^1,2Alfio Alessandro Chiarenza,³Alexander Farnsworth,²Philip D. Mannion,³Daniel J. Lunt,³Paul J. Valdes,¹Joanna V. Morgan,¹Peter A. Allison
Proceedings of the National Academy of Sciences of the United States of America 117, 17084-17093 Link to Article [DOI: https://doi.org/10.1073/pnas.2006087117]
¹Department of Earth Science and Engineering, Imperial College London, South Kensington, SW7 2AZ London, United Kingdom;
²Department of Earth Sciences, University College London, WC1E 6BT London, United Kingdom;
³School of Geographical Sciences, University of Bristol, BS8 1TH Bristol, United Kingdom

The Cretaceous/Paleogene mass extinction, 66 Ma, included the demise of non-avian dinosaurs. Intense debate has focused on the relative roles of Deccan volcanism and the Chicxulub asteroid impact as kill mechanisms for this event. Here, we combine fossil-occurrence data with paleoclimate and habitat suitability models to evaluate dinosaur habitability in the wake of various asteroid impact and Deccan volcanism scenarios. Asteroid impact models generate a prolonged cold winter that suppresses potential global dinosaur habitats. Conversely, long-term forcing from Deccan volcanism (carbon dioxide [CO₂]-induced warming) leads to increased habitat suitability. Short-term (aerosol cooling) volcanism still allows equatorial habitability. These results support the asteroid impact as the main driver of the non-avian dinosaur extinction. By contrast, induced warming from volcanism mitigated the most extreme effects of asteroid impact, potentially reducing the extinction severity.