Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present
Using contemporary CO2 data from the subsurface Weddell Sea, the source/sink function of this region against the changing atmospheric CO2 level has been investigated. As in the central Weddell Sea, surface water is supplied by upwelling of subsurface water, the CO2 content is also forced by it. TCO2...
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Online Access: | https://oceanrep.geomar.de/id/eprint/58106/ https://oceanrep.geomar.de/id/eprint/58106/1/Hoppema.pdf https://doi.org/10.1016/j.gloplacha.2003.08.001 |
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ftoceanrep:oai:oceanrep.geomar.de:58106 2023-05-15T18:43:07+02:00 Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present Hoppema, Mario 2004-02 text https://oceanrep.geomar.de/id/eprint/58106/ https://oceanrep.geomar.de/id/eprint/58106/1/Hoppema.pdf https://doi.org/10.1016/j.gloplacha.2003.08.001 en eng Elsevier https://oceanrep.geomar.de/id/eprint/58106/1/Hoppema.pdf Hoppema, M. (2004) Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present. Global and Planetary Change, 40 (3-4). pp. 219-231. DOI 10.1016/j.gloplacha.2003.08.001 <https://doi.org/10.1016/j.gloplacha.2003.08.001>. doi:10.1016/j.gloplacha.2003.08.001 info:eu-repo/semantics/restrictedAccess Article PeerReviewed 2004 ftoceanrep https://doi.org/10.1016/j.gloplacha.2003.08.001 2023-04-07T16:06:41Z Using contemporary CO2 data from the subsurface Weddell Sea, the source/sink function of this region against the changing atmospheric CO2 level has been investigated. As in the central Weddell Sea, surface water is supplied by upwelling of subsurface water, the CO2 content is also forced by it. TCO2 data of four cruises were used to determine a robust value for the subsurface Warm Deep Water (WDW). After accounting for biological activity in the surface layer and salinity differences between the subsurface and surface waters, the forcing CO2 partial pressure (pCO2) was calculated from the TCO2 of the WDW and the conservative alkalinity as taken from the literature. As the WDW contains negligible anthropogenic CO2, the pCO2 forcing by the WDW has been prevalent both in the pre-industrial and modern Weddell Sea. The calculated pCO2 forcing amounts to 300–310 μatm at a minimum in late winter/early spring and possibly 30 μatm more during spring and summer. This figure does not represent the actual pCO2, but rather the value before air–sea exchange gets effective. Hence, in pre-industrial times when the atmospheric pCO2 was about 280 μatm, the Weddell Sea must have been a relatively strong source of atmospheric CO2. Because of the steadily rising atmospheric CO2 levels to more than the pCO2 forcing by the WDW, the Weddell Sea turned into a CO2 sink in recent times. The storage of anthropogenic CO2 in the Weddell Sea surface layer is estimated to be 4.1 mol C m−2. Applying the WDW forcing method to O2, a steady state O2 uptake from the atmosphere of 3.6 mol O2 m−2 year−1 is computed. Article in Journal/Newspaper Weddell Sea OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Weddell Weddell Sea Global and Planetary Change 40 3-4 219 231 |
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Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
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ftoceanrep |
language |
English |
description |
Using contemporary CO2 data from the subsurface Weddell Sea, the source/sink function of this region against the changing atmospheric CO2 level has been investigated. As in the central Weddell Sea, surface water is supplied by upwelling of subsurface water, the CO2 content is also forced by it. TCO2 data of four cruises were used to determine a robust value for the subsurface Warm Deep Water (WDW). After accounting for biological activity in the surface layer and salinity differences between the subsurface and surface waters, the forcing CO2 partial pressure (pCO2) was calculated from the TCO2 of the WDW and the conservative alkalinity as taken from the literature. As the WDW contains negligible anthropogenic CO2, the pCO2 forcing by the WDW has been prevalent both in the pre-industrial and modern Weddell Sea. The calculated pCO2 forcing amounts to 300–310 μatm at a minimum in late winter/early spring and possibly 30 μatm more during spring and summer. This figure does not represent the actual pCO2, but rather the value before air–sea exchange gets effective. Hence, in pre-industrial times when the atmospheric pCO2 was about 280 μatm, the Weddell Sea must have been a relatively strong source of atmospheric CO2. Because of the steadily rising atmospheric CO2 levels to more than the pCO2 forcing by the WDW, the Weddell Sea turned into a CO2 sink in recent times. The storage of anthropogenic CO2 in the Weddell Sea surface layer is estimated to be 4.1 mol C m−2. Applying the WDW forcing method to O2, a steady state O2 uptake from the atmosphere of 3.6 mol O2 m−2 year−1 is computed. |
format |
Article in Journal/Newspaper |
author |
Hoppema, Mario |
spellingShingle |
Hoppema, Mario Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present |
author_facet |
Hoppema, Mario |
author_sort |
Hoppema, Mario |
title |
Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present |
title_short |
Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present |
title_full |
Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present |
title_fullStr |
Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present |
title_full_unstemmed |
Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present |
title_sort |
weddell sea turned from source to sink for atmospheric co2 between pre-industrial time and present |
publisher |
Elsevier |
publishDate |
2004 |
url |
https://oceanrep.geomar.de/id/eprint/58106/ https://oceanrep.geomar.de/id/eprint/58106/1/Hoppema.pdf https://doi.org/10.1016/j.gloplacha.2003.08.001 |
geographic |
Weddell Weddell Sea |
geographic_facet |
Weddell Weddell Sea |
genre |
Weddell Sea |
genre_facet |
Weddell Sea |
op_relation |
https://oceanrep.geomar.de/id/eprint/58106/1/Hoppema.pdf Hoppema, M. (2004) Weddell Sea turned from source to sink for atmospheric CO2 between pre-industrial time and present. Global and Planetary Change, 40 (3-4). pp. 219-231. DOI 10.1016/j.gloplacha.2003.08.001 <https://doi.org/10.1016/j.gloplacha.2003.08.001>. doi:10.1016/j.gloplacha.2003.08.001 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1016/j.gloplacha.2003.08.001 |
container_title |
Global and Planetary Change |
container_volume |
40 |
container_issue |
3-4 |
container_start_page |
219 |
op_container_end_page |
231 |
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1766232946721685504 |