Rapid global warming caused the largest extinction event in the Earth's history, which wiped out the vast majority of marine and terrestrial animals on the planet.
The mass extinction, known as the "great dying", occurred around 252m years ago and marked the end of the Permian geologic period. The study of sediments and fossilized creatures show the event was the single greatest calamity ever to be life on Earth, eclipsing even the extinction of the dinosaurs 65m years ago.
Up to 96% of all marine species perished while more than two-thirds of terrestrial species disappeared. The cataclysm was so severe it wiped out most of the planet's trees, insects, plants, lizards and even microbes.
Scientists have theorized causes for the extinction, such as a giant asteroid impact. But US researchers now say they have pinpointed the demise of marine life to the earth's warming.
"It was a huge event. It was the worst extinction, "said Curtis Deutsch, an oceanography expert who co-authored the research, published on Thursday, with his University of Washington colleague Justin Penn along with Stanford University scientists Jonathan Payne and Erik Sperling.
The researchers used paleoceanographic records and built a model to analyze changes in animal metabolism, ocean and climate conditions. It's a matched the extinction records.
According to the study, this suggests that marine animals essentially suffocated as warming waters. "For the first time, we said it was a whole lot of confidence that this is what happened," said Deutsch. "It's a very strong argument that rising temperatures and oxygen depletion were to blame."
Earth's temperatures increase by around 10C (18F). Oceans lost around 80% of their oxygen, with parts of the seafloor becoming completely oxygen-free. Scientists believe this warming was caused by volcanic activity.
Published in Science, found that the drop in oxygen levels was particularly deadly for marine animals living closer to the poles. "The gap" to the sea, and to "shell the gap", and to the model found, Payne said.
"He really added. "It shows up to the point where you do not survive. It took millions of years to recover from the Permian event, which is essentially from the perspective of human timescales. "
2C two to the release of greenhouse gases from the burning of fossil fuels such as coal, oil and gas, rather than from volcanic eruptions.
This warming is already causing punishing heatwaves.
"The sixth great extinction" at the same time, Earth's species are undergoing two to habitat loss, poaching, pollution and climate change.
"It does terrify me to think we are going to the trader," Payne said. "It does not look like that of biodiversity yet." But even getting halfway. We are currently experiencing is fairly large. "
Deutsch said: "We are about 10th of the way to the Permian. Once you get to 3-4C of warming, that's a big fraction, to put it bluntly. There are big implications for humans' domination of the Earth and its ecosystems. "
Deutsch added that the only way to avoid the problem of climate change in the oceans using other measures.
Pamela Grothe, a paleoclimate scientist at the University of Mary Washington, said the research group, said Pamela Grothe, a scientist at the University of Mary.
"She pasted the key to the future," she added. "Our current rates of carbon dioxide emissions is instantaneous geologically speaking and we are already seeing warming ocean temperatures and lower oxygen in many regions, currently affecting marine ecosystems.
"If we continue with the emission rates, this study highlights the potential that we can see in the Permian."