Washington: The mass extinction of half of Earth’s marine life over 200 million years ago was thought to have been caused by a destructive wave of volcanic activity.
But scientists have now claimed that a giant, deadly “Earth burp” of methane emitted hundreds of millions of years ago might have caused the extinction.
Micha Ruhl and researchers from the Nordic Center for Earth Evolution at the University of Copenhagen in Denmark have found that the mass extinction was likely the result of the giant release of carbon methane in the atmosphere.
This massive methane “burp” led to an increase in atmospheric temperature around the globe -- and organisms and ecosystems were simply unable adapt to their hotter environment.
“We measured the isotopes of carbon in plants, from before the mass extinction event and then after the mass extinction,” Ruhl told FoxNews.
“We found two different types of carbons and the molecules that were produced during that event.
“So we started thinking of other sources of carbon that could have changed the atmosphere,” he stated
Extensive calculations and research by his team revealed that the burp pumped over 12,000 gigatons of methane into the atmosphere during the final years of the Triassic.
While volcanism was revealed not to have caused the extinction itself, the researchers believe that the volcanoes indirectly set the events in motion by triggering the methane release.
“A small release of carbon dioxide from volcanism initiated global warming of the atmosphere, increasing temperatures in the oceans,” Ruhl said.
“Methane is stored in the sea floor -- it’s a molecule which is caught in some kind of ice structure. As soon as the temperatures got above a certain threshold, the ice melted and that methane was released,” he added.
First Published: Friday, July 22, 2011, 15:56