The pattern of El Niño has changed dramatically in recent years, according to the first seasonal record distinguishing different types of El Niño events over the last 400 years. A new category of El Niño has become far more prevalent in the last few decades than at any time in the past 4 centuries.

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The pattern of El Niño has changed dramatically in recent years, according to the first seasonal record distinguishing different types of El Niño events over the last 400 years. A new category of El Niño has become far more prevalent in the last few decades than at any time in the past 4 centuries.