Oceanic Nino Index

The US National Oceanic and Atmospheric Administration (NOAA) has predicted that the El Nino event will not take place due to the Oceanic Nino Index (ONI) moving into the neutral range.

Key Highlights

(i) ENSO is measured by two indices- 

1. Oceanic Niño Index: It is the primary indicator for monitoring the ocean part of El Niño-Southern Oscillation, or “ENSO”.

2. Southern Oscillation Index: The Oceanic Nino Index (ONI) and Southern Oscillation Index (SOI) are the primary indicators for monitoring the atmospheric part of ENSO.

(ii) The Oceanic Nino Index (ONI) tracks the 3-month average sea surface temperatures in the east-central tropical Pacific between 120°-170°W, near the International Dateline.

(iii) It also determines whether they are warmer or cooler than average.

 

About El Nino and La Nina

• El Nino and La Nina are opposing complex weather patterns resulting from variations in ocean temperatures in the Equatorial Pacific Region. It normally occurs for 9 to 12 months. 

• The ENSO cycle describes the variations in temperature between the ocean and atmosphere in the east-central Equatorial Pacific.

•  El Niño-Southern Oscillation (ENSO): El Nino and La Nina are together referred to as the El Niño-Southern Oscillation.