At the annual meeting of the American Geophysical Union on May 23, two UCSB scientists presented new findings suggesting that a large, extraterrestrial rock may have exploded over North America 13,000 years ago. This meteor is considered to be a possible explanation for a period of atmospheric cooling known as the “Younger Dryas.” “This is what happens when you do interdisciplinary science,” said Luann Becker, research scientist with UC Santa Barbara’s Institute of Crustal Studies. “You can solve some of the bigger problems.”
According to the scientists, wildfires resulted from the explosion of the rock, killing off the vegetation which served as a food supply for the larger mammals, which in turn led to their extinction and then that of a prehistoric Native American culture – the Clovis people – who hunted them, explained Becker.
At over a dozen archaeological sites in North America, high concentrations of iridium – an element almost exclusively associated with meteors – along with other impact tracers were found.
The team concluded that the impact of the space rock melted a large portion of the Laurentide ice sheet, causing enormous amounts of cool, fresh water to flow into the Atlantic and Arctic Oceans and cooling the atmosphere. The scientists have found evidence for this as far west as the Santa Barbara Channel Islands.
The Paleoclimate Program of the National Science Foundation and NASA funded this research.