@article{fdi:010068123,
  title = {{S}easonal variability of the oxygen minimum zone off {P}eru in a high-resolution regional coupled model},
  author = {{V}ergara, {O}. and {D}ewitte, {B}oris and {M}ontes, {I}. and {G}arcon, {V}. and {R}amos, {M}. and {P}aulmier, {A}ur{\'e}lien and {P}izarro, {O}.},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n addition to being one of the most productive upwelling systems, the oceanic region off {P}eru is embedded in one of the most extensive oxygen minimum zones ({OMZ}s) of the world ocean. {T}he dynamics of the {OMZ} off {P}eru remain uncertain, partly due to the scarcity of data and to the ubiquitous role of mesoscale activity on the circulation and biogeochemistry. {H}ere we use a high-resolution coupled physical/biogeochemical model simulation to investigate the seasonal variability of the {OMZ} off {P}eru. {T}he focus is on characterizing the seasonal cycle in dissolved {O}-2 ({DO}) eddy flux at the {OMZ} boundaries, including the coastal domain, viewed here as the eastern boundary of the {OMZ}, considering that the mean {DO} eddy flux in these zones has a significant contribution to the total {DO} flux. {T}he results indicate that the seasonal variations of the {OMZ} can be interpreted as resulting from the seasonal modulation of the mesoscale activity. {A}long the coast, despite the increased seasonal low {DO} water upwelling, the {DO} peaks homogeneously over the water column and within the {P}eru {U}ndercurrent ({PUC}) in austral winter, which results from mixing associated with the increase in both the intraseasonal wind variability and baro-clinic instability of the {PUC}. {T}he coastal ocean acts therefore as a source of {DO} in austral winter for the {OMZ} core, through eddy-induced offshore transport that is also shown to peak in austral winter. {I}n the open ocean, the {OMZ} can be divided vertically into two zones: an upper zone above 400 m, where the mean {DO} eddy flux is larger on average than the mean seasonal {DO} flux and varies seasonally, and a lower part, where the mean seasonal {DO} flux exhibits vertical-zonal propagating features that share similar characteristics than those of the energy flux associated with the annual extratropical {R}ossby waves. {A}t the {OMZ} meridional boundaries where the mean {DO} eddy flux is large, the {DO} eddy flux has also a marked seasonal cycle that peaks in austral winter (spring) at the northern (southern) boundary. {I}n the model, the amplitude of the seasonal cycle is 70% larger at the southern boundary than at the northern boundary. {O}ur results suggest the existence of distinct seasonal regimes for the ventilation of the {OMZ} by eddies at its boundaries. {I}mplications for understanding the {OMZ} variability at longer timescales are discussed.},
  keywords = {{PEROU}},
  booktitle = {},
  journal = {{B}iogeosciences},
  volume = {13},
  numero = {15},
  pages = {4389--4410},
  ISSN = {1726-4170},
  year = {2016},
  DOI = {10.5194/bg-13-4389-2016},
  URL = {https://www.documentation.ird.fr/hor/fdi:010068123},
}