Perhaps the most famous thing about dinosaurs is the giant space rock that supposedly killed them. Also known as the Chicxulub impact, or K-Pg event, most people are familiar with the massive impact that occurred about 66 million years ago after a comet or asteroid collided with Earth.
It was one of the most violent cataclysms in Earth’s entire 4 billion year history. The impact was so massive that it killed about 60 percent of all marine life, all non-avian dinosaurs, and most four-legged animals weighing more than 25 kilograms (55 pounds). It was massively destructive, but in the process, the K-Pg incident paved the way for the evolution of modern life forms, including us humans.
The sulfur released…reached up to 1800 ppm and, remarkably, occurred just before the K-Pg event (within 100,000 years).
At least, that’s the story most of us have been taught for generations. But the truth may actually be more complicated.according to recent research The journal Science Advances says climate change may also have played a big role in the extinction of dinosaurs.
The scientists behind the paper determined this by studying the Deccan Traps in western India, which were formed by molten lava after a massive volcanic eruption 66 million years ago. They wanted to know how much fluorine and sulfur was released into the atmosphere when a volcano ejected one million cubic meters of rock.
After developing new scientific methods to analyze this, researchers found that the amount of fluorine released by these eruptions ranged from 400 to 3000 ppm, causing fundamental damage to the local environment rather than the entire planet. It was decided that it was sufficient to change it to . The same cannot be said for the emitted sulfur, whose concentrations reached up to 1800 ppm and, in particular, occurred just before the K-Pg event (within 100,000 years).
“Our data show that volcanic sulfur degassing from such activities caused repeated short-term global temperature declines and stressed ecosystems long before the bolide struck its final blow at the end of the Cretaceous. “This suggests the possibility that it may have provided
If future research confirms this conclusion, it could shake the foundations of how humans understand Earth’s ancient history. Rather than imagine that the K-Pg extinction was caused specifically by a giant object that crashed into our planet, the new findings paint a different picture. The idea is that volcanic eruptions caused major climate changes, which were then made worse by the devastating effects of large earthquakes. an asteroid or a comet.
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“Volcanic sulfur degassing from such activity could have caused repeated short-term global temperature declines.”
Professor Don Baker from McGill University, a co-author of the paper, said: “Our study shows that volcanic winters may have lasted for decades before the dinosaurs became extinct, and climatic conditions are almost certainly uncertain. “It shows that it was stable.” statement. “This instability would have made life difficult for all plants and animals and would have set the stage for the dinosaur extinction event. Our research therefore supports this critical event that led to the rise of mammals and the evolution of our species. It helps explain the extinction event.”
After all, scientists have long recognized the role volcanoes play in changing the climate. Some scientists hypothesize that the so-called Little Ice Age (a period of significant cooling that occurred in the Middle Ages) occurred as a result of a cluster of large, successive volcanic eruptions. This type of climate change is natural, in contrast to anthropogenic climate change, which is caused by the burning of fossil fuels.
“On human timescales (from a few years to hundreds of thousands of years), most volcanic eruptions have a net cooling effect on the climate,” said Yves Moussallam, assistant professor of Earth and Environmental Sciences and Geochemistry at the Columbia Climate School. the doctor said. I hosted a salon via email earlier this year. “This is because of sulfur dioxide, another gas emitted by volcanoes, which has increased in the atmosphere,” Mussallam said, citing the global cooling periods that occurred after the 1815 eruption of Tambora and the 1991 eruption of Mount Pinatubo. “SO2 turns into H2SO4 (sulfuric acid), which condenses.” It becomes small droplets (aerosol). Once these are injected into the stratosphere, they remain there for months or years, reflecting some of the sun’s radiation and having a net cooling effect on the Earth’s surface. ”
In his recent book, Our Fragile Moment, Dr. Michael E. Mann, a professor of earth and environmental science at the University of Pennsylvania, details how the history of life on Earth is inextricably linked to climate change. This includes, but is not limited to, volcanic eruptions.
“Life on Earth has existed for four billion years, and the environment has remained hospitable to life for billions of years, and life is playing an increasingly important role in the climate itself.” Mann said at Salon earlier this year. These include Snowball Earth, a theoretical period during which much or all of the Earth’s surface froze, as well as the mass extinction event and his K-Pg event that changed the climate from 250 million years ago. Masu. “Then, if you zoom in just a few million years ago, you have primates. There’s climate change at every step, and climate is affecting life,” Mann noted.
At the same time, it is important to note that while volcanic eruptions may have contributed to climate change when dinosaurs roamed the Earth, that does not mean that volcanic activity is the cause of modern climate change. It is important. This claim, made by many climate change deniers, is not supported by science.
” fossil fuel combustion “Cement manufacturing releases 37 Gt (billion tons) of CO2 into the atmosphere annually,” Musallam explained. “Volcanoes are estimated to contribute between 0.28 and 0.36 Gt of CO2 per year to atmospheric and oceanic systems worldwide.” Volcanoes therefore contribute about 100 times less CO2 than anthropogenic activities. is. ”
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