The El Nino Southern Oscillation (ENSO) is represented here by the Nino-3 and Nino3.4 sea surface temperature anomalies. The Nino-3 region is in the eastern equatorial Pacific bounded by the latitude 5S and 5N and the longtudes 150W and 90W. An anomalous increase of sea surface temperature indicates the onset of an el Nino event. The Nino-3.4 region is an area of the equatorial Pacific bounded by the latitudes 5S and 5N and the longitudes 170W and 120W. This is close to the region where sea surface temperature changes shift the pattern of regional rainfall.
The ENSO anomalies show the difference between ENSO SSTs and the average SST annual cyle.
|Nino-3 SST anomaly.|
Eastern equatorial pacific: 5N-5S x 150W-90W
|Nino-3.4 SST anomaly.|
Equatorial pacific: 5N-5S x 170W-120W