@article{fdi:010058478,
  title = {{I}mportance of the salinity barrier layer for the buildup of {E}l {N}ino},
  author = {{M}aes, {C}hristophe and {P}icaut, {J}o{\¨e}l and {B}elamari, {S}.},
  editor = {},
  language = {{ENG}},
  abstract = {{S}everal studies using sea level observations and coupled models have shown that heat buildup in the western equatorial {P}acific is a necessary condition for a major {E}l {N}ino to develop. {H}owever. none of these studies has considered the potential influence of the vertical salinity stratification on the heat buildup and thus on {E}l {N}ino. {I}n the warm pool, this stratification results in the presence of a barrier layer that controls the base of the ocean mixed layer. {A}nalyses of in situ and {TOPEX}/{P}oseidon data, associated with indirect estimates of the vertical salinity stratification, reveal the concomitant presence of heat buildup and a significant barrier layer in the western equatorial {P}acific. {T}his relationship occurs during periods of about one year prior to the mature phase of {E}l {N}ino events over the period 1993-2002. {A}nalyses from a coupled ocean-atmosphere general circulation model suggest that this relationship is statistically robust. {T}he ability of the coupled model to reproduce a realistic {E}l {N}ino together with heat buildup, westerly wind bursts, and a salinity barrier layer suggests further investigations of the nature of this relationship. {I}n order to remove the barrier layer, modifications to the vertical ocean mixing scheme are applied in the equatorial warm pool and during the 1-yr period of the heat buildup. {A}t the bottom of the ocean mixed layer, the heat buildup is locally attenuated, as expected from switching on the entrainment cooling. {A}t the surface, the coupled response over the warm pool increases the fetch of westerly winds and favors the displacement of the atmospheric deep convection toward the central equatorial {P}acific. {T}hese westerly winds generate a series of downwelling equatorial {K}elvin waves whose associated eastward currents drain the heat buildup toward the eastern {P}acific {O}cean. {T}he overall reduction of the heat buildup before the onset of {E}l {N}ino results in the failure of {E}l {N}ino. {T}hese coupled model analyses confirm that the buildup is a necessary condition for {E}l {N}ino development and show that the barrier layer in the western equatorial {P}acific is important for maintaining the heat buildup.},
  keywords = {{PACIFIQUE} ; {ZONE} {EQUATORIALE}},
  booktitle = {},
  journal = {{J}ournal of {C}limate},
  volume = {18},
  numero = {1},
  pages = {104--118},
  ISSN = {0894-8755},
  year = {2005},
  DOI = {10.1175/{JCLI}-3214.1},
  URL = {https://www.documentation.ird.fr/hor/fdi:010058478},
}