Scientists from McGill University in Montreal discovered that the cause of death of dinosaurs was not only a meteorite falling to Earth, but also massive volcanic eruptions that changed the Earth’s climate.
Study author Professor Don Baker presented the results of his paper entitled “Recurring volcanic winters during the latest Cretaceous: sulfur and fluorine reserves in Deccan lava.” This work suggests a link between volcanic activity and the extinction of dinosaurs.
Earth’s atmosphere underwent toxic changes 66 million years ago, caused not only by an asteroid collision, but also by massive volcanic eruptions. Analysis of the sulfur content showed that before the asteroid impact, volcanic activity and mercury were already significantly affecting the planet’s climate.
Research by geologist Sarah Callegaro of the University of Oslo suggests that the formation of sulfur lava in western India coincides with climate change. The new data contradicts previous opinions and confirms that volcanism in the Deccan Traps significantly affected the climate before the disaster.
Although basalts in the region do not typically contain much sulfur, the slow release of the cooling molecule into the atmosphere after an eruption suggests a possible cause of the global temperature drop. This resulted in periodic temperature drops of up to 10°C, followed by recovery during the 100,000 years before the asteroid impact.
“Our research shows that climatic conditions were almost certainly unstable, with repeated volcanic winters that could have lasted decades, before the extinction of the dinosaurs,” explains geochemist Don Baker of McGill University.
“This instability would have made life difficult for all plants and animals and set the stage for the extinction of dinosaurs.”
The argument for eruptions seems to be piling up, and volcanoes are, after all, the cause of the end of three-quarters of all life on Earth during the previous mass extinction.
“The Deccan Traps volcanism set the stage for a global biotic crisis, repeatedly deteriorating environmental conditions by forcing recurring short volcanic winters,” the team concludes.
Their research was published in Scientific progress.
