Stable isotope ratios of foraminifera and sea surface temperature estimation of sediment core W2804A-14
Carbon isotopically based estimates of CO2 levels have been generated from a record of the photosynthetic fractionation of 13C (epsilon p) in a central equatorial Pacific sediment core that spans the last ~255 ka. Contents of 13C in phytoplanktonic biomass were determined by analysis of C37 alkadien...
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1994
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.729801 2024-09-15T18:31:08+00:00 Stable isotope ratios of foraminifera and sea surface temperature estimation of sediment core W2804A-14 Jasper, John P Hayes, John M Mix, Alan C Prahl, Frederick G LATITUDE: 0.953000 * LONGITUDE: -138.955000 * DATE/TIME START: 1984-02-23T00:00:00 * DATE/TIME END: 1984-02-23T00:00:00 1994 application/zip, 3 datasets https://doi.pangaea.de/10.1594/PANGAEA.729801 https://doi.org/10.1594/PANGAEA.729801 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.729801 https://doi.org/10.1594/PANGAEA.729801 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Jasper, John P; Hayes, John M; Mix, Alan C; Prahl, Frederick G (1994): Photosynthetic fractionation of 13C and concentrations of dissolved CO2 in the central equatorial Pacific during the last 255,000 years. Paleoceanography, 9(6), 781-798, https://doi.org/10.1029/94PA02116 GC Gravity corer W8402A W8402A-14 Wecoma dataset publication series 1994 ftpangaea https://doi.org/10.1594/PANGAEA.72980110.1029/94PA02116 2024-07-24T02:31:20Z Carbon isotopically based estimates of CO2 levels have been generated from a record of the photosynthetic fractionation of 13C (epsilon p) in a central equatorial Pacific sediment core that spans the last ~255 ka. Contents of 13C in phytoplanktonic biomass were determined by analysis of C37 alkadienones. These compounds are exclusive products of Prymnesiophyte algae which at present grow most abundantly at depths of 70-90 m in the central equatorial Pacific. A record of the isotopic compostion of dissolved CO2 was constructed from isotopic analyses of the planktonic foraminifera Neogloboquadrina dutertrei, which calcifies at 70-90 m in the same region. Values of epsilon p, derived by comparison of the organic and inorganic delta values, were transformed to yield concentrations of dissolved CO2 (c e) based on a new, site-specific calibration of the relationship between epsilon p and c e. The calibration was based on reassessment of existing epsilon p versus c e data, which support a physiologically based model in which epsilon p is inversely related to c e. Values of PCO2, the partial pressure of CO2 that would be in equilibrium with the estimated concentrations of dissolved CO2, were calculated using Henry's law and the temperature determined from the alkenone-unsaturation index UK 37. Uncertainties in these values arise mainly from uncertainties about the appropriateness (particularly over time) of the site-specific relationship between epsilon p and 1/c e. These are discussed in detail and it is concluded that the observed record of epsilon p most probably reflects significant variations in Delta pCO2, the ocean-atmosphere disequilibrium, which appears to have ranged from ~110 µatm during glacial intervals (ocean > atmosphere) to ~60 µatm during interglacials. Fluxes of CO2 to the atmosphere would thus have been significantly larger during glacial intervals. If this were characteristic of large areas of the equatorial Pacific, then greater glacial sinks for the equatorially evaded CO2 must have existed ... Other/Unknown Material Planktonic foraminifera PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-138.955000,-138.955000,0.953000,0.953000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
GC Gravity corer W8402A W8402A-14 Wecoma |
spellingShingle |
GC Gravity corer W8402A W8402A-14 Wecoma Jasper, John P Hayes, John M Mix, Alan C Prahl, Frederick G Stable isotope ratios of foraminifera and sea surface temperature estimation of sediment core W2804A-14 |
topic_facet |
GC Gravity corer W8402A W8402A-14 Wecoma |
description |
Carbon isotopically based estimates of CO2 levels have been generated from a record of the photosynthetic fractionation of 13C (epsilon p) in a central equatorial Pacific sediment core that spans the last ~255 ka. Contents of 13C in phytoplanktonic biomass were determined by analysis of C37 alkadienones. These compounds are exclusive products of Prymnesiophyte algae which at present grow most abundantly at depths of 70-90 m in the central equatorial Pacific. A record of the isotopic compostion of dissolved CO2 was constructed from isotopic analyses of the planktonic foraminifera Neogloboquadrina dutertrei, which calcifies at 70-90 m in the same region. Values of epsilon p, derived by comparison of the organic and inorganic delta values, were transformed to yield concentrations of dissolved CO2 (c e) based on a new, site-specific calibration of the relationship between epsilon p and c e. The calibration was based on reassessment of existing epsilon p versus c e data, which support a physiologically based model in which epsilon p is inversely related to c e. Values of PCO2, the partial pressure of CO2 that would be in equilibrium with the estimated concentrations of dissolved CO2, were calculated using Henry's law and the temperature determined from the alkenone-unsaturation index UK 37. Uncertainties in these values arise mainly from uncertainties about the appropriateness (particularly over time) of the site-specific relationship between epsilon p and 1/c e. These are discussed in detail and it is concluded that the observed record of epsilon p most probably reflects significant variations in Delta pCO2, the ocean-atmosphere disequilibrium, which appears to have ranged from ~110 µatm during glacial intervals (ocean > atmosphere) to ~60 µatm during interglacials. Fluxes of CO2 to the atmosphere would thus have been significantly larger during glacial intervals. If this were characteristic of large areas of the equatorial Pacific, then greater glacial sinks for the equatorially evaded CO2 must have existed ... |
format |
Other/Unknown Material |
author |
Jasper, John P Hayes, John M Mix, Alan C Prahl, Frederick G |
author_facet |
Jasper, John P Hayes, John M Mix, Alan C Prahl, Frederick G |
author_sort |
Jasper, John P |
title |
Stable isotope ratios of foraminifera and sea surface temperature estimation of sediment core W2804A-14 |
title_short |
Stable isotope ratios of foraminifera and sea surface temperature estimation of sediment core W2804A-14 |
title_full |
Stable isotope ratios of foraminifera and sea surface temperature estimation of sediment core W2804A-14 |
title_fullStr |
Stable isotope ratios of foraminifera and sea surface temperature estimation of sediment core W2804A-14 |
title_full_unstemmed |
Stable isotope ratios of foraminifera and sea surface temperature estimation of sediment core W2804A-14 |
title_sort |
stable isotope ratios of foraminifera and sea surface temperature estimation of sediment core w2804a-14 |
publisher |
PANGAEA |
publishDate |
1994 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.729801 https://doi.org/10.1594/PANGAEA.729801 |
op_coverage |
LATITUDE: 0.953000 * LONGITUDE: -138.955000 * DATE/TIME START: 1984-02-23T00:00:00 * DATE/TIME END: 1984-02-23T00:00:00 |
long_lat |
ENVELOPE(-138.955000,-138.955000,0.953000,0.953000) |
genre |
Planktonic foraminifera |
genre_facet |
Planktonic foraminifera |
op_source |
Supplement to: Jasper, John P; Hayes, John M; Mix, Alan C; Prahl, Frederick G (1994): Photosynthetic fractionation of 13C and concentrations of dissolved CO2 in the central equatorial Pacific during the last 255,000 years. Paleoceanography, 9(6), 781-798, https://doi.org/10.1029/94PA02116 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.729801 https://doi.org/10.1594/PANGAEA.729801 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1594/PANGAEA.72980110.1029/94PA02116 |
_version_ |
1810472742181404672 |