Skip to content

Research at St Andrews

The evolution of deep ocean chemistry and respired carbon in the Eastern Equatorial Pacific over the last deglaciation

Research output: Contribution to journalArticle



Maria de la Fuente, Eva Calvo, Luke Skinner, Carles Pelejero, David Evans, Wolfgang Müller, Patricia Povea, Isabel Cacho

School/Research organisations


It has been shown that the deep Eastern Equatorial Pacific (EEP) region was poorly ventilated during the Last Glacial Maximum (LGM) relative to Holocene values. This finding suggests a more efficient biological pump, which indirectly supports the idea of increased carbon storage in the deep ocean contributing to lower atmospheric CO2 during the last glacial. However, proxies related to respired carbon are needed in order to directly test this proposition. Here we present Cibicides wuellerstorfi B/Ca ratios from Ocean Drilling Program Site 1240 measured by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) as a proxy for deep water carbonate saturation state (Δ[CO32−], and therefore [CO32−]), along with δ13C measurements. In addition, the U/Ca ratio in foraminiferal coatings has been analyzed as an indicator of oxygenation changes. Our results show lower [CO32−], δ13C, and [O2] values during the LGM, which would be consistent with higher respired carbon levels in the deep EEP driven, at least in part, by reduced deep water ventilation. However, the difference between LGM and Holocene [CO32−] observed at our site is relatively small, in accordance with other records from across the Pacific, suggesting that a “counteracting” mechanism, such as seafloor carbonate dissolution, also played a role. If so, this mechanism would have increased average ocean alkalinity, allowing even more atmospheric CO2 to be “sequestered” by the ocean. Therefore, the deep Pacific Ocean very likely stored a significant amount of atmospheric CO2 during the LGM, specifically due to a more efficient biological carbon pump and also an increase in average ocean alkalinity.


Original languageEnglish
VolumeEarly View
Early online date20 Dec 2017
StateE-pub ahead of print - 20 Dec 2017

    Research areas

  • Marine carbon cycle, Carbonate chemistry, Ocean circulation, Glacial-interglacial cycles, Soft-tissue pump efficiency, Seafloor calcite dissolution

Discover related content
Find related publications, people, projects and more using interactive charts.

View graph of relations

Related by author

  1. The accuracy of mid-Pliocene δ18O-based ice volume and sea level reconstructions

    Raymo, M. E., Kozdon, R., Evans, D., Lisiecki, L. & Ford, H. L. 2 Dec 2017 In : Earth Science Reviews. 177, p. 291-302

    Research output: Contribution to journalReview article

  2. Size-dependent response of foraminiferal calcification to seawater carbonate chemistry

    Henehan, M. J., Evans, D., Shankle, M., Burke, J. E., Foster, G. L., Anagnostou, E., Chalk, T. B., Stewart, J. A., Alt, C. H. S., Durrant, J. & Hull, P. M. 10 Jul 2017 In : Biogeosciences. 14, p. 3287-3308 22 p.

    Research output: Contribution to journalArticle

  3. The DeepMIP contribution to PMIP4: experimental design for model simulations of the EECO, PETM, and pre-PETM (version 1.0)

    Lunt, D. J. , Huber, M. , Anagnostou, E. , Baatsen, M. L. J. , Caballero, R. , DeConto, R. , Dijkstra, H. A. , Donnadieu, Y. , Evans, D. , Feng, R. , Foster, G. L. , Gasson, E. , Von Der Heydt, A. S. , Hollis, C. J. , Inglis, G. N. , Jones, S. M. , Kiehl, J. , Turner, S. K. , Korty, R. L. , Kozdon, R. & 26 others Krishnan, S., Ladant, J. B., Langebroek, P., Lear, C. H., LeGrande, A. N., Littler, K., Markwick, P., Otto-Bliesner, B., Pearson, P., Poulsen, C. J., Salzmann, U., Shields, C., Snell, K., Stärz, M., Super, J., Tabor, C., Tierney, J. E., Tourte, G. J. L., Tripati, A., Upchurch, G. R., Wade, B. S., Wing, S. L., Winguth, A. M. E., Wright, N. M., Zachos, J. C. & Zeebe, R. E. 23 Feb 2017 In : Geoscientific Model Development. 10, 2, p. 889-901 13 p.

    Research output: Contribution to journalArticle

Related by journal

  1. Calibration of the B/Ca proxy in the planktic foraminifer Orbulina universa to Paleocene seawater conditions

    Haynes, L. L., Hönisch, B., Dyez, K. A., Holland, K., Rosenthal, Y., Fish, C. R., Subhas, A. V. & Rae, J. W. B. Jun 2017 In : Paleoceanography. 32, 6, p. 580-599

    Research output: Contribution to journalArticle

  2. Geochemical imprints of genotypic variants of Globigerina bulloides in the Arabian Sea

    Sadekov, A. Y., Darling, K. F., Ishimura, T., Wade, C. M., Kimoto, K., Singh, A. D., Anand, P., Kroon, D., Jung, S., Ganssen, G., Ganeshram, R., Tsunogai, U. & Elderfield, H. 29 Oct 2016 In : Paleoceanography. 31, 10, p. 1440-1452 13 p.

    Research output: Contribution to journalArticle

  3. The glacial mid-depth radiocarbon bulge and its implications for the overturning circulation

    Burke, A., Stewart, A. L., Adkins, J. F., Ferrari, R., Jansen, M. F. & Thompson, A. F. 2015 In : Paleoceanography. Early view

    Research output: Contribution to journalArticle

  4. Middle Miocene climate instability associated with high-amplitude CO2 variability

    Greenop, R., Foster, G. L., Wilson, P. A. & Lear, C. H. Sep 2014 In : Paleoceanography. 29, 9, p. 845-853 9 p.

    Research output: Contribution to journalArticle

ID: 251813552