caa a22 4500 605473935 CHVBK 20210128100345.0 cr unu---uuuuu 210128e20150301xx s 000 0 eng 10.1007/s00382-014-2126-4 doi (NATIONALLICENCE)springer-10.1007/s00382-014-2126-4 The impact of westerly wind bursts and ocean initial state on the development, and diversity of El Niño events [Elektronische Daten] [Alexey Fedorov, Shineng Hu, Matthieu Lengaigne, Eric Guilyardi] Westerly wind bursts (WWBs) that occur in the western tropical Pacific are believed to play an important role in the development of El Niño events. Here, following the study of Lengaigne et al. (Clim Dyn 23(6):601-620, 2004), we conduct numerical simulations in which we reexamine the response of the climate system to an observed wind burst added to a coupled general circulation model. Two sets of twin ensemble experiments are conducted(each set has control and perturbed experiments). In the first set, the initial ocean heat content of the system is higher than the model climatology (recharged), while in the second set it is nearly normal (neutral). For the recharged state, in the absence of WWBs, a moderate El Niño with a maximum warming in the central Pacific (CP) develops in about a year. In contrast, for the neutral state, there develops a weak La Niña. However, when the WWB is imposed, the situation dramatically changes: the recharged state slides into an El Niño with a maximum warming in the eastern Pacific, while the neutral set produces a weak CP El Niño instead of previous La Niña conditions. The different response of the system to the exact same perturbations is controlled by the initial state of the ocean and the subsequent ocean-atmosphere interactions involving the interplay between the eastward shift of the warm pool and the warming of the eastern equatorial Pacific. Consequently, the observed diversity of El Niño, including the occurrence of extreme events, may depend on stochastic atmospheric processes, modulating El Niño properties within a broad continuum. Springer-Verlag Berlin Heidelberg, 2014 El Niño dynamics nationallicence El Niño flavors nationallicence Westerly wind bursts (WWB) nationallicence Climate models nationallicence Fedorov Alexey Department of Geology and Geophysics, Yale University, 06511, New Haven, CT, USA aut Hu Shineng Department of Geology and Geophysics, Yale University, 06511, New Haven, CT, USA aut Lengaigne Matthieu IPSL/LOCEAN, Sorbonne Universités (UPMC-Paris 6, CNRS, IRD, MNHN), Paris, France aut Guilyardi Eric IPSL/LOCEAN, Sorbonne Universités (UPMC-Paris 6, CNRS, IRD, MNHN), Paris, France aut Climate Dynamics Springer Berlin Heidelberg 44/5-6(2015-03-01), 1381-1401 0930-7575 44:5-6<1381 2015 44 382 https://doi.org/10.1007/s00382-014-2126-4 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00382-014-2126-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Fedorov Alexey Department of Geology and Geophysics, Yale University, 06511, New Haven, CT, USA aut NATIONALLICENCE 700 1- Hu Shineng Department of Geology and Geophysics, Yale University, 06511, New Haven, CT, USA aut NATIONALLICENCE 700 1- Lengaigne Matthieu IPSL/LOCEAN, Sorbonne Universités (UPMC-Paris 6, CNRS, IRD, MNHN), Paris, France aut NATIONALLICENCE 700 1- Guilyardi Eric IPSL/LOCEAN, Sorbonne Universités (UPMC-Paris 6, CNRS, IRD, MNHN), Paris, France aut NATIONALLICENCE 773 0- Climate Dynamics Springer Berlin Heidelberg 44/5-6(2015-03-01), 1381-1401 0930-7575 44:5-6<1381 2015 44 382