The Global Climate during El Niño and La Niña

Topics: Composite (average) climate | Seasonal extremes | How events differ


El Niño and La Niña can cause the "seasonal climate" -- the cumulative effects of the weather over a season -- to deviate from normal at many places around the globe. These pages analyze what happened during past El Niños and La Niñas and provide a guide to what may happen in the future.

Composite (average) climate

 o Average seasonal El Niño and La Niña climate means and anomalies new
Allows single or comparison plots of seasonal averaged variables in relation to El Niño and La Niña over the globe and the US.
 o Month by Month El Niño and La Niña composites
What does the seasonal cycle of different variables during an average (composite) El Niño and La Niña look like?
 o Global seasonal temperature and precipitation composites
Plot composite signals based on historical data of global surface temperature and precipitation. Includes animations.
 o Composite wintertime US temperature and precipitation means and anomalies
Posters show the El Niño/La Niña temperature and precipitation anomalies on one page. Postscript versions are available (2.8M) for the means and anomalies.


 o Plot climate anomalies and compare to El Niño's linear signal.
How do the precipitation and geopotential heights for a particular year/month compare to those one would expect from ENSO (assuming a linear ENSO effect)?

Seasonal extremes

 o Plot effects on seasonal climate extremes of temperature and precipitation over the United States ("Risk Plots")
Given an El Niño or La Niña condition, what are the odds of getting a warm versus a cold season? A wet versus a dry season?
 o Regional seasonal temperature and precipitation extremes with preceding and concurrent ENSO conditions.
Historical risk of seasonal temperature and precipitation extremes for specific regions of the United States. Risk is shown with the ENSO conditions preceding the seasonal value from 3 seasons to 0 seasons.
 o Posters
These "posters" show the comparison of actual climate throughout the year during a El Niño and La Niña event to those expected from a risk analysis of the historical climate record for the last 100 years. Surface temperature and precipitation are plotted. Note that these posters are large.

How events differ

 o Plots showing differences between the atmospheric response of El Niño and La Niña events.
Both differences in the tropical SST pattern and "random" variability of the the atmosphere mean that the climate of El Niño and La Niña events will not necessarily be the same from event to event.