Dust from the dinosaur-killing impact ushered in years of global darkness

Dinosaur illustration Dakotaraptor steini in the months following the Chicxulub impact about 66 million years ago. (Image credit: Artwork by © Mark A. Garlick)

About 66 million years ago, an asteroid the size of a city crashed into what is now the Yucatan Peninsula, ushering in a long period of darkness that extinguished the non-birds dinosaurs. Researchers have long debated exactly what aspect of this event, known as the Chicxulub Impact, caused the rapid climate change. Were they sulfur particles from evaporated sedimentary rocks? Soot from the ensuing global fires? Or dust from the Yucatan rock itself?

Now new research claims dust is the deadliest aspect of the impact. While soot and sulfur contributed to the global darkness and the shock winter that stopped photosynthesis for almost two years, fine granite dust dispersed by the impact remains in the atmosphere for up to 15 years. The asteroid impact set off an extinction spiral that killed 75% of all species on the planet.

Paleoclimate model simulations show dust transport across the planet, indicating that the Cretaceous world was surrounded by silicate dust within days of the Chicxulub impact. (Image credit: Simulation by Cem Berk Senel (ROB-VUB))

“We found that the dust-induced disruption of photosynthetic activity was enormous, much larger than we had expected before this study,” lead researcher Jem Burke Sennellpostdoctoral fellow in planetary sciences at the Royal Observatory of Belgium, told Live Science.

Leave a Comment

Your email address will not be published. Required fields are marked *