PSL's El Niño FAQ
How will El Niño impact a particular region of the world?
What are the predictions for El Niño?
What is the SOI (Southern Oscillation Index)?
When is the MEI updated? How can I get those numbers?
Can I use PSL plots and how do I acknowledge PSL?
What is the most recent SST/El Niño data available?
What is a good source of El Niño information for young people?
What is source of El Niño/La Niña information for adults?
How do I get climate data to look at El Niño myself.
What years are El Niño/La Niña years.
What is the difference between El Niño, ENSO and the Southern Oscillation?
Who are good contacts for reporters?
Where can I find other ENSO FAQs?
How will El Niño impact a particular region?
- There has been a lot research investigating the effects of El Niño/Southern Oscillation on climate (temperature, rainfall, snowpack, climate extremes etc.) throughout the world. The research has been compiled at several web sites including
Note that there are very few regions where the effects of El Niño/La Nina are consistent every year due to both the varying nature of El Niño and the inherent variance of the
atmosphere/ocean system. The research is best utilized to indicate the probability of what the effects will be.
What are the predictions for El Niño?
- Official predictions for El Niño are produced by the Climate Prediction Center.
Unofficial forecasts based on different models and/or statistical techniques are also available at several locations.
When is the MEI updated? How can I get those numbers?
- The MEI is generally updated by the 3rd workday of the month. You can obtain the numerical values here. If you want further information about how the index is derived, please contact Klaus Wolter klaus.wolter@noaa.gov
Can I use PSL plots and how do I acknowledge PSL?
-
You can use any PSL generated plot (either from a pregenerated figure
or from an interactive program). We ask that you acknowledge the PSL in the publication. For example, "Image provided
by the NOAA/OAR/ESRL PSL, Boulder Colorado from
their Web site at http://psl.noaa.gov/".
What is the most recent SST/El Niño data?
- NOAA's PMEL maintains a list of the most recent data/plots available.
What is a good source of El Niño information for young people?
- See PSL's ENSO educational resource page.
What is source of information for adults?
- There are numerous webpages that have information about El Niño. Some of the more "complete" websites that have links to data, research, predictions and so forth are the NOAA El Niño portal,
the NOAA PMEL web page and the NOAA/CPC ENSO pages.
How do I get climate data to look at El Niño myself?
- PMEL maintains a list of El Niño related data sources. Other sources of data include the National Centers for Environmental Information (basic station data on daily and monthly time scales), the (National Snow and Ice Data Center), the National Geophysical Data Center, National Oceanographic Data Center, National Center for Atmospheric Research Data Inventory and the meteorological FAQ.
What years are El Niño/La Niña years?
- Definitions for what constitute an El Niño/La Niña event vary so
there is not a definitive set of years. However, PSL
(from Smith and Sardeshmukh
and Kiladas and Diaz),
CPC (ONI from the NOAA ERSST V4)
, and COAPS
maintain a list of years used in their research. In addition, PSL makes available the MEI and the extended MEI index and CPC has a
list of various atmospheric/ocean
indexes from 1950 that can be used to determine ENSO years. NASA has a precipitation based ENSO timeseries called the ESPI. Some ENSO timeseries are available from 1870 at PSL's GCOS Timeseries webpage and more at PSL including the MEI.
What is the SOI (Southern Oscillation Index)?
- It has been found that the cyclic warming and cooling of the eastern and central Pacific can be seen in the sea level pressure in the region. In particular, when the pressure measured at Darwin is compared with that measured at Tahiti, the differences between the two can be used to generate an "index" number. A positive number indicates La Niña (eastern tropical Pacific ocean cooling) and a negative number indicates El Niño (or ocean warming). Historical and recent values can be found at the Climate Prediction Center.
PSL has a historical perspective on the SOI.
What is the difference between El Niño, ENSO and the Southern Oscillation?
- El Niño refers to the oceanic component of the El Niño/Southern Oscillation system, the Southern Oscillation to the atmospheric component and ENSO to the coupled system. In practice, El Niño
is sometimes used to refer to the entire system. See the PSL historical perspective on the SOI.
Who are good contacts for reporters?
- The Office of Oceanic and Atmospheric Research has this media contact webpage which includes the ESRL contact.
Where can I find other ENSO FAQs?
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