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Ocean Currents LAB #7. Science 6 Oceans. What is a Current?. A current is a continuous flow of water in a given direction A current is like a river in the ocean. Causes of Surface Currents. Three things cause surface currents: Wind 2. Continents
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Ocean CurrentsLAB #7 Science 6 Oceans
What is a Current? A current is a continuous flow of water in a given direction A current is like a river in the ocean
Causes of Surface Currents Three things cause surface currents: • Wind 2. Continents 3. Rotation of the Earth, also known as the Coriolis Effect
Heating of the Earth’s Surface Explain how this causes winds.
Prevailing Winds Fig. 16.14, p.407
Lab #7 Surface Currents • Jobs • Materials – get bins from supply tables • Recorder (straw)– be certain everyone in the group is recording the information • Encourager (cinnamon)– be certain everyone participates and understands the information • Time Keeper (sand)– keep group focused on task and on time
Surface Ocean Currents • We know that surface ocean currents are caused by _____________________. • The plate of water you have represents the ocean. • The “cinnamon” person sprinkles a small amount of cinnamon (4 or 5 shakes) on the water. • What happens to the cinnamon?
Surface Ocean Currents - Wind • The “straw” person blows very gently through the straw onto the water surface. • Place straw on edge of plate at low angle • What do you observe? • What did your winds cause? • Did direction of the wind have an effect?
Depth of Surface Ocean Currents • The “sand” person sprinkles the sand over the water. • The “straw” person needs to blow gently over the surface of the water. • What happens to the cinnamon and the sand? • What does this suggest to you about the depth of surface currents?
Clean Your Plate • Watch the demonstration, then… • Carefully pour water into the tub and dry off plates.
Is there only water on Earth? Fig. 16-1, p.378
Land Masses Create Currents • What happens to ocean currents when they run into continents? • Listen for directions….
Land Masses Create Currents • With the clay make landforms such as islands, reefs, and small continents and place them on your plate. • On LAB #7 Part A, draw the landforms you created in your ocean.
Land Masses Create Currents • Sprinkle the surface of the water with cinnamon. • One person blows gently. Watch the direction the cinnamon flows. • Place an X on your activity sheet from where the wind originated and use arrows to draw the direction of the currents.
Clean Up • Pour water in tub and dry off plate. • Materials: return bins to supply table • All: wipe up table • Return to seats and put LAB #7 in binder • Next: • Cause - Effect Chart for Currents
LAB #7: The Coriolis Effect • Observe the currents on the next slide. • What do you see occurring? • Look at the direction of the gyres in each hemisphere.
Ocean Currents of the World Fig. 16-12, p.384
The Coriolis Effect • Locate the North Pole and the Equator on the Northern Hemisphere diagram. • You are looking down onto the Earth from above the North Pole. • On the arrows label west W and east E
The Coriolis Effect • One student holds plate • Another student turns the plate in a counterclockwise motion. • A third student draws a line from the North Pole to the Equator. • A fourth student draws a line from the Equator to the North Pole
The Coriolis Effect • Are the lines straight? • Why not? • If this line was an ocean current, which direction would it flow in the Northern Hemisphere? • clockwise
The Coriolis Effect • Locate the South Pole and the Equator on the Southern Hemisphere diagram. • You are looking down onto the Earth from above the South Pole. • On each end of the arrows label west W and east E
The Coriolis Effect • One student holds plate • Another student turns the plate in a clockwise motion. • A third student draws a line from the South Pole to the Equator. • A fourth student draws a line from the Equator to the South Pole
The Coriolis Effect • Are the lines straight? • Why not? • If this line was an ocean current, which direction would it flow in the Southern Hemisphere? • counterclockwise
The water of the ocean surface moves in a regular pattern called surface ocean currents. The currents are named. In this map, warm currents are shown in red and cold currents are shown in blue.
Clean Up • Materials - return bins • All - clean off tables • Return to seats