Archaeal lipid biomarker constraints on the Paleocene-Eocene carbon isotope excursion

Abstract

The Paleocene-Eocene Thermal Maximum (c. 55 million years ago) was a period associated with massive carbon injection into the atmosphere, yet discrepancies in carbon isotope proxy records have led to substantial uncertainties in the source, scale, and timing of carbon emissions. Here, the authors propose that membrane lipids of marine planktonic archaea can reliably record the carbon isotope excursion and surface ocean warming, giving a new constraint for the source and size of the PETM carbon emissions.