Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls
The remineralization depth of particulate organic carbon (POC) fluxes exported from the surface ocean exerts a major control over atmospheric CO₂ levels. According to a long-held paradigm most of the POC exported to depth is associated with large particles. However, recent lines of evidence suggest...
Published in: | Global Biogeochemical Cycles |
---|---|
Main Authors: | , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Amer Geophysical Union
2017
|
Subjects: | |
Online Access: | https://eprints.utas.edu.au/45154/ https://eprints.utas.edu.au/45154/2/RODA124346.pdf |
id |
ftunivtasmania:oai:eprints.utas.edu.au:45154 |
---|---|
record_format |
openpolar |
spelling |
ftunivtasmania:oai:eprints.utas.edu.au:45154 2023-05-15T18:25:00+02:00 Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls Baker, CA Henson, SA Cavan, EL Giering, SLC Yool, A Gehlen, M Belcher, A Riley, JS Smith, HEK Sanders, R 2017 application/pdf https://eprints.utas.edu.au/45154/ https://eprints.utas.edu.au/45154/2/RODA124346.pdf en eng Amer Geophysical Union https://eprints.utas.edu.au/45154/2/RODA124346.pdf Baker, CA, Henson, SA, Cavan, EL orcid:0000-0003-1099-6705 , Giering, SLC, Yool, A, Gehlen, M, Belcher, A, Riley, JS, Smith, HEK and Sanders, R 2017 , 'Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls' , Global Biogeochemical Cycles, vol. 31, no. 7 , pp. 1051-1065 , doi:10.1002/2017GB005638 <http://dx.doi.org/10.1002/2017GB005638>. carbon cycle oceans Article PeerReviewed 2017 ftunivtasmania https://doi.org/10.1002/2017GB005638 2022-03-07T23:17:12Z The remineralization depth of particulate organic carbon (POC) fluxes exported from the surface ocean exerts a major control over atmospheric CO₂ levels. According to a long-held paradigm most of the POC exported to depth is associated with large particles. However, recent lines of evidence suggest that slow-sinking POC (SSPOC) may be an important contributor to this flux. Here we assess the circumstances under which this occurs. Our study uses samples collected using the Marine Snow Catcher throughout the Atlantic Ocean, from high latitudes to midlatitudes. We find median SSPOC concentrations of 5.5 μg L−1, 13 times smaller than suspended POC concentrations and 75 times higher than median fast-sinking POC (FSPOC) concentrations (0.07 μg L−1). Export fluxes of SSPOC generally exceed FSPOC flux, with the exception being during a spring bloom sampled in the Southern Ocean. In the Southern Ocean SSPOC fluxes often increase with depth relative to FSPOC flux, likely due to midwater fragmentation of FSPOC, a process which may contribute to shallow mineralization of POC and hence to reduced carbon storage. Biogeochemical models do not generally reproduce this behavior, meaning that they likely overestimate long-term ocean carbon storage. Article in Journal/Newspaper Southern Ocean University of Tasmania: UTas ePrints Southern Ocean Global Biogeochemical Cycles 31 7 1051 1065 |
institution |
Open Polar |
collection |
University of Tasmania: UTas ePrints |
op_collection_id |
ftunivtasmania |
language |
English |
topic |
carbon cycle oceans |
spellingShingle |
carbon cycle oceans Baker, CA Henson, SA Cavan, EL Giering, SLC Yool, A Gehlen, M Belcher, A Riley, JS Smith, HEK Sanders, R Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls |
topic_facet |
carbon cycle oceans |
description |
The remineralization depth of particulate organic carbon (POC) fluxes exported from the surface ocean exerts a major control over atmospheric CO₂ levels. According to a long-held paradigm most of the POC exported to depth is associated with large particles. However, recent lines of evidence suggest that slow-sinking POC (SSPOC) may be an important contributor to this flux. Here we assess the circumstances under which this occurs. Our study uses samples collected using the Marine Snow Catcher throughout the Atlantic Ocean, from high latitudes to midlatitudes. We find median SSPOC concentrations of 5.5 μg L−1, 13 times smaller than suspended POC concentrations and 75 times higher than median fast-sinking POC (FSPOC) concentrations (0.07 μg L−1). Export fluxes of SSPOC generally exceed FSPOC flux, with the exception being during a spring bloom sampled in the Southern Ocean. In the Southern Ocean SSPOC fluxes often increase with depth relative to FSPOC flux, likely due to midwater fragmentation of FSPOC, a process which may contribute to shallow mineralization of POC and hence to reduced carbon storage. Biogeochemical models do not generally reproduce this behavior, meaning that they likely overestimate long-term ocean carbon storage. |
format |
Article in Journal/Newspaper |
author |
Baker, CA Henson, SA Cavan, EL Giering, SLC Yool, A Gehlen, M Belcher, A Riley, JS Smith, HEK Sanders, R |
author_facet |
Baker, CA Henson, SA Cavan, EL Giering, SLC Yool, A Gehlen, M Belcher, A Riley, JS Smith, HEK Sanders, R |
author_sort |
Baker, CA |
title |
Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls |
title_short |
Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls |
title_full |
Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls |
title_fullStr |
Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls |
title_full_unstemmed |
Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls |
title_sort |
slow-sinking particulate organic carbon in the atlantic ocean: magnitude, flux, and potential controls |
publisher |
Amer Geophysical Union |
publishDate |
2017 |
url |
https://eprints.utas.edu.au/45154/ https://eprints.utas.edu.au/45154/2/RODA124346.pdf |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_relation |
https://eprints.utas.edu.au/45154/2/RODA124346.pdf Baker, CA, Henson, SA, Cavan, EL orcid:0000-0003-1099-6705 , Giering, SLC, Yool, A, Gehlen, M, Belcher, A, Riley, JS, Smith, HEK and Sanders, R 2017 , 'Slow-sinking particulate organic carbon in the Atlantic Ocean: magnitude, flux, and potential controls' , Global Biogeochemical Cycles, vol. 31, no. 7 , pp. 1051-1065 , doi:10.1002/2017GB005638 <http://dx.doi.org/10.1002/2017GB005638>. |
op_doi |
https://doi.org/10.1002/2017GB005638 |
container_title |
Global Biogeochemical Cycles |
container_volume |
31 |
container_issue |
7 |
container_start_page |
1051 |
op_container_end_page |
1065 |
_version_ |
1766206103372169216 |