Salient difference of sea surface temperature over the North Atlantic in the spring following three super El Niño events

• Published in: Environmental Research Letters
• Main Authors: Yu, Jinhua, Zhang, Xuyu, Li, Laurent, Shi, Chunhua, Ye, Yangbo
• Other Authors: Key Laboratory of Meteorological Disaster Nanjing University (KLME - NUIST), Nanjing University of Information Science and Technology (NUIST), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: North Atlantic SSTA; super El Niño events; teleconnection; [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; North Atlantic; North Atlantic oscillation
• Online Access: https://hal.sorbonne-universite.fr/hal-02942019; https://hal.sorbonne-universite.fr/hal-02942019/document; https://hal.sorbonne-universite.fr/hal-02942019/file/Yu_2020_Environ._Res._Lett._15_094040.pdf; https://doi.org/10.1088/1748-9326/aba20a

International audience Despite similar evolution of Niño3.4 index for three strong El Niño events in the tropical Pacific in 1982–1983, 1997–1998 and 2015–2016, divergent sea surface temperature anomalies (SSTAs) were observed in the North Atlantic (NA) in spring following El Niño peak. Strong teleconnection occurred for the first two events in 1982–1983 and 1997–1998, leading to a negative phase of a North Atlantic Oscillation-like circulation over the extratropical NA, and thus a positive tripolar SSTA pattern in the NA. But the teleconnection was weak for the case of 2015–2016 El Niño, the SSTA in spring 2016 in NA being mainly created and maintained by the preconditioning of the NA basin and local atmosphere-ocean interactions. The salient difference among the three events resides in their ways to operate the teleconnection linking the central-eastern equatorial Pacific and the subtropical eastern North Pacific to the extratropical NA, which would be a key to explain the different impacts of the three exceptional El Niño events. It is furthermore shown that the reduced anomalous westerlies over Central America along 30° N around the peak time of 2015–2016 El Niño play a role of inhibition for an efficient Rossby wave energy propagation from the tropics, eastward into the Gulf of Mexico and northward into midlatitudes in the western NA.