El Niño and La Niña affect the weather in large parts of the world. The effects depend strongly on the location and the season. We have studied the CRU TS 3.22 analyses of 2-meter temperature over land. As a measure of the strength of the relationship we used the correlation coefficient with the Niño3.4 index. The square of this number gives the fraction of the variance that is explained by this aspect of El Niño and La Niña.
In the temperature maps, red colours denote locations that on average are warmer during El Niño and cooler during La Niña. Blue colours are colder during El Niño and/or warmer during La Niña. Some North America effects are non-linear: the effect of La Niña is not the opposite of the effect of El Niño.