Projected Changes in the Seasonal Cycle of Madden‐Julian Oscillation Precipitation and Wind Amplitude

Abstract

AbstractAlthough recent studies have examined the responses of annual‐ and seasonal‐mean Madden‐Julian oscillation (MJO) activity to global warming, little is known about the seasonal cycle changes that determine the timing of the peak MJO influence on local weather and climate. By analyzing the Community Earth System Model version 2 large ensemble at the end of the 21st century, we report changes in both the phase and amplitude of the seasonal cycle of MJO precipitation over the tropical Indian Ocean and southwestern Pacific. While the seasonal delay in phase of the MJO is related to the seasonal delay of total precipitation, with contributions from surface latent heat flux and circulation changes, the amplification in seasonal amplitude is consistent with the increase in MJO amplitude due to mean temperature increases. The shifts in phase of the seasonal cycle of the MJO under global warming may influence the predictability of extreme events.