Insights from low order model of increasing complexity: probability and temporal structure of climate extreme

This study provides insight to changes in the probability and temporal structure of mid-latitude circulation features under possible shift of average conditions to a more El Ni˜ no-like or La Ni˜ na-like state. I Analysis shows that the response to dierent El Ni˜no events in mid-latitudes is highly variable, depending on the corresponding changes to the combination of Equator-to-Pole Gradient and Ocean-Land Contrast. I Types of ENSO events and their potential impacts could be classified based on corresponding fF,Gg and the associated pdf’s of energy (X2 + Y2 + Z2), as well as the attractor’s properties. I The general impact of El Ni˜no conditions is dissipation and organization of the eddies via enhancement of the jet stream. I La Ni˜na conditions cannot be considered as the opposite of El Ni˜no conditions. Similar responses in mid-latitudes are possible. I The question whether ENSO information is transmitted to mid-latitudes via EPG or OLC changes, or both (ultimately seen as fF,Gg combinations) needs further investigation. I Seasonality eects on ENSO impact in mid-latitudes are important. I Many impacts identified in the present study are qualitatively consistent with high-order GCM results, thus illustrating the ability of low order models to represent atmospheric processes in a correct manner. I Hence, introducing low-frequency modes interactively in a plausible way may be useful in understanding the behavior and potential outcomes associated with low frequency forcings in the coupled ocean-atmosphere system.