Different Impacts from Various El Niño Events on Wyrtki Jets in Boreal Autumn Season

The El Niño event is an air–sea interaction phenomenon over the tropical Pacific region, which is classified by canonical El Niño, El Niño Modoki I, and El Niño Modoki II based on the distinct temporal and spatial distributions of sea surface temperature anomalies. This research reveals that different types of El Niño events present distinct effects on the variation of Wyrtki jets over the equatorial Indian Ocean in boreal autumn season. The autumn Wyrtki jets of the Indian Ocean are significantly weaken during the canonical El Niño event. While, during the El Niño Modoki I and II events, the Wyrtki jets are stronger than climatology. Further analysis illustrates the anomalous Walker Circulations associated with different types of El Niño events are responsible for the variation of Wyrtki jets via the modulation of sea surface wind forcing over the Indo-Pacific region.