Records of post–Cretaceous-Tertiary boundary millennial-scale cooling from the western Tethys: A smoking gun for the impact-winter hypothesis?

The record of both dinoflagellate cysts and benthic foraminifera across the Cretaceous-Tertiary boundary at El Kef, Tunisia, reveals a brief expansion of the Boreal bioprovince into the western Tethys, suggesting that an ∼2 k.y. cooling occurred during the earliest Danian. We show that this prolonged cooling phase is consistent with the oceanographic response to an impact winter.