An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean
In this study we report diapycnal diffusive fluxes of dissolved iron (dFe), dissolved aluminium (dAl) and the major macronutrients to the surface waters of the North Atlantic subpolar gyre. Turbulent diffusivities at the base of the summer mixed layer ranged from 0.01 to 0.5 (median 0.07) cm2 s?1 an...
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ftsouthampton:oai:eprints.soton.ac.uk:360206 2023-08-27T04:09:48+02:00 An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean Painter, S.C. Henson, S.A. Forryan, A. Steigenberger, S. Klar, J. Stinchcombe, M.C. Rogan, N. Baker, A.R. Achterberg, E.P. Moore, C.M. 2014-04-16 https://eprints.soton.ac.uk/360206/ English eng Painter, S.C., Henson, S.A., Forryan, A., Steigenberger, S., Klar, J., Stinchcombe, M.C., Rogan, N., Baker, A.R., Achterberg, E.P. and Moore, C.M. (2014) An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean. Biogeosciences, 11 (8), 2113-2130. (doi:10.5194/bg-11-2113-2014 <http://dx.doi.org/10.5194/bg-11-2113-2014>). Article PeerReviewed 2014 ftsouthampton https://doi.org/10.5194/bg-11-2113-2014 2023-08-03T22:20:25Z In this study we report diapycnal diffusive fluxes of dissolved iron (dFe), dissolved aluminium (dAl) and the major macronutrients to the surface waters of the North Atlantic subpolar gyre. Turbulent diffusivities at the base of the summer mixed layer ranged from 0.01 to 0.5 (median 0.07) cm2 s?1 and daily macronutrient fluxes into the surface mixed layer typically represented < 0.5% of integrated mixed layer inventories, although fluxes were highly variable. Elevated nutrient fluxes of up to 4% of mixed layer inventories were identified on the Greenland Shelf, where integrated nutrient pools were lowest due to localised shoaling of the mixed layer. Diffusive fluxes of dFe and dAl were typically <0.1% of mixed layer inventories but were also highly variable between stations. Approximations of daily phytoplankton nutrient and Fe uptake indicate that the diffusive flux may at best represent <10% of phytoplankton macronutrient uptake, and only 1% of daily phytoplankton Fe uptake. The daily turbulent diffusive flux of dFe was comparable in magnitude to coincident estimates of aeolian Fe supply but despite shallower than normal convective mixing in winter 2010 the diffusive supply was 22 and 59 times smaller than the annual convective supply of Fe to the Irminger and Iceland basins respectively. The general picture obtained from this study is one of small magnitude diffusive nutrient and Fe fluxes to the subpolar North Atlantic during the period of annual nutrient minima and indicates that the diffusive supply mechanism is unlikely to alleviate the recently identified presence of seasonal iron limitation within the North Atlantic subpolar gyre; a condition exacerbated by low dFe:NO3? ratios in subsurface source waters. Article in Journal/Newspaper Greenland Iceland North Atlantic University of Southampton: e-Prints Soton Greenland Biogeosciences 11 8 2113 2130 |
institution |
Open Polar |
collection |
University of Southampton: e-Prints Soton |
op_collection_id |
ftsouthampton |
language |
English |
description |
In this study we report diapycnal diffusive fluxes of dissolved iron (dFe), dissolved aluminium (dAl) and the major macronutrients to the surface waters of the North Atlantic subpolar gyre. Turbulent diffusivities at the base of the summer mixed layer ranged from 0.01 to 0.5 (median 0.07) cm2 s?1 and daily macronutrient fluxes into the surface mixed layer typically represented < 0.5% of integrated mixed layer inventories, although fluxes were highly variable. Elevated nutrient fluxes of up to 4% of mixed layer inventories were identified on the Greenland Shelf, where integrated nutrient pools were lowest due to localised shoaling of the mixed layer. Diffusive fluxes of dFe and dAl were typically <0.1% of mixed layer inventories but were also highly variable between stations. Approximations of daily phytoplankton nutrient and Fe uptake indicate that the diffusive flux may at best represent <10% of phytoplankton macronutrient uptake, and only 1% of daily phytoplankton Fe uptake. The daily turbulent diffusive flux of dFe was comparable in magnitude to coincident estimates of aeolian Fe supply but despite shallower than normal convective mixing in winter 2010 the diffusive supply was 22 and 59 times smaller than the annual convective supply of Fe to the Irminger and Iceland basins respectively. The general picture obtained from this study is one of small magnitude diffusive nutrient and Fe fluxes to the subpolar North Atlantic during the period of annual nutrient minima and indicates that the diffusive supply mechanism is unlikely to alleviate the recently identified presence of seasonal iron limitation within the North Atlantic subpolar gyre; a condition exacerbated by low dFe:NO3? ratios in subsurface source waters. |
format |
Article in Journal/Newspaper |
author |
Painter, S.C. Henson, S.A. Forryan, A. Steigenberger, S. Klar, J. Stinchcombe, M.C. Rogan, N. Baker, A.R. Achterberg, E.P. Moore, C.M. |
spellingShingle |
Painter, S.C. Henson, S.A. Forryan, A. Steigenberger, S. Klar, J. Stinchcombe, M.C. Rogan, N. Baker, A.R. Achterberg, E.P. Moore, C.M. An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean |
author_facet |
Painter, S.C. Henson, S.A. Forryan, A. Steigenberger, S. Klar, J. Stinchcombe, M.C. Rogan, N. Baker, A.R. Achterberg, E.P. Moore, C.M. |
author_sort |
Painter, S.C. |
title |
An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean |
title_short |
An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean |
title_full |
An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean |
title_fullStr |
An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean |
title_full_unstemmed |
An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean |
title_sort |
assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar north atlantic ocean |
publishDate |
2014 |
url |
https://eprints.soton.ac.uk/360206/ |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Iceland North Atlantic |
genre_facet |
Greenland Iceland North Atlantic |
op_relation |
Painter, S.C., Henson, S.A., Forryan, A., Steigenberger, S., Klar, J., Stinchcombe, M.C., Rogan, N., Baker, A.R., Achterberg, E.P. and Moore, C.M. (2014) An assessment of the vertical diffusive flux of iron and other nutrients to the surface waters of the subpolar North Atlantic Ocean. Biogeosciences, 11 (8), 2113-2130. (doi:10.5194/bg-11-2113-2014 <http://dx.doi.org/10.5194/bg-11-2113-2014>). |
op_doi |
https://doi.org/10.5194/bg-11-2113-2014 |
container_title |
Biogeosciences |
container_volume |
11 |
container_issue |
8 |
container_start_page |
2113 |
op_container_end_page |
2130 |
_version_ |
1775351395198697472 |