Increased occurrences of consecutive La Niña events under global warming

Abstract Most El Niño events occur sporadically and peak in a single winter 1–3 , whereas La Niña tends to develop after an El Niño and last for two years or longer 4–7 . Relative to single-year La Niña, consecutive La Niña features meridionally broader easterly winds and hence a slower heat recharge of the equatorial Pacific 6,7 , enabling the cold anomalies to persist, exerting prolonged impacts on global climate, ecosystems and agriculture 8–13 . Future changes to multi-year-long La Niña events remain unknown. Here, using climate models under future greenhouse-gas forcings 14 , we find an increased frequency of consecutive La Niña ranging from 19 ± 11% in a low-emission scenario to 33 ± 13% in a…