to your island and the town on it?

Now we have learned a bit about Tsunamis do you think you would want to build a home right down near the ocean? As for me I'll build high and drive to the beach. Then park with the front of my car pointed away from shore, and pin the car key to my shirt!