@article{fdi:010048466,
  title = {{B}iogeochemical impact of a model western iron source in the {P}acific {E}quatorial {U}ndercurrent},
  author = {{S}lemons, {L}. and {G}orgues, {T}. and {A}umont, {O}livier and {M}enk{\`e}s, {C}hristophe and {M}urray, {J}. {W}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}race element distributions in the source waters of the {P}acific {E}quatorial {U}ndercurrent ({EUC}) show the existence of elevated total acid-soluble iron concentrations. {T}his region has been suggested to contribute enough bioavailable iron to regulate interannual and interglacial variability in biological productivity downstream in the high-nitrate low-chlorophyll upwelling zone of the eastern equatorial {P}acific. {W}e investigated the advection and first-order biogeochemical impact of an imposed, data-based iron maximum in the western {P}acific {EUC} using an ecosystem model forced by a global dynamical model. {W}e imposed two source profiles of iron constrained by total acid-soluble iron measurements. {T}hough the data for total acid-soluble iron included both dissolved and acid-soluble particulate iron species, we treated all of the total acid-soluble iron as if it was dissolved and bioavailable. {A} deeper (270 m) source was centered in the density horizon of the observed iron maximum and a shallower (180 m) source was located in the core of our model's {EUC}, where a dissolved iron maximum has been frequently postulated. {T}hese source runs were compared with a control run that contained no specific source of iron associated with the {EUC}. {I}n the source runs elevated iron concentrations were simulated in the {EUC} across its entire zonal span, evident as a subsurface plume of dissolved iron slightly below the core of the {EUC}. {I}n the control run there was no iron maximum associated with the {EUC}. {U}pwelling of iron-replete water in the central and eastern equatorial {P}acific increased integrated primary productivity in the {W}yrtki box (180 degrees {W}:90 degrees {W}, 5 degrees {S}:5 degrees {N}, 0:200 m) by 41% and 66% for the deeper and shallower iron perturbation, respectively. {T}he source runs increased the realism of the zonal extent of {HNLC} conditions and the meridional distributions of biological productivity, relative to the control run. {H}owever, in the source simulations surface chlorophyll concentrations were too high by a factor of two and maximum surface nitrate concentrations were too low, relative to climatologies. {T}he relative abundance of diatoms roughly doubled upon the input of additional iron, exceeding field observations. {T}hough biogeochemical data are limited and we did not adjust parameters to optimize the model fits to observations, these results suggest that acid-soluble particulate iron supplied to the {EUC} in the western equatorial {P}acific is unlikely to be entirely bioavailable.},
  keywords = {{I}ron ; {E}cosystem model ; {B}ioavailability ; {E}quatorial {P}acific ; {L}imitation ; {H}igh-nitrate low-chlorophyll ; {T}ransport ; {E}xport ; {B}iological pump},
  booktitle = {},
  journal = {{D}eep-{S}ea {R}esearch {I} - {O}ceanographic {R}esearch {P}apers},
  volume = {56},
  numero = {12},
  pages = {2115--2128},
  ISSN = {0967-0637},
  year = {2009},
  DOI = {10.1016/j.dsr.2009.08.005},
  URL = {https://www.documentation.ird.fr/hor/fdi:010048466},
}