CU study says asteroid firestorm likely killed dinosaurs and 80 percent of life on Earth

By: Steve Tuesday April 2, 2013 Tags: Boulder, CIRES, Douglas Robertson

BOULDER - A University of Colorado-Boulder study recently published online in the Journal of Geophysical Research-Biogeosciences supports the theory that a huge asteroid struck the Earth 66 million years ago, wiping out the dinosaurs and 80 percent of life on Earth.

The study, led by Douglas Robertson of the Cooperative Institute for Research in Environmental Sciences (CIRES), used models that show the collision would have vaporized huge amounts of rock that were then blown high above the Earth's atmosphere.

The reentering ejected material would have heated the upper atmosphere enough to glow red for several hours at roughly 2,700 degrees, the study said, causing a global firestorm that killed everything not underground or under water.

The firestorm also would have consumed every plant, bush and tree, leaving a charcoal layer in the geologic record around the world.

Robertson said its study confirmed there was an excess of charcoal at the time of the asteroid collision with Earth as would be expected from a global firestorm.

"Our data show the conditions back then are consistent with widespread fires across the planet," Robertson said.

In 2010, experts from 33 institutions worldwide issued a report that concluded the impact at the Chicxulub crater in Mexico's Yucatan Peninsula triggered the extinction of the dinosaurs at the Cretaceous-Paleogene, or K-Pg, geologic boundary.