1. El Niño and the Southern Oscillation (“ENSO”) A quick look

2. “Normal” SST
Walker circulation

3. ps(hPa)

4. Anomalous ps scaled by s.d.

5. Correlations (×10) of fluctuations in annual mean sea level pressure with those at Darwin. The magnitude of the correlation exceeds 0.4 in the shaded regions. (After Trenberth and Shea, 1987.)

8. “Normal” SST
Walker circulation

9. “Normal” SST

12. Sea surface temperature anomalies (C)
0 – 10S, 80 – 90W

13. SST anomalies (Nino 1+2) vs SOI

14. Annual rainfall (in percentiles) in a selection of regions
Annual rainfall (in percentiles) in a selection of regions. Black bars coincide with "El Niño" years.

16. cold
warm

20. cold
warm

21. Correlations (×10) of fluctuations in annual mean sea level pressure with those at Darwin. The magnitude of the correlation exceeds 0.4 in the shaded regions. (After Trenberth and Shea, 1987.)

22. El Nino impacts in U.S. winter

23. recent behavior in and over the equatorial Pacific

24. Current SST anomalies 2011 May 9