1. 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. Thor Heyerdahl and crew of 5 Sailed across the South Pacific from South America in a handcrafted raft called the Kon-Tiki in 1947 and landed in Polynesia Demonstrated it is possible to travel across the ocean using ocean currents and wind Believed people from Peru rafted 3000 miles across the Pacific Ocean and settled the islands of Polynesia

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 http://topex-www.jpl.nasa.gov/overview/climate-water.html

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 a b c d

10. Coriolis Effect Demonstration: Southern Hemisphere Draw 2 circles Rotate the paper clockwise Prediction: Draw a straight line from a to b. Describe the result Draw a straight line from c to d. Describe the result c d a b

11. Continents cause surface currents to change directions

12. 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

13. 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

14. 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

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

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

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

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

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

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

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

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

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

24. Accidents and injuries are greater with stormy weather

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

26. Saturated hills slide, creating hazardous driving conditions

27. Mudslides in on steep slopes destroy homes.

28. Strong winds of El Nino knock down trees

29. Ocean pier in S. California

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

31. El Nino will be back

32. What do you know? A supertanker breaks apart off the coast of Japan. Millions of gallons of crude oil spill into the ocean. Prepare a news broadcast detailing how San Diego’s beaches could be affected. Draw a map and use your notes to explain your answer. San Diego