We are grateful to Annalisa Cherchi and Silvio Gualdi for discussions on the ENSO phenomenon, its teleconnections, and modeling; and to Antonio Navarra for the discussion and careful reading of the manuscript and for suggesting improvements. We also would like to thank Sarah Ineson, Paul Kushner, Judith Perlwitz, and Adam Scaife for discussions during the preparation of this work, and three anonymous reviewers for their constructive comments, which have helped to improve this manuscript. We acknowledge the ECMWF, Special Project on Middle Atmosphere Modelling, for providing computing time for the new set of simulations presented here. Part of this work was supported by the SCOUT-O3 Integrated Project (Contract 505390) of the European Commission. Chiara Cagnazzo was supported by the Centro Euro-Mediterraneo per i Cambiamenti Climatici.
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