June 30 , 2016

Abrupt and short-lived "impact winter" conditions have commonly been implicated as the main mechanism leading to the mass extinction at the Cretaceous-Paleogene (K-Pg) boundary (ca. 66 Ma), marking the end of the reign of the non-avian dinosaurs. However, so far only limited evidence has been available for such a climatic perturbation. Here we perform high-resolution TEX86 organic paleothermometry on three shallow cores from the New Jersey paleoshelf, (northeastern USA) to assess the impact-provoked climatic perturbations immediately following the K-Pg impact and to place these short-term events in the context of long-term climate evolution. We provide evidence of impact-provoked, severe climatic cooling immediately following the K-Pg impact. This so-called "impact winter" occurred superimposed on a long-term cooling trend that followed a warm phase in the latest Cretaceous.

Johan Vellekoop, Selen Esmeray-Senlet, Kenneth G. Miller, James V. Browning, Appy Sluijs, Bas van de Schootbrugge, Jaap S. Sinninghe Damsté, and Henk Brinkhuis (2016)
Evidence for Cretaceous-Paleogene boundary bolide "impact winter" conditions from New Jersey, USA.
Geology (advance online publication)
doi:10.1130/G37961.1