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Estimating Piacenzian sea surface temperature using an alkenone-calibrated transfer function

Harry J. Dowsett·Marci M. Robinson·Kevin M. Foley
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Abstract

Stationarity of environmental preferences is a primary assumption required for any paleoenvironmental reconstruction using fossil materials based upon calibration to modern organisms. Confidence in this assumption decreases the further back in time one goes, and the validity of the assumption that species temperature tolerances have not changed over time has been challenged in Pliocene studies. We use paired U K′ 37 (unsaturated ketones with 37 carbon atoms) sea surface temperature (SST) and faunal assemblage data to directly calibrate North Atlantic Piacenzian planktonic foraminifer assemblages to Piacenzian alkenone paleotemperature estimates to provide an alternative paleoceanographic reconstruction approach that does not rely on stationarity. In doing so, we extend Pliocene SST estimates to sites where only quantitative faunal assemblage data were previously available and improve the spatial resolution of the North Atlantic SST reconstruction.

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Harry J. Dowsett, Marci M. Robinson, Kevin M. Foley. 2021-06-10. Estimating Piacenzian sea surface temperature using an alkenone-calibrated transfer function. https://doi.org/10.3133/sir20215051

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