Extreme warming of tropical waters during the Paleocene-Eocene Thermal Maximum

The Paleocene–Eocene Thermal Maximum (PETM), ca. 56 Ma, was a major global environmental perturbation attributed to a rapid rise in the concentration of greenhouse gases in the atmosphere. Geochemical records of tropical sea-surface temperatures (SSTs) from the PETM are rare and are typically affect...

Full description

Bibliographic Details
Published in:Geology
Main Authors: Aze, T., Pearson, P.N., Dickson, A.J., Badger, M.P.S., Bown, P.R., Pancost, R.D., Gibbs, S.J., Huber, B.T., Leng, M.J., Coe, A.L., Cohen, A.S., Foster, G.L.
Format: Article in Journal/Newspaper
Language:English
Published: Geological Society of America 2014
Subjects:
Planktonic foraminifera
Online Access:http://nora.nerc.ac.uk/id/eprint/508323/
https://nora.nerc.ac.uk/id/eprint/508323/1/739.full.pdf
https://doi.org/10.1130/G35637.1
Description
Summary:The Paleocene–Eocene Thermal Maximum (PETM), ca. 56 Ma, was a major global environmental perturbation attributed to a rapid rise in the concentration of greenhouse gases in the atmosphere. Geochemical records of tropical sea-surface temperatures (SSTs) from the PETM are rare and are typically affected by post-depositional diagenesis. To circumvent this issue, we have analyzed oxygen isotope ratios (d18O) of single specimens of exceptionally well-preserved planktonic foraminifera from the PETM in Tanzania (~19°S paleolatitude), which yield extremely low d18O, down to <–5‰. After accounting for changes in seawater chemistry and pH, we estimate from the foraminifer d18O that tropical SSTs rose by >3 °C during the PETM and may have exceeded 40 °C. Calcareous plankton are absent from a large part of the Tanzania PETM record; extreme environmental change may have temporarily caused foraminiferal exclusion.

Similar Items