A Strong 2023/24 El Niño is Staged by Tropical Pacific Ocean Heat Content Buildup

Abstract

The upper ocean heat content in the equatorial Pacific usually serves as a primary precursor for an upcoming El Niño, while strong atmospheric perturbations such as westerly wind burst and easterly wind surge sometimes play a decisive role in determining the final intensity of the event. The tropical Pacific Ocean has just experienced a rare 3-year La Niña, which accumulated a huge amount of warm water in the western basin by the winter of 2022 with an intensity much stronger than those preceding the onset of strong El Niños in history. Using a state-of-the-art climate prediction system, here, we show that the restored warm water is sufficient for boosting a strong El Niño toward the end of 2023 and that an even stronger event could take place if a few sizable westerly wind bursts would occur in spring and early summer. This prediction is not sensitive to initial errors within the tropical Pacific but may be subject to some uncertainties brought about by influences from elsewhere.