1. Question: What causes ocean tides?

2. Standard: Recognize the significant role of water in Earth’s processes. Essential Question: How do currents move water?

3. Ocean Currents Lab Problem: What things affect the flow and direction of a current in a simulated model? Materials: Shallow tray with water Food coloring in a beaker Cup Rock pipette towels

4. Activity 1—Global Winds Carefully fill the tray with water. Let the water settle. Place a few drops of food coloring at one end of the tray, being careful not to “push” the water with your pipette. Gently blow across the tray. 1. Observe and sketch 2. Where do the currents move rapidly? 3. What happens to the water as it moves away from the wind source?

5. Activity 2--Landmasses Place a cup upside down in the middle of the tray. Put the rock on top to weigh down the cup. The cup represents an island. Add a few drops of food coloring in the front of the island and gently blow across the tray. 1. Observe and sketch. 2. What effect does the island have on the current? 3. Is the current stronger in front of or behind the island. How can you tell?

6. Activity 3 –Geography of coastlines Change the water if needed. Take out the cup and place the rock in the water. This models a natural coastline with an irregular shape. Add a few drops of food at one end of the tray and blow across the tray. 1. Observe and sketch 2. Are the currents more or less complex with the irregular shaped object? 3. Do the currents always move in the direction of the wind?

7. Activity 4—Rotation of the Earth and Coriolis Effect Change the water if needed. Add a few drops of food coloring in a pie pan. Gently turn the pan while blowing in one direction. List 3 things that might influence the movement of currents in the ocean.

8. What’s the difference between waves and currents? Watch a Studyjams videoStudyjams