Alkenones as paleoceanographic proxies

Julian P. Sachs, Ralph R. Schneider, Timothy I. Eglinton, Katherine Haines Freeman, Gerald Ganssen, Jerry F. McManus, Delia W. Oppo

Research output: Contribution to journalArticle

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Abstract

Alkenone-derived estimates of temperature and CO2 are contributing to our understanding of Earth's climate history. In order to increase confidence in alkenone-based climate proxies we recommend the following actions. First, the sedimentary component or fraction containing alkenones should be identified in order to assess the impact of horizontal advection and vertical mixing on alkenone-derived temperature and CO2 estimates. Second, differential mixing rates of alkenone-containing particles and sand-sized foraminifera should be quantified by independent dating of the two phases. Until that is accomplished, apparent temporal offsets of climate proxies in the two phases should be interpreted cautiously. Third, the stability of the unsaturation ratio and carbon isotopic compositions of alkenones during all phases of diagenesis should be confirmed. Both field and laboratory observations are required. Fourth, future alkenone investigations should be coupled with other paleoclimate proxy measurements at high-deposition-rate-sites in a variety of oceanographic settings. In upwelling regions and in the vicinity of river plumes, salinity and nutrient proxies should be measured since changes in these parameters may affect alkenone biosynthesis.

Original languageEnglish (US)
JournalGeochemistry, Geophysics, Geosystems
Volume1
Issue number11
DOIs
StatePublished - Nov 1 2000

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alkenone
climate
Biosynthesis
Advection
Deposition rates
Nutrients
biosynthesis
Sand
Carbon
Rivers
Earth (planet)
nutrients
upwelling water
estimates
salinity
dating
advection
rivers
Temperature
sands

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Geochemistry and Petrology

Cite this

Sachs, J. P., Schneider, R. R., Eglinton, T. I., Freeman, K. H., Ganssen, G., McManus, J. F., & Oppo, D. W. (2000). Alkenones as paleoceanographic proxies. Geochemistry, Geophysics, Geosystems, 1(11). https://doi.org/10.1029/2000GC000059
Sachs, Julian P. ; Schneider, Ralph R. ; Eglinton, Timothy I. ; Freeman, Katherine Haines ; Ganssen, Gerald ; McManus, Jerry F. ; Oppo, Delia W. / Alkenones as paleoceanographic proxies. In: Geochemistry, Geophysics, Geosystems. 2000 ; Vol. 1, No. 11.
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Sachs, JP, Schneider, RR, Eglinton, TI, Freeman, KH, Ganssen, G, McManus, JF & Oppo, DW 2000, 'Alkenones as paleoceanographic proxies', Geochemistry, Geophysics, Geosystems, vol. 1, no. 11. https://doi.org/10.1029/2000GC000059

Alkenones as paleoceanographic proxies. / Sachs, Julian P.; Schneider, Ralph R.; Eglinton, Timothy I.; Freeman, Katherine Haines; Ganssen, Gerald; McManus, Jerry F.; Oppo, Delia W.

In: Geochemistry, Geophysics, Geosystems, Vol. 1, No. 11, 01.11.2000.

Research output: Contribution to journalArticle

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Sachs JP, Schneider RR, Eglinton TI, Freeman KH, Ganssen G, McManus JF et al. Alkenones as paleoceanographic proxies. Geochemistry, Geophysics, Geosystems. 2000 Nov 1;1(11). https://doi.org/10.1029/2000GC000059