1. Section 2.3 Interannual Variability 
El Nino Southern Oscillation (ENSO)
(i) Observations
(ii) Theory for ENSO
(iii) Impacts
Interannual variability in Atlantic SSTs
The North Atlantic Oscillation (NAO)

2. Section 2.3.1 (ii) Theory of ENSO
The “Bjerknes Feedback”: A mechanism for growth of El Nino or La Nina

3. Fig.1 Schematic of Ekman Spiral in the Ocean

4. Fig.2 SSTs in Pacific in Dec

7. Fig.3 From S.-P. Xie (U Hawaii)

8. ENSO mechanism: the Bjerknes feedback
Fig.4

9. Bjerknes feedback - equatorial sections
El Niño
La Niña
atmos
ocean
longitude
longitude
Fig.5