Carbon isotopic disequilibrium in polar planktonic Foraminifera and its impact 
on modern and Last Glacial Maximum reconstructions

Kohfeld, K. E.; Anderson, R. F.; Lynch-Stieglitz, J.

doi:10.1029/1999PA900049

Item

ITEM ACTIONSEXPORT

Add to Basket

Local TagsRelease HistoryDetailsSummary

Released

Journal Article

Carbon isotopic disequilibrium in polar planktonic Foraminifera and its impact on modern and Last Glacial Maximum reconstructions

MPS-Authors

/persons/resource/persons62443

Kohfeld, K. E.
Research Group Paleo-Climatology, Dr. S. P. Harrison, Max Planck Institute for Biogeochemistry, Max Planck Society;

External Resource

http://dx.doi.org/10.1029/1999PA900049
(Publisher version)

Fulltext (restricted access)

There are currently no full texts shared for your IP range.

Fulltext (public)

There are no public fulltexts stored in PuRe

Supplementary Material (public)

There is no public supplementary material available

Citation

Kohfeld, K. E., Anderson, R. F., & Lynch-Stieglitz, J. (2000). Carbon isotopic disequilibrium in polar planktonic Foraminifera and its impact on modern and Last Glacial Maximum reconstructions. Paleoceanography, 15(1), 53-64. doi:10.1029/1999PA900049.

Cite as: https://hdl.handle.net/11858/00-001M-0000-000E-CCA4-5

Abstract

Calibration studies of Neogloboquadrina pachyderma (sinistral: coiling, hereinafter referred to as N. pachyderma (s.)) in the South Atlantic raise questions about the interpretation of this species' carbon isotope composition as a paleoceanographic tracer of Southern Ocean surface nutrient contents. Carbon isotope disequilibrium between delta(13)C of total CO₂ (TCO₂) of seawater and delta(13)C of N. pachyderma (s.) increases systematically between 70 degrees and 40 degrees S. Several effects could cause the observed carbon isotope disequilibrium, including a combination of foraminiferal diet, calcification temperature, and carbonate ion chemistry. Combining these corrections to the delta(13)C of N. pachyderma (s.) improves the reconstruction of the delta(13)C of seawater TCO₂ between 0 and 200 m in the modern South Atlantic. With these corrections applied, the delta(13)C for equilibrium calcite reconstructed from N. pachyderma (s.) at the Last Glacial Maximum is very similar to preindustrial values, suggesting that one cannot rule out the possibility that surface nutrient concentrations in the South Atlantic Ocean were comparable to today. However, the magnitude of the uncertainties associated with these corrections make it difficult to assess absolute paleonutrient concentrations with much confidence.