1. Material for Exam 2 starts HERE

2. Oceanic Currents Surface Currents –Cold = high latitude –Warm = low latitude –Gyres: circulate in which directions?

3. Major Ocean Currents Figure 6.22 Peru Current

4. Oceanic Currents Deep Currents –Thermohaline circulation –Distributes energy –Effects of global warming?

5. Deep Currents Figure 6.23

6. ENSO events ENSO events are a disruption of the ocean-atmosphere system in the tropical Pacific El Nino Southern Oscillation –El Nino – ocean –Southern Oscillation – atmosphere

7. El Niño Changes in pressure patterns Changes in wind patterns Mainly concentrated in the Pacific Ocean Measured using Southern Oscillation Index –Differences in pressure observed in Tahiti and Darwin, Australia –Combined to form ENSO Affects weather globally

8. Buoys

9. El Niño

10. Impacts of ENSO Events Marine environments Atlantic hurricanes Global precipitation patterns Wildfires

11. Australia-Drought and bush fires Indonesia, Philippines-Crops fail, starvation follows India, Sri Lanka-Drought,fresh water shortages Tahiti-6 tropical cyclones South America-Fish industry devastated Across the Pacific-Coral reefs die Colorado River basin-Flooding, mud slides Gulf states-Downpours cause death, property damage Peru, Ecuador-Floods, landslides Southern Africa-Drought, disease, malnutrition

12. El Niño

13. ENSO When high and low pressure systems exist in some locations, they not only impact local weather conditions, but also influence the overall size, shape, and position of the entire Rossby wave pattern Teleconnections: relationship between weather or climate patterns at two widely separated locations

14. ENSO

15. Occurs once every 3 to 5 years (but varies) Is regulated by PDO – Switch to PDO warm phase in 1999 appears to have dampened ENSO Major ENSO events in last 25 years: 1982–1983, 1986–1987, 1991–1993, 1997–1998, 2002–2003 1997–1998 was so intense, it disrupted global weather

16. Normal

17. Normal Year

18. ENSO

20. ENSO Year

21. La Nina El Niño = warm phase, La Niña = cool phase La Niña brings extreme normal conditions Not all El Niño events are followed by La Niña events La Niña events increase wildfires in the SE and Atlantic hurricanes

22. La Nina