Deep ocean ventilation, carbon isotopes, marine sedimentation and the deglacial CO2 rise

Tschumi, Tobias; Joos, Fortunat; Gehlen, M.; Heinze, C. (2010). Deep ocean ventilation, carbon isotopes, marine sedimentation and the deglacial CO2 rise. Climate of the past, 6(5), pp. 1895-1958. Göttingen: Copernicus Publications 10.5194/cpd-6-1895-2010

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The link between the atmospheric CO2 level and the ventilation state of the deep ocean is an important building block of the key hypotheses put forth to explain glacial-interglacial CO2 fluctuations. In this study, we systematically examine the sensitivity of atmospheric CO2 and its carbon isotope composition to changes in deep ocean ventilation, the ocean carbon pumps, and sediment formation in a global three-dimensional ocean-sediment carbon cycle model. Our results provide support for the hypothesis that a break up of Southern Ocean stratification and invigorated deep ocean ventilation were the dominant drivers for the early deglacial CO2 rise of ~35 ppm between the Last Glacial Maximum and 14.6 ka BP. Another rise of 10 ppm until the end of the Holocene is attributed to carbonate compensation responding to the early deglacial change in ocean circulation. Our reasoning is based on a multi-proxy analysis which indicates that an acceleration of deep ocean ventilation during the early deglaciation is not only consistent with recorded atmospheric CO2 but also with the reconstructed opal sedimentation peak in the Southern Ocean at around 16 ka BP, the record of atmospheric δ13CCO2, and the reconstructed changes in the Pacific CaCO3 saturation horizon.

Item Type:

Journal Article (Original Article)

Division/Institute:

08 Faculty of Science > Physics Institute > Climate and Environmental Physics

UniBE Contributor:

Tschumi, Tobias and Joos, Fortunat

ISSN:

1814-9324

Publisher:

Copernicus Publications

Language:

English

Submitter:

Factscience Import

Date Deposited:

04 Oct 2013 14:16

Last Modified:

26 Apr 2017 02:25

Publisher DOI:

10.5194/cpd-6-1895-2010

Web of Science ID:

000295356800007

BORIS DOI:

10.7892/boris.4533

URI:

https://boris.unibe.ch/id/eprint/4533 (FactScience: 208778)

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