Tropical North Atlantic as a potential non-stationary modulator of ENSO-European rainfall teleconnection

• Main Authors: López-Parages, Jorge, Martín-Rey, Marta, Losada, Teresa, Polo, Irene, Rodríguez-Fonseca, Belén, Terray, Laurent
• Format: Conference Object
• Language: English
• Published: European Geosciences Union 2019
• Subjects: North Atlantic
• Online Access: http://hdl.handle.net/10261/241069

European Geosciences Union (EGU) General Assembly, 7-12 April 2019, Vienna, Austria.-- 1 page El Niño-Southern Oscillation (ENSO) impact on the North Atlantic European sector (NAE) still rises many unan-swered questions. Nowadays, there is a growing evidence advocating for a non-stationary feature affecting both,the tropospheric and the stratospheric pathways, of the ENSO-NAE teleconnection. In particular, a changing linkbetween ENSO and the spring Euro-Mediterranean rainfall has been documented in response to different phasesof the Atlantic Multidecadal Oscillation (AMO). Nevertheless, the underlying physical explanations are far to becompletely understood. In this study a purely tropospheric mechanism, in which the Tropical North Atlantic (TNA)plays a major role, is presented. Our results rely on the distinct capacity of ENSO to generate a zonal SST gradientover the TNA under different AMO phases. Consequently, an atmospheric response, also related to ENSO, canbe triggered from the TNA to the European sector. The occurrence of this ENSO-NAE teleconnection via TNAcould be subject to inter-decadal changes of ENSO properties and Atlantic background conditions. In this studythis issue is analyzed in 1) observations, and 2) low-resolution and high-resolution atmospheric and coupled GCMsimulations. It is expected that the novel proposed mechanism gives a step forward in the understanding of the roleof the Atlantic basin as modulator of the ENSO-NAE teleconnection Peer reviewed