Chicxulub impact winter sustained by fine silicate dust
Senel, C.B.; Kaskes, P.; Temel, O.; Vellekoop, J.; Goderis, S.; DePalma, R.; Prins, M.A.; Claeys, P.; Karatekin, Ö. (2023). Chicxulub impact winter sustained by fine silicate dust. Nature Geoscience 16(11): 1033-1040. https://dx.doi.org/10.1038/s41561-023-01290-4 In: Nature Geoscience. Nature Publishing Group: London. ISSN 1752-0894; e-ISSN 1752-0908, more |  |
| Authors | | Top | - Senel, C.B.
- Kaskes, P., more
- Temel, O., more
| - Vellekoop, J., more
- Goderis, S., more
- DePalma, R.
| - Prins, M.A.
- Claeys, P., more
- Karatekin, Ö., more
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| Abstract | The Chicxulub impact is thought to have triggered a global winter at the Cretaceous-Palaeogene (K-Pg) boundary 66 million years ago. Yet the climatic consequences of the various debris injected into the atmosphere following the Chicxulub impact remain unclear, and the exact killing mechanisms of the K-Pg mass extinction remain poorly constrained. Here we present palaeoclimate simulations based on sedimentological constraints from an expanded terrestrial K-Pg boundary deposit in North Dakota, United States, to evaluate the relative and combined effects of impact-generated silicate dust and sulfur, as well as soot from wildfires, on the post-impact climate. The measured volumetric size distribution of silicate dust suggests a larger contribution of fine dust (~0.8–8.0 μm) than previously appreciated. Our simulations of the atmospheric injection of such a plume of micrometre-sized silicate dust suggest a long atmospheric lifetime of 15yr, contributing to a global-average surface temperature falling by as much as 15°C. Simulated changes in photosynthetic active solar radiation support a dust-induced photosynthetic shut-down for almost 2 yr post-impact. We suggest that, together with additional cooling contributions from soot and sulfur, this is consistent with the catastrophic collapse of primary productivity in the aftermath of the Chicxulub impact. |
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