Terrestrial evidence for volcanogenic sulfate-driven cooling event ~30 kyr before the Cretaceous-Paleogene mass extinction.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39693422.
- Also identified by DOI 10.1126/sciadv.ado5478 and PMC identifier 11654674.
- 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
Alongside the Chicxulub meteorite impact, Deccan volcanism is considered a primary trigger for the Cretaceous-Paleogene (K-Pg) mass extinction. Models suggest that volcanic outgassing of carbon and sulfur-potent environmental stressors-drove global temperature change, but the relative timing, duration, and magnitude of such change remains uncertain. Here, we use the organic paleothermometer MBT'<sub>5me</sub> and the carbon-isotope composition of two K-Pg-spanning lignites from the western Unites States, to test models of volcanogenic air temperature change in the ~100 kyr before the mass extinction. Our records show long-term warming of ~3°C, probably driven by Deccan CO<sub>2</sub> emissions, and reveal a transient (<10 kyr) ~5°C cooling event, coinciding with the peak of the Poladpur "pulse" of Deccan eruption ~30 kyr before the K-Pg boundary. This cooling was likely caused by the aerosolization of volcanogenic sulfur. Temperatures returned to pre-event values before the mass extinction, suggesting that, from the terrestrial perspective, volcanogenic climate change was not the primary cause of K-Pg extinction.