There has been a debate amongst scientists on what exactly caused the planet to become uninhabitable for dinosaurs millions of years ago. One team believes that a giant asteroid struck the Earth off the coast of Mexico 66 million years ago and caused the demise of all dinosaur species except birds. However, some researchers believed that large volcanic corruptions might have been the actual cause of the extinction event that killed 75% of life on Earth.
Researchers from UCL, Imperial College London, and the University of Bristol have completed a new study showing that only the asteroid impact could have created conditions that were unfavorable for dinosaurs around the globe. According to the study, massive volcanism could have helped life to recover from the asteroid strike in the long term thanks to global warming potential.
The team’s study shows that the asteroid caused an impact winter that lasted for decades and that the environmental effects decimated suitable environments for dinosaurs. The effects of intense volcanic eruptions weren’t strong enough to substantially disrupt global ecosystems. The researchers say that their study for the first time quantitatively shows that the only plausible explanation for the extinction is the impact winter eradicating dinosaur habitats globally.
The asteroid strike would’ve released particles and gases high into the atmosphere blocking the sun for years and causing permanent winters. However, volcanic eruptions also produced particles and gases with sun-blocking effects. Around the time of the mass extinction, there were tens of thousands of years of volcanic eruptions at the Deccan Traps in present-day India.
In the new paper, the team combined traditional geological markers for climate and mathematical models. The combination gave information about what kinds of environmental factors like rainfall and temperature dinosaurs needed to survive. They then mapped where those conditions would exist in a world after either an asteroid strike or massive volcanism and found that only the asteroid strike wiped out all potential dinosaur habitats. The volcanic eruptions left some viable regions around the equator.