Scientists believe they have understood the falling dominoes that have led to the largest mass extinction on Earth, and are worried that climate-induced climate changes put the planet in a vaguely similar way.
About 250 million years ago, about 90% of marine life and 70% of earthly life disappeared into what is now called the Great Dying.
Scientists have long speculated that massive volcanic eruptions have triggered the cataclysmic event, but what has been done is still a bit fuzzy.
It was not lava itself. A new study in Thursday's Science magazine uses sophisticated computer simulations to figure out what happened after the volcano erupted: This has led to an increase in ocean temperatures of about 11 degrees Celsius, which in turn has led to depletion of seawater oxygen.
This hot water, depleted by oxygen, caused the mass murder, especially away from the equator.
After the volcanoes exploded, the level of thermal carbon dioxide capture rose to a level that is more than 12 times higher than what is today, said the researcher, lead author Justin Penn, a science scientist at the University of Washington.
The water loses oxygen when it's warm, like the warm flask that gets warmer, Pen said.
Scientists have examined dozens of modern species to see what happens to them in warmer water depleted by oxygen, and that helps them understand that the past is gone.
One of the keys in the study is that more species die away from the equator. This is because tropical species are more acclimated to low levels of oxygen, Pen said.
As long as people do not warm the Earth anywhere close to what happened naturally 250 million years ago, "this puts our future in the category of contenders for a real catastrophe," says co-author Curtis Deutsch, Earth Scientist at the University of Washington.
Ancient Dying "shows almost exactly what lies at the end of the way we are," said Deutsch. "We really do the same thing about the climate and oceans on Earth."
The study estimates that if the carbon dioxide emissions continue to current levels by 2300, the globe will experience 35-50% of the extinction rate observed at the Great Death.
Paleontologist at Leeds University Paul Weingal said there would be no scenario of global warming that would be 20 degrees of warming over the next few centuries so it could turn out to be millennia.
But even an event that is 10% worse than the "Great Death" would be terrible, "said Wigallol, who was not part of the study.
Other outside scientists believe the study is scary in the future of the Earth.
"As we warm the Earth at a rapid pace, the results of this study may be very useful in understanding what is happening with life in future oceans," said Southern California University, David Bouther, in an email.