Concurrently with the continuous rise of atmospheric greenhouse gas concentrations, tropical Pacific sea-surface temperatures (SST) have increased significantly during the second half of the 20th century. Our observational analysis suggests that in this period the equatorial-Pacific intraseasonal surface-wind variability is significantly increased. In addition, its nonlinear interaction with the interannual El Niņo-Southern Oscillation (ENSO) have intensified substantially. These changes led to an increase in the El Niņo activity and the emergence of a new warm-pool El Niņo regime. State-of-the-art coupled general circulation models (CGCMs) simulate a future enhancement of the intraseasonal surface-wind variability in the equatorial Pacific in response to an atmospheric greenhouse gas increase, with potential repercussions for future El Niņo activity.