Surface ocean warming and acidification driven by rapid carbon release precedes Paleocene-Eocene Thermal Maximum.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35294237.
- Also identified by DOI 10.1126/sciadv.abg1025 and PMC identifier 8926327.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The Paleocene-Eocene Thermal Maximum (PETM) is recognized by a major negative carbon isotope (δ<sup>13</sup>C) excursion (CIE) signifying an injection of isotopically light carbon into exogenic reservoirs, the mass, source, and tempo of which continue to be debated. Evidence of a transient precursor carbon release(s) has been identified in a few localities, although it remains equivocal whether there is a global signal. Here, we present foraminiferal δ<sup>13</sup>C records from a marine continental margin section, which reveal a 1.0 to 1.5‰ negative pre-onset excursion (POE), and concomitant rise in sea surface temperature of at least 2°C and a decline in ocean pH. The recovery of both δ<sup>13</sup>C and pH before the CIE onset and apparent absence of a POE in deep-sea records suggests a rapid (< ocean mixing time scales) carbon release, followed by recovery driven by deep-sea mixing. Carbon released during the POE is therefore likely more similar to ongoing anthropogenic emissions in mass and rate than the main CIE.