El Niño/Southern Oscillation (ENSO) is the variance of the climate caused by the interaction between the ocean and atmosphere in the equatorial belt. The equatorial is position of associate relationship in sea surface temperature anomalies.The mass of warm water moving along the equatorial Pacific Sovereign area leads to two South American coast.
Thus, it found an indicator of ENSO.
The indicators used to measure the anomaly of the ENSO has several , such as Oceanic Nino Index (ONI), Multivariate ENSO Index (MEI), Japan Meteorological Agency Sea Surface Temperature Index (JMA SST Index) , The Southern Oscillation Index (SOI), and Outgoing Long Wave Radiation (OLR) etc.
The details are shown in Table 2.2.