1. To identify, describe and list factors that control ocean currents
Purpose:
To identify, describe and list factors that control ocean currents
To explain how ocean currents affect climate in San Diego and the world

2. Warm-up
Imagine you are stranded on a desert island in the North Pacific Ocean. You stuff a distress “help” message in a bottle and throw it in the ocean, hoping someone in San Diego will get it.
Is it possible someone in San Diego will find your message and send help? Explain your answer.

3. Light decreases with depth! Temp also decreases with depth!
THERMOCLIME: transitional ocean layer
3 Layers : Warm Upper
Thermocline
Cold Lower

4. Surface Currents
Are stream like movements of water at the ocean’s surface. They are caused by the prevailing winds
Circulate thousands of miles across entire oceans

5. Surface Currents are influenced by:
Global winds
The Coriolis Effect
Continental deflections

6. Surface winds (purple arrows) create surface currents (red)
The Trade Winds move currents east to west along the Equator
The Westerlies move currents west to east in mid-latitudes

7. Ocean currents distribute heat throughout the depths of the ocean

8. The Coriolis Effect
Winds, ocean currents and moving objects appear to move in curved paths as the Earth rotates beneath

9. Coriolis Effect Demonstration: Northern Hemisphere
Draw 2 circles
Rotate the paper counterclockwise
Prediction:
Draw a straight line from a to b. Describe the result
Draw a straight line from c to d. Describe the result b d c

10. Continents cause surface currents to change directions

11. Surface currents affect climates of the world
The Gulf Stream brings warm water from the Equator to northern Europe
Warmer climates result in latitudes that are similar to Canada

12. Cold water from the north is carried southward by the California Current
The cold water current keeps the climate comfortable along the West Coast all year

13. What upwelling is
The rising of cold water from deeper layers which replaces warmer surface water along a shoreline
Upwelling Animation

14. What upwelling does
Brings more dissolved nutrients such as nitrates and phosphates to the ocean surface
Responsible for the booming marine life population off the coast of California, Peru, and western Africa

15. How upwelling happens Wind moves blows along the shore
Coriolis Effect causes warm surface water to move away from shore.
Cold water rises up from below to fill in the area the warm water leaves

16. El Nino:
is the change in the location of warm and cold surface water every 2-7 years
results in worldwide weather changes
causes heavy rains and mudslides in California and droughts in other regions

17. Normal weather patterns occur when warmer water is found in the western pacific near Asia

18. During El Nino, purple shows warmer water located near America in the eastern pacific.

19. Weather patterns across the USA and the world are changed

20. During El Nino years, the Trade Winds weaken and do not move warm water across the Pacific

21. Storms develop in the middle of the Pacific bringing heavy winter rain to San Diego

22. During El Nino, normally wet regions experience drought and wildfires

23. Other areas, like S. California experience intense wave damage from storms

24. Roads are destroyed and cliffs are eroded by waves and flooding

25. Homes are flooded. Diseases spread by contaminated water.

26. Accidents and injuries are greater with stormy weather

27. Dry riverbeds in Arizona flood, damaging homes in Arizona

28. Saturated hills slide, creating hazardous driving conditions

29. Mudslides in on steep slopes destroy homes.

30. Strong winds of El Nino knock down trees

31. Ocean pier in S. California

32. Buoys from San Diego’s Scripp’s Institute are stationed in the Pacific Ocean to monitor water temperature and El Nino events

33. Density vs. Temperature It is the TEMP that is more important in stacking the layers of water Red (hot fresh) Clear (room temp fresh) Blue (cold salt) Yellow (warm salt)