Modeling the global ocean iron cycle
MetadataShow full item record
We describe a model of the ocean transport and biogeochemical cycling of iron and the subsequent control on export production and macronutrient distributions. Ocean transport of phosphorus and iron are represented by a highly idealized six-box ocean model. Export production is parameterized simply; it is limited by light, phosphate, and iron availability in the surface ocean. We prescribe the regional variations in aeolian deposition of iron and examine three parameterizations of iron cycling in the deep ocean: (1) net scavenging onto particles, the simplest model; (2) scavenging and desorption of iron to and from particles, analogous to thorium; and (3) complexation. Provided that some unknown parameter values can be set appropriately, all three biogeochemical models are capable of reproducing the broad features of the iron distribution observed in the modern ocean and explicitly lead to regions of elevated surface phosphate, particularly in the Southern Ocean. We compare the sensitivity of Southern Ocean surface macronutrient concentration to increased aeolian dust supply for each parameterization. Both scavenging-based representations respond to increasing dust supply with a drawdown of surface phosphate in an almost linear relationship. The complexation parameterization, however, asymptotes toward a limited drawdown of phosphate under the assumption that ligand production does not respond to increased dust flux. In the scavenging based models, deep water iron concentrations and, therefore, upwelled iron continually increase with greater dust supply. In contrast, the availability of complexing ligand provides an upper limit for the deep water iron concentration in the latter model.
Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 18 (2004): GB1002, doi:10.1029/2003GB002061.
Suggested CitationArticle: Parekh, Payal, Follows, Michael J., Boyle, Edward A., "Modeling the global ocean iron cycle", Global Biogeochemical Cycles 18 (2004): GB1002, https://hdl.handle.net/1912/3390
Showing items related by title, author, creator and subject.
Cohesive and mixed sediment in the Regional Ocean Modeling System (ROMS v3.6) implemented in the Coupled Ocean–Atmosphere–Wave–Sediment Transport Modeling System (COAWST r1234) Sherwood, Christopher R.; Aretxabaleta, Alfredo L.; Harris, Courtney K.; Rinehimer, J. Paul; Verney, Romaric; Ferré, Bénédicte (Copernicus Publications on behalf of the European Geosciences Union, 2018-05-14)We describe and demonstrate algorithms for treating cohesive and mixed sediment that have been added to the Regional Ocean Modeling System (ROMS version 3.6), as implemented in the Coupled Ocean–Atmosphere–Wave–Sediment ...
Recent advances in Arctic ocean studies employing models from the Arctic Ocean Model Intercomparison Project Proshutinsky, Andrey; Aksenov, Yevgeny; Kinney, Jaclyn Clement; Gerdes, Rudiger; Golubeva, Elena; Holland, David; Holloway, Greg; Jahn, Alexandra; Johnson, Mark; Popova, Ekaterina E.; Steele, Michael; Watanabe, Eiji (Oceanography Society, 2011-09)Observational data show that the Arctic Ocean has significantly and rapidly changed over the last few decades, which is unprecedented in the observational record. Air and water temperatures have increased, sea ice volume ...
Air-sea CO2 fluxes and the controls on ocean surface pCO2 seasonal variability in the coastal and open-ocean southwestern Atlantic Ocean : a modeling study Arruda, R.; Calil, P. H. R.; Bianchi, A. A.; Doney, Scott C.; Gruber, Nicolas; Lima, Ivan D.; Turi, G. (Copernicus Publications on behalf of the European Geosciences Union, 2015-10-12)We use an eddy-resolving, regional ocean biogeochemical model to investigate the main variables and processes responsible for the climatological spatio-temporal variability of pCO2 and the air-sea CO2 fluxes in the ...