1. SIO 210: ENSO conclusion Dec. 2, 2004 Interannual variability (end of this lecture + next) –Tropical Pacific: El Nino/Southern Oscillation –Southern Ocean imprint of ENSO –Tropical Atlantic: dipole mode This powerpoint was prepared for purposes of this lecture and course only. It contains graphics from copyrighted books and journals. Please do not use without acknowledgment of these sources.

2. ENSO: normal and La Nina conditions http://www.pmel.noaa.gov/tao/elnino/nino_normal.html

3. ENSO: El Nino conditions http://www.pmel.noaa.gov/tao/elnino/nino_normal.html

4. Map to show location of Tahiti and Darwin Tahiti Darwin Walker cell: low pressure at Darwin, high pressure at Tahiti Southern Oscillation Index: Tahiti SLP minus Darwin SLP

5. Southern Oscilllation index (NCEP) During El Nino: SOI is low: Tahiti minus Darwin is low, meaning that the pressure difference between them is reduced. Therefore the trade winds are weaker during ENSO. Note that Darwin and Tahiti anomalies are out of phase El Ninos: low SOI http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/bulletin/index.html

6. ENSO indices: based on SST. Most commonly used is the Nino3 or Nino3,4 http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/bulletin

7. SOI and 110°W temperature as of this week

8. SST imagery - today’s image

9. Normal conditions in the tropical Pacific

10. El Nino conditions in the tropical pacific

11. Tropical Pacific this week TAO Project Office PMEL/NOAA

12. Temperature - mean and anomalies along the equator November 2002: El NinoNovember 2004: weak El Nino

13. Time series: SST at equator El Nino La Nina

14. SST and zonal wind anomalies, equator

15. SST and dynamic height anomalies, equator

16. El Nino-La Nina surface height (NASA altimetry) http://topex-www.jpl.nasa.gov/science/el-nino.html

17. ENSO sea surface height anomaly http://www.osdpd.noaa.gov/

18. La Nina sea surface height anomaly http://www.osdpd.noaa.gov/

19. This month’s surface height (altimetry): El Nino is not developing strongly http://topex-www.jpl.nasa.gov/science/el-nino.html

20. Sea level pressure and anomalies NCEP October 2004

21. SST anomalies October 2004 NCEP

22. SST anomalies time series NCEP

23. ENSO - long time series of Nino3 index

24. Very long time series of ENSO: Kim Cobb et al. Based on corals.

25. Tool: Sea surface temperature pattern associated with El Nino/Southern Oscillation Correlation of SST record at each location with the Southern Oscillation Index

26. ENSO (SOI) SST and SLP patterns

27. SOI surface zonal wind and “clouds”

28. ENSO global precipitation effects

29. USA impacts of El Nino and La Nina: temperature

30. USA impacts of El Nino and La Nina: precipitation

31. Compare with SW US monsoon: monsoon is pretty much the same pattern as ENSO ENSO monsoon

32. El Nino - where are we right now? An El Nino event is building, and predictions of this winter’s conditions in N. America are related to it.

33. El Nino We are in a weak El Nino pattern now. NOAA Climate Prediction Center winter 2004-2005 patterns prediction: Figure 5. Seasonal U. S. temperature (left) and precipitation (right) outlooks for December 2004-February 2005. Outlooks prepared in mid-September 2004 reflect a blend of ENSO-related impacts and long-term trends. http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ warm dry cool wet

34. El Nino Great websites: http://www.pmel.noaa.gov/tao/elnino/nino-home.html http://topex-www.jpl.nasa.gov/science/el-nino.html