Suppressive MJO in April 2014 Downgraded the 2014/15 El Niño

• DOI: 10.1175/jcli-d-23-0449.1
• Publication Date: 2024-03-26T11:27:17Z
• Authors: Jie Wang; Dake Chen; Tao Lian; Baosheng Li; Xiang Han; Ting Liu
• Keywords: Madden–Julian oscillation

Abstract The sudden halting of the extreme 2014/15 El Niño expected by many was attributed to absence westerly wind bursts (WWBs) in late spring and early summer 2014 previous works, yet cause lack WWBs overlooked. Using ERA5 reanalysis IBTrACS dataset, as well a set coupled model experiments, we showed that May efficiently downgraded intensity from moderate weak event closely associated with strong suppressive MJO originating central tropical Indian Ocean mid-April 2014. underwent two pathways once passing through Maritime Continent May. Along eastward pathway, prevailed over western–central equatorial Pacific, directly prohibiting occurrence at equator via inducing easterly anomaly. northeastward downward motions relative dry air vertical zonal shear suppressed activity cyclones northwestern another source WWBs. Our results indicate contributions development both direct indirect ways should be taken into account for improving prediction.