1. 1 Trade Winds in Equatorial Pacific

2. 2 ITCZ Location July January ITCZ

3. 3 Equatorial Divergence vs Subtropical Convergence upwellingdownwelling

4. 4 Trade Winds Cause Variations in Sea Surface Height ITCZ SSH

5. 5 Meridional Trends in Trade Wind Strength, Sea Surface Height, and Currents in the Equatorial Pacific Trade Wind Speed Surface Current Direction SSH (cm) Depth (m) HPG westward eastward ITCZ I------Conv------IDivIConI-Div-I---Conv---I

6. 6 Zonal (E-W) Trend in Sea Surface Height Zonal (east-west) trend in Sea Surface Height Wind Stress SSH Temperature (+ = depth of EUC)

7. 7 Equatorial Undercurrent AAAA 6 EUC Velocity (m/s) Temperature (ºC) Velocity Cross Sections

8. 8 SST in Equatorial Pacific ºC

9. 9 Surface Nitrate Distribution

10. 10 Photosynthesis Rates in Surface Ocean

11. 11 Cross Sections in the Equatorial Pacific Temp Salinity Oxygen Phosphate Zonal Vel.

12. 12 Effect of El Nino on Anchovy Catch El Ninos in red

13. 13 Array of Buoys Monitored by NOAA for Wind Speed, SST, Salinity, Current Velocities The best instrumented region of the world’s ocean

14. 14 Sea Surface Temperature Changes

15. 15 Weakening of Trade Winds during El Nino Normal El Nino

16. 16 Atmospheric Circulation and Precipitation Changes during El Nino Normal El Nino

17. 17 SST and Chlorophyll during El Nino El Nino Normal 9

18. 18 Animation of SST Anomalies during El Nino of 1997 http://www.cdc.noaa.gov/map/clim/sst_olr/ old_sst/sst_9798_anim.shtmlhttp://www.cdc.noaa.gov/map/clim/sst_olr/ old_sst/sst_9798_anim.shtml

19. 19 History of Southern Oscillation Index (and correlation with El Nino events) ENSO Index

20. 20 Change in Zonal Atmospheric Circulation in Equatorial Pacific

21. 21 Global Weather Anomalies during El Nino

22. 22 Global Weather Anomalies during La Nino

23. 23 El Nino Effects on US Temperatures (Winter) Warmer in northern midwest and cooler in south

24. 24 El Nino Effects on US Precipitation (Winter) Wetter in southeast US

25. 25 El Nino Effects on Jet Stream position and US Weather

26. 26 Currently El Nino Conditions (Nov 2009) SST anomaly is currently 1-4ºC warmer than normal (avg.= 1.5ºC).