@article{fdi:010055952,
  title = {{V}ertical structure variability and equatorial waves during central {P}acific and eastern {P}acific {E}l {N}ios in a coupled general circulation model},
  author = {{D}ewitte, {B}oris and {C}hoi, {J}. and {A}n, {S}. {I}. and {T}hual, {S}.},
  editor = {},
  language = {{ENG}},
  abstract = {{R}ecent studies report that two types of {E}l {N}io events have been observed. {O}ne is the cold tongue {E}l {N}io or {E}astern {P}acific {E}l {N}io ({EP} {E}l {N}io), which is characterized by relatively large sea surface temperature ({SST}) anomalies in the eastern {P}acific, and the other is the warm pool {E}l {N}io (a.k.a. '{C}entral {P}acific {E}l {N}io' ({CP} {E}l {N}io) or '{E}l {N}io {M}odoki'), in which {SST} anomalies are confined to the central {P}acific. {H}ere the vertical structure variability of the periods during {EP} and {CP} is investigated based on the {GFDL}_{CM}2.1 model in order to explain the difference in equatorial wave dynamics and associated negative feedback mechanisms. {I}t is shown that the mean stratification in the vicinity of the thermocline of the central {P}acific is reduced during {CP} {E}l {N}io, which favours the contribution of the gravest baroclinic mode relatively to the higher-order slower baroclinic mode. {E}nergetic {K}elvin and first-meridional {R}ossby wave are evidenced during the {CP} {E}l {N}io with distinctive amplitude and propagating characteristics according to their vertical structure (mostly first and second baroclinic modes). {I}n particular, the first baroclinic mode during {CP} {E}l {N}io is associated to the ocean basin mode and participates to the recharge process during the whole {E}l {N}io cycle, whereas the second baroclinic mode is mostly driving the discharge process through the delayed oscillator mechanism. {T}his may explain that the phase transition from warm to neutral/cold conditions during the {CP} {E}l {N}io is delayed and/or disrupted compared to the {EP} {E}l {N}io. {O}ur results have implications for the interpretation of the variability during periods of high {CP} {E}l {N}io occurrence like the last decade.},
  keywords = {},
  booktitle = {},
  journal = {{C}limate {D}ynamics},
  volume = {38},
  numero = {11-12},
  pages = {2275--2289},
  ISSN = {0930-7575},
  year = {2012},
  DOI = {10.1007/s00382-011-1215-x},
  URL = {https://www.documentation.ird.fr/hor/fdi:010055952},
}