ENSO Teleconnections Modulated by the State of the Equatorial Atlantic and Indian Oceans

Abstract Equatorial sea surface temperature anomalies have profound impacts on tropical and extra-tropical sub-seasonal and seasonal weather variability. While extensive research explored the impacts of El Niño-Southern Oscillation (ENSO) and its diversity on the global teleconnections, the weakness of ENSO-attributed signals over Europe, Africa and the Middle East has remained a challenge. In this study, ENSO teleconnection modulation is defined by considering the concurrent state of the equatorial Atlantic and Indian Oceans to investigate their impacts on modulating tropical and extra-tropical teleconnections. The results show that ENSO teleconnection patterns are influenced by the anomalous state of the two other basins, in some cases even leading to out-of-phase circulation anomalies. The impacts are highlighted for circulation, temperature, and precipitation anomalies in all seasons, aiming to understand the modulation of ENSO teleconnections by other equatorial oceanic basins, ultimately facilitating sub-seasonal and seasonal weather forecast skill.