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

• 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: unknown
• Published: 2014
• Subjects: Planktonic foraminifera
• Online Access: https://oro.open.ac.uk/45563/; https://oro.open.ac.uk/45563/1/Geology_2014_Aze_G35637.1.Offprint.pdf; https://oro.open.ac.uk/45563/7/__userdata_documents2_rfw62_Desktop_badgetr.pdf; https://oro.open.ac.uk/45563/8/Geology_2014_Aze_G35637.1.Offprint.pdf; https://oro.open.ac.uk/45563/9/__userdata_documents2_rfw62_Desktop_badgetr.pdf; https://oro.open.ac.uk/45563/24/__userdata_documents2_rfw62_Desktop_badgetr.pdf; https://doi.org/10.1130/G35637.1

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 (δ 18 O) of single specimens of exceptionally well-preserved planktonic foraminifera from the PETM in Tanzania (~19°S paleolatitude), which yield extremely low δ 18 O, down to <–5‰. After accounting for changes in seawater chemistry and pH, we estimate from the foraminifer δ 18 O 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.