@article{fdi:010053370,
  title = {{CO}2 maximum in the oxygen minimum zone ({OMZ})},
  author = {{P}aulmier, {A}ur{\'e}lien and {R}uiz-{P}ino, {D}. and {G}arcon, {V}.},
  editor = {},
  language = {{ENG}},
  abstract = {{O}xygen minimum zones ({OMZ}s), known as suboxic layers which are mainly localized in the {E}astern {B}oundary {U}pwelling {S}ystems, have been expanding since the 20th "high {CO}2" century, probably due to global warming. {OMZ}s are also known to significantly contribute to the oceanic production of {N}2{O}, a greenhouse gas ({GHG}) more efficient than {CO}2. {H}owever, the contribution of the {OMZ}s on the oceanic sources and sinks budget of {CO}2, the main {GHG}, still remains to be established. {W}e present here the dissolved inorganic carbon ({DIC}) structure, associated locally with the {C}hilean {OMZ} and globally with the main most intense {OMZ}s ({O}-2 < 20 mu mol kg(-1)) in the open ocean. {T}o achieve this, we examine simultaneous {DIC} and {O}-2 data collected off {C}hile during 4 cruises (2000-2002) and a monthly monitoring (2000-2001) in one of the shallowest {OMZ}s, along with international {DIC} and {O}-2 databases and climatology for other {OMZ}s. {H}igh {DIC} concentrations (>2225 mu mol kg(-1), up to 2350 mu mol kg-1) have been reported over the whole {OMZ} thickness, allowing the definition for all studied {OMZ}s a {C}arbon {M}aximum {Z}one ({CMZ}). {L}ocally off {C}hile, the shallow cores of the {OMZ} and {CMZ} are spatially and temporally collocated at 21 degrees {S}, 30 degrees {S} and 36 degrees {S} despite different cross-shore, long-shore and seasonal configurations. {G}lobally, the mean state of the main {OMZ}s also corresponds to the largest carbon reserves of the ocean in subsurface waters. {T}he {CMZ}s-{OMZ}s could then induce a positive feedback for the atmosphere during upwelling activity, as potential direct local sources of {CO}2. {T}he {CMZ} paradoxically presents a slight "carbon deficit" in its core (similar to 10%), meaning a {DIC} increase from the oxygenated ocean to the {OMZ} lower than the corresponding {O}-2 decrease (assuming classical {C}/{O} molar ratios). {T}his "carbon deficit" would be related to regional thermal mechanisms affecting faster {O}-2 than {DIC} (due to the carbonate buffer effect) and occurring upstream in warm waters (e. g., in the {E}quatorial {D}ivergence), where the {CMZOMZ} core originates. {T}he "carbon deficit" in the {CMZ} core would be mainly compensated locally at the oxycline, by a "carbon excess" induced by a specific remineralization. {I}ndeed, a possible co-existence of bacterial heterotrophic and autotrophic processes usually occurring at different depths could stimulate an intense aerobic-anaerobic remineralization, inducing the deviation of {C}/{O} molar ratios from the canonical {R}edfield ratios. {F}urther studies to confirm these results for all {OMZ}s are required to understand the {OMZ} effects on both climatic feedback mechanisms and marine ecosystem perturbations.},
  keywords = {},
  booktitle = {},
  journal = {{B}iogeosciences},
  volume = {8},
  numero = {2},
  pages = {239--252},
  ISSN = {1726-4170},
  year = {2011},
  DOI = {10.5194/bg-8-239-2011},
  URL = {https://www.documentation.ird.fr/hor/fdi:010053370},
}