New research challenges dinosaur extinction cooling theory
Seventy-five percent of life on Earth was destroyed after the asteroid impact at Chicxulub, which occurred 66 million years ago. Until now, scientists have proposed various theories about the cause of this extinction, including that of the dinosaurs. However, new research is emerging.
Scientists frequently referenced the theory that Earth experienced radical and prolonged cooling. After the asteroid impact, a large amount of sulfur was supposed to have been released into the atmosphere, negatively affecting the temperature.
What really killed the dinosaurs?
It now appears, however, that these assumptions may have been exaggerated. The latest research is based on an analysis of drill cores taken from the Chicxulub impact site. Scientists estimated how much sulfur was actually released into the atmosphere.
The number is impressive—about 74 billion tons of sulfur. Although this is a truly astronomical amount, it is five times lower than previously thought.
The Earth got colder, but not so much that life couldn't survive
It seems that 25% of Earth's species may have survived because the climate cooling wasn't as intense. The smaller amount of sulfur compared to previous assumptions means the "cold and dark" atmosphere did not persist for as long. The return to normal climatic conditions happened quicker than previously assumed.
Nonetheless, the release of sulfur into the atmosphere as a result of the asteroid impact contributed to the mass extinction of species. This happened because the impact occurred in an area where the rocks were rich in sulfates. In the latest research, scientists used a method of sulfur isotope analysis. They compared data with the Cretaceous-Paleogene boundary layer. The results of the study may also be useful to other scientists studying phenomena related to mass extinctions from 66 million years ago.
The new discovery also shows that life on Earth had a greater chance of survival than previously assumed, which may affect the way other mass extinction events are interpreted.
