Distinct Onset Mechanisms of Two Subtypes of CP El Niño and Their Changes in Future Warming

This study analyzes two subtypes of Central Pacific (CP) El Niño and shows that they possess different sea surface temperature evolution patterns in the Indo-Pacific Oceans, distinct generation mechanisms, can respond differently to global warming. The CP-I type is triggered tropical western by weaker-than-normal Australian winter monsoon (AM) through a subsurface thermocline mechanism accompanied significant Indian Ocean CP-II onsets subtropical North Meridional Mode (PMM) coupling weak warming anomalies Ocean. Two climate models projections indicate may occur more frequently than future due changes PMM AM activities, which should weaken influences on result events onset from American coast.