title: Rapid short-term cooling following the Chicxulub impact at the Cretaceous-Paleogene boundary.
abstract: The mass extinction at the Cretaceous-Paleogene boundary, ∼ 66 Ma, is thought to be caused by the impact of an asteroid at Chicxulub, present-day Mexico. Although the precise mechanisms that led to this mass extinction remain enigmatic, most postulated scenarios involve a short-lived global cooling, a so-called "impact winter" phase. Here we document a major decline in sea surface temperature during the first months to decades following the impact event, using TEX86 paleothermometry of sediments from the Brazos River section, Texas. We interpret this cold spell to reflect, to our knowledge, the first direct evidence for the effects of the formation of dust and aerosols by the impact and their injection in the stratosphere, blocking incoming solar radiation. This impact winter was likely a major driver of mass extinction because of the resulting global decimation of marine and continental photosynthesis.
authors.affiliation: Marine Palynology, Department of Earth Sciences, Faculty of Geosciences, Laboratory of Palaeobotany and Palynology, Utrecht University, 3584 CD, Utrecht, The Netherlands; j.vellekoop@uu.nl.
authors.forename: Johan
authors.initials: J
authors.lastname: Vellekoop
authors.affiliation: Marine Palynology, Department of Earth Sciences, Faculty of Geosciences, Laboratory of Palaeobotany and Palynology, Utrecht University, 3584 CD, Utrecht, The Netherlands;
authors.forename: Appy
authors.initials: A
authors.lastname: Sluijs
authors.affiliation: Eventstratigraphy, Sedimentology, Faculty of Earth- and Life Sciences, VU University Amsterdam, 1081 HV, Amsterdam, The Netherlands;
authors.forename: Jan
authors.initials: J
authors.lastname: Smit
authors.affiliation: Geochemistry, Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584 CD, Utrecht, The Netherlands; andDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute of Sea Research, 1790 AB, Den Burg, Texel, The Netherlands.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schouten
authors.affiliation: Geochemistry, Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584 CD, Utrecht, The Netherlands; and.
authors.forename: Johan W H
authors.initials: JW
authors.lastname: Weijers
authors.affiliation: Geochemistry, Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584 CD, Utrecht, The Netherlands; andDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute of Sea Research, 1790 AB, Den Burg, Texel, The Netherlands.
authors.forename: Jaap S
authors.initials: JS
authors.lastname: Sinninghe Damsté
authors.affiliation: Marine Palynology, Department of Earth Sciences, Faculty of Geosciences, Laboratory of Palaeobotany and Palynology, Utrecht University, 3584 CD, Utrecht, The Netherlands;
authors.forename: Henk
authors.initials: H
authors.lastname: Brinkhuis
mesh_terms: D000336:Aerosols; D001272:Atmosphere / Q000032:analysis; D057231:Climate Change / Q000266:history*; D004391:Dust; D019419:Evolution, Planetary; D053476:Extinction, Biological; D056908:Foraminifera / Q000302:isolation & purification; D019015:Geologic Sediments / Q000737:chemistry* / Q000382:microbiology; D049690:History, Ancient; D018543:Minor Planets; D008962:Models, Theoretical; D010316:Particle Size; D013696:Temperature; D013781:Texas
chemical_list: D000336:Aerosols; D004391:Dust
keywords: Climate change; K-Pg boundary; bolide impact; organic paleothermometry