NINO3. 4 index is defined as the average of SST anomalies over the region 5°N – 5°S and 170° – 120°W. NCC classifies the NINO3. 4 temperature anomaly as “warm” if it exceeds 0.8°C, which is about one standard deviation above average.
What is El Niño 3.4 index?
The Niño 3.4 index typically uses a 5-month running mean, and El Niño or La Niña events are defined when the Niño 3.4 SSTs exceed +/- 0.4C for a period of six months or more.
How do you calculate El Niño?
There are three main ways to measure an El Niño event:
- By measuring trade winds.
- By measuring pressure and calculating the Southern Oscillation Index (SOI).
- By measuring sea surface temperature using the TAO array and calculating an index.
Where is the Nino 3.4 region?
eastern equatorial Pacific
The Nino-3 region spans the eastern equatorial Pacific between 5N-5S, 150W-90W. The Nno 3.4 region spans the east-central equatorial Pacific between 5N-5S, 170W-120W.
What is ENSO Upsc?
The ENSO is a recurring climatic pattern involving temperature changes in the waters of the eastern and central tropical Pacific Ocean, and changes in the patterns of upper and lower-level winds, sea level pressure, and tropical rainfall across the Pacific Basin.
Is Soi positive during El Niño?
During El Niño, the SOI is negative, and the anomalies are reversed.
Who named La Nina?
Niña
| History | |
|---|---|
| Spain | |
| Name | Santa Clara |
| Namesake | Saint Clare |
| Owner | Juan Niño |
What is the equatorial Pacific?
The equatorial Pacific is an exception. This reversal drives warm surface water from the western Pacific eastward, leading to the development of unusually warm sea surface temperatures east of the international dateline. The lessened winds also bring less CO2-enriched water to the surface.
What is the Nino 3 4 index?
The NINO3.4 index is one of several El Niño/Southern Oscillation (ENSO) indicators based on sea surface temperatures. NINO3.4 is the average sea surface temperature anomaly in the region bounded by 5°N to 5°S, from 170°W to 120°W.
Where can I find the niniño ENSO index?
Niño 3.4 Sea Surface Temperature (SST) ENSO index (monthly time series: 1982-2017) is obtained from the NOAA National Center for Climate Prediction online archives.
What are the different Nino SST indices?
Nino SST Indices (Nino 1+2, 3, 3.4, 4; ONI and TNI) Niño 1+2 (0-10S, 90W-80W): The Niño 1+2 region is the smallest and eastern-most of the Niño SST regions, and corresponds with the region of coastal South America where El Niño was first recognized by the local populations. This index tends to have the largest variance of the Niño SST indices.
How are El Niño and La Niña anomalies calculated?
Usually the anomalies are computed relative to a base period of 30 years. The Niño 3.4 index and the Oceanic Niño Index (ONI) are the most commonly used indices to define El Niño and La Niña events. Other indices are used to help characterize the unique nature of each event.
