The impact of the processes in the Southern Ocean on ENSO development

Abstract

The paper presents the review of the model study of the role of the Southern Ocean in the processes of interaction of the ocean-atmosphere system at short time scales impacting the El Nino–Southern Oscillation (ENSO). It is shown that the variability of wind and atmospheric pressure over the Antarctic Circumpolar Current (ACC), together with the effects of the topography and coastline, significantly impact the development of ENSO events. A new paradigm for ENSO is proposed that allows explaining the current weakening of the interrelation between the variability in wind and water volume in the tropical warm pool in the western equatorial Pacific and the onset of ENSO. The weakness of the interrelationship between ENSO and variability in the equatorial warm water volume of the equatorial Pacific, together with wind variability in the western equatorial Pacific, can be explained by the fact that the process occurred in the Southern Ocean recently became a major contributor amplifying ENSO events. The reproduction in numerical models of ocean dynamics for the mechanism found can improve the accuracy of the forecast of El Nino events.