@article{fdi:010086595,
  title = {{O}xygen variability during {ENSO} in the {T}ropical {S}outh {E}astern {P}acific},
  author = {{E}spinoza-{M}orriberón, {D}. and {E}chevin, {V}incent and {C}olas, {F}ran{\c{c}}ois and {T}am, {J}. and {G}utierrez, {D}. and {G}raco, {M}. and {L}edesma, {J}. and {Q}uispe-{C}calluari, {C}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {O}xygen {M}inimum {Z}one ({OMZ}) of the {T}ropical {S}outh {E}astern {P}acific ({TSEP}) is one of the most intensely deoxygenated water masses of the global ocean. {I}t is strongly affected at interannual time scales by {E}l {N}iño ({EN}) and {L}a {N}iña ({LN}) due to its proximity to the equatorial {P}acific. {I}n this work, the physical and biogeochemical processes associated with the subsurface oxygen variability during {EN} and {LN} in the period 1958-2008 were studied using a regional coupled physical-biogeochemical model and in situ observations. {T}he passage of intense remotely forced coastal trapped waves caused a strong deepening (shoaling) of the {OMZ} upper limit during {EN} ({LN}). {A} close correlation between the {OMZ} upper limit and thermocline depths was found close to the coast, highlighting the role of physical processes. {T}he subsurface waters over the shelf and slope off central {P}eru had different origins depending on {ENSO} conditions. {O}ffshore of the upwelling region (near 88°{W}), negative and positive oxygen subsurface anomalies were caused by {E}quatorial zonal circulation changes during {LN} and {EN}, respectively. {T}he altered properties were then transported to the shelf and slope (above 200 m) by the {P}eru-{C}hile undercurrent. {T}he source of nearshore oxygenated waters was located at 3°{S}-4°{S} during neutral periods, further north (1°{S}-1°{N}) during {EN} and further south (4°{S}-5°{S}) during {LN}. {T}he offshore deeper (< 200-300 m) {OMZ} was ventilated by waters originating from ~8°{S} during {EN} and {LN}. {E}nhanced mesoscale variability during {EN} also impacted {OMZ} ventilation through horizontal and vertical eddy fluxes. {T}he vertical eddy flux decreased due to the reduced vertical gradient of oxygen in the surface layer, whereas horizontal eddy fluxes injected more oxygen into the {OMZ} through its meridional boundaries. {I}n subsurface layers, remineralization of organic matter, the main biogeochemical sink of oxygen, was higher during {EN} than during {LN} due to oxygenation of the surface layer. {S}ensitivity experiments highlighted the larger impact of equatorial remote forcing with respect to local wind forcing during {EN} and {LN}.},
  keywords = {{PEROU} ; {PACIFIQUE} {SUD} {EST}},
  booktitle = {},
  journal = {{F}rontiers in {M}arine {S}cience},
  volume = {5},
  numero = {},
  pages = {526 [20 ]},
  ISSN = {2296-7745 },
  year = {2019},
  DOI = {10.3389/fmars.2018.00526},
  URL = {https://www.documentation.ird.fr/hor/fdi:010086595},
}