(Image credit: NASA/JPL-Caltech) (opens in new tab) Dark daysįor the research presented at the AGU conference, scientists modeled the effects of long-term darkness by reconstructing ecological communities that would have existed at the time of the asteroid impact. Scientists think that a giant asteroid, which broke up long ago in the main asteroid belt between Mars and Jupiter, eventually made its way to Earth and led to the extinction of the dinosaurs. This artist's concept shows a broken-up asteroid. "The concentration of soot within the first several days to weeks of the fires would have been high enough to reduce the amount of incoming sunlight to a level low enough to prevent photosynthesis." "The common thinking now is that global wildfires would have been the main source of fine soot that would have been suspended into the upper atmosphere," Roopnarine said.
However, it's only in the past decade or so that researchers developed models showing how that darkness may have impacted life, Roopnarine told Live Science in an email. Clouds of pulverized rock and sulfuric acid from the crash would have darkened skies, cooled global temperatures, produced acid rain and sparked wildfires, Live Science previously reported (opens in new tab). Scientists first proposed the post-asteroid "nuclear winter scenario" in the 1980s this hypothesis suggested that darkness played a part in the mass extinctions after the Cretaceous impact, said Peter Roopnarine, a curator of geology in the Department of Invertebrate Zoology and Geology at California Academy of Sciences, and a presenter at the AGU meeting.
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