Publications des scientifiques de l'IRD

Person R., Aumont Olivier, Madec G., Vancoppenolle M., Bopp L., Merino N. (2019). Sensitivity of ocean biogeochemistry to the iron supply from the Antarctic Ice Sheet explored with a biogeochemical model. Biogeosciences, 16 (18), p. 3583-3603. ISSN 1726-4170.

Titre du document
Sensitivity of ocean biogeochemistry to the iron supply from the Antarctic Ice Sheet explored with a biogeochemical model
Année de publication
2019
Type de document
Article référencé dans le Web of Science WOS:000487996500001
Auteurs
Person R., Aumont Olivier, Madec G., Vancoppenolle M., Bopp L., Merino N.
Source
Biogeosciences, 2019, 16 (18), p. 3583-3603 ISSN 1726-4170
Iron (Fe) delivery by the Antarctic Ice Sheet (AIS) through ice shelf and iceberg melting enhances primary productivity in the largely iron-limited Southern Ocean (SO). To explore this fertilization capacity, we implement a simple representation of the AIS iron source in the global ocean biogeochemical model NEMO-PISCES. We evaluate the response of Fe, surface chlorophyll, primary production, and carbon (C) export to the magnitude and hypothesized vertical distributions of the AIS Fe fluxes. Surface Fe and chlorophyll concentrations are increased up to 24% and 12 %, respectively, over the whole SO. The AIS Fe delivery is found to have a relatively modest impact on SO primary production and C export, which are increased by 0.063 +/- 0.036 PgC yr(-1) and 0.028 +/- 0.016, respectively. However, in highly fertilized areas, primary production and C export can be increased by up to 30% and 42 %, respectively. Icebergs are predicted to have a much larger impact on Fe, surface chlorophyll, and primary productivity than ice shelves in the SO. The response of surface Fe and chlorophyll is maximum in the Atlantic sector, northeast of the tip of the Antarctic Peninsula, and along the East Antarctic coast. The iceberg Fe delivery below the mixed layer may, depending on its assumed vertical distribution, fuel a non-negligible subsurface reservoir of Fe. The AIS Fe supply is effective all year round. The seasonal variations of the iceberg Fe fluxes have regional impacts that are small for annual mean primary productivity and C export at the scale of the SO.
Plan de classement
Limnologie physique / Océanographie physique [032] ; Ecologie, systèmes aquatiques [036]
Description Géographique
OCEAN INDIEN ; PACIFIQUE ; ATLANTIQUE
Localisation
Fonds IRD [F B010077036]
Identifiant IRD
fdi:010077036
Contact