Efficiency of small scale carbon mitigation by patch iron fertilization
While nutrient depletion scenarios have long shown that the high-latitude High Nutrient Low Chlorophyll (HNLC) regions are the most effective for sequestering atmospheric carbon dioxide, recent simulations with prognostic biogeochemical models have suggested that only a fraction of the potential dra...
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ftdoajarticles:oai:doaj.org/article:fb35ef4299bf409ea9b3c4db94fb7bfd 2023-05-15T18:07:33+02:00 Efficiency of small scale carbon mitigation by patch iron fertilization J. L. Sarmiento R. D. Slater J. Dunne A. Gnanadesikan M. R. Hiscock 2010-11-01T00:00:00Z https://doi.org/10.5194/bg-7-3593-2010 https://doaj.org/article/fb35ef4299bf409ea9b3c4db94fb7bfd EN eng Copernicus Publications http://www.biogeosciences.net/7/3593/2010/bg-7-3593-2010.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 doi:10.5194/bg-7-3593-2010 1726-4170 1726-4189 https://doaj.org/article/fb35ef4299bf409ea9b3c4db94fb7bfd Biogeosciences, Vol 7, Iss 11, Pp 3593-3624 (2010) Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 article 2010 ftdoajarticles https://doi.org/10.5194/bg-7-3593-2010 2022-12-31T13:58:22Z While nutrient depletion scenarios have long shown that the high-latitude High Nutrient Low Chlorophyll (HNLC) regions are the most effective for sequestering atmospheric carbon dioxide, recent simulations with prognostic biogeochemical models have suggested that only a fraction of the potential drawdown can be realized. We use a global ocean biogeochemical general circulation model developed at GFDL and Princeton to examine this and related issues. We fertilize two patches in the North and Equatorial Pacific, and two additional patches in the Southern Ocean HNLC region north of the biogeochemical divide and in the Ross Sea south of the biogeochemical divide. We evaluate the simulations using observations from both artificial and natural iron fertilization experiments at nearby locations. We obtain by far the greatest response to iron fertilization at the Ross Sea site, where sea ice prevents escape of sequestered CO 2 during the wintertime, and the CO 2 removed from the surface ocean by the biological pump is carried into the deep ocean by the circulation. As a consequence, CO 2 remains sequestered on century time-scales and the efficiency of fertilization remains almost constant no matter how frequently iron is applied as long as it is confined to the growing season. The second most efficient site is in the Southern Ocean. The North Pacific site has lower initial nutrients and thus a lower efficiency. Fertilization of the Equatorial Pacific leads to an expansion of the suboxic zone and a striking increase in denitrification that causes a sharp reduction in overall surface biological export production and CO 2 uptake. The impacts on the oxygen distribution and surface biological export are less prominent at other sites, but nevertheless still a source of concern. The century time scale retention of iron in this model greatly increases the long-term biological response to iron addition as compared with simulations in which the added iron is rapidly scavenged from the ocean. Article in Journal/Newspaper Ross Sea Sea ice Southern Ocean Directory of Open Access Journals: DOAJ Articles Pacific Ross Sea Southern Ocean Biogeosciences 7 11 3593 3624 |
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collection |
Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
spellingShingle |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 J. L. Sarmiento R. D. Slater J. Dunne A. Gnanadesikan M. R. Hiscock Efficiency of small scale carbon mitigation by patch iron fertilization |
topic_facet |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
description |
While nutrient depletion scenarios have long shown that the high-latitude High Nutrient Low Chlorophyll (HNLC) regions are the most effective for sequestering atmospheric carbon dioxide, recent simulations with prognostic biogeochemical models have suggested that only a fraction of the potential drawdown can be realized. We use a global ocean biogeochemical general circulation model developed at GFDL and Princeton to examine this and related issues. We fertilize two patches in the North and Equatorial Pacific, and two additional patches in the Southern Ocean HNLC region north of the biogeochemical divide and in the Ross Sea south of the biogeochemical divide. We evaluate the simulations using observations from both artificial and natural iron fertilization experiments at nearby locations. We obtain by far the greatest response to iron fertilization at the Ross Sea site, where sea ice prevents escape of sequestered CO 2 during the wintertime, and the CO 2 removed from the surface ocean by the biological pump is carried into the deep ocean by the circulation. As a consequence, CO 2 remains sequestered on century time-scales and the efficiency of fertilization remains almost constant no matter how frequently iron is applied as long as it is confined to the growing season. The second most efficient site is in the Southern Ocean. The North Pacific site has lower initial nutrients and thus a lower efficiency. Fertilization of the Equatorial Pacific leads to an expansion of the suboxic zone and a striking increase in denitrification that causes a sharp reduction in overall surface biological export production and CO 2 uptake. The impacts on the oxygen distribution and surface biological export are less prominent at other sites, but nevertheless still a source of concern. The century time scale retention of iron in this model greatly increases the long-term biological response to iron addition as compared with simulations in which the added iron is rapidly scavenged from the ocean. |
format |
Article in Journal/Newspaper |
author |
J. L. Sarmiento R. D. Slater J. Dunne A. Gnanadesikan M. R. Hiscock |
author_facet |
J. L. Sarmiento R. D. Slater J. Dunne A. Gnanadesikan M. R. Hiscock |
author_sort |
J. L. Sarmiento |
title |
Efficiency of small scale carbon mitigation by patch iron fertilization |
title_short |
Efficiency of small scale carbon mitigation by patch iron fertilization |
title_full |
Efficiency of small scale carbon mitigation by patch iron fertilization |
title_fullStr |
Efficiency of small scale carbon mitigation by patch iron fertilization |
title_full_unstemmed |
Efficiency of small scale carbon mitigation by patch iron fertilization |
title_sort |
efficiency of small scale carbon mitigation by patch iron fertilization |
publisher |
Copernicus Publications |
publishDate |
2010 |
url |
https://doi.org/10.5194/bg-7-3593-2010 https://doaj.org/article/fb35ef4299bf409ea9b3c4db94fb7bfd |
geographic |
Pacific Ross Sea Southern Ocean |
geographic_facet |
Pacific Ross Sea Southern Ocean |
genre |
Ross Sea Sea ice Southern Ocean |
genre_facet |
Ross Sea Sea ice Southern Ocean |
op_source |
Biogeosciences, Vol 7, Iss 11, Pp 3593-3624 (2010) |
op_relation |
http://www.biogeosciences.net/7/3593/2010/bg-7-3593-2010.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 doi:10.5194/bg-7-3593-2010 1726-4170 1726-4189 https://doaj.org/article/fb35ef4299bf409ea9b3c4db94fb7bfd |
op_doi |
https://doi.org/10.5194/bg-7-3593-2010 |
container_title |
Biogeosciences |
container_volume |
7 |
container_issue |
11 |
container_start_page |
3593 |
op_container_end_page |
3624 |
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1766179752477982720 |