WASHINGTON, (Reuters) – It is one of science’s enduring mysteries: what caused the worst mass extinction in Earth’s history. And, no, it is not the one that wiped out the dinosaurs.
Scientists said on Thursday that huge amounts of carbon dioxide spewed from colossal volcanic eruptions in Siberia may have turned the world’s oceans dangerously acidic 252 million years ago, helping to drive a global environmental calamity that killed most land and sea creatures.
The researchers studied rocks in the United Arab Emirates that were on the seafloor at the time and contained a detailed record of the changing ocean conditions at the end of the Permian Period.
“This is one of the few cases where we have been able to show that an ocean acidification event happened in deep time,” said University of Edinburgh geoscientist Rachel Wood, one of the researchers in the study published in the journal Science.
“This is significant because we believe our modern oceans are becoming similarly acidic,” Wood added. “These findings may help us understand the threat posed to marine life by modern-day ocean acidification.”
Various hypotheses have been offered to explain the mass extinction that exceeded even the one 65 million years ago caused by an asteroid impact that erased the dinosaurs and many other animals. The researchers said ocean acidification had long been suspected but no direct evidence had been found until now.
