ENSO nonlinearity in a warming climate

The El Nin˜o Southern Oscillation (ENSO) is known as the strongest natural inter-annual climate signal, having widespread consequences on the global weather, climate, ecology and even on societies. Understanding ENSO variations in a changing climate is therefore of primordial interest to both the climate community and policy makers. In this study, we focus on the change in ENSO nonlinearity due to climate change. We first analysed high statistical moments of observed Sea Surface Temperatures (SST) timeseries of the tropical Pacific based on the measurement of the tails of their Probability Density Function (PDF). This allows defining relevant metrics for the change in nonlinearity observed over the last century.