Earth is already on track to mirror one of the biggest mass extinction events in history due to the rapid global warming.

A new study compared the current conditions of the modern world to the events that triggered "the Great Dying" that occurred 252 million years ago and marked the end of the Perman geologic period. It remains to be seen how many species exactly perished after the catastrophe and what caused it, but fossil records revealed that it is the single greatest calamity on Earth.

History Repeating Itself

"It was a huge event," said Curtis Deutsch, co-author of a new study. "In the last half a billion years of life on the planet, it was the worst extinction."

The "Great Dying" wiped out 96 percent of all marine species and about two-thirds of terrestrial species. The event was worse than the giant asteroid impact, which caused the extinction of dinosaurs 65 million years ago.

To this day, scientists still do not know what event caused the global catastrophe. Some believe that major might have triggered the mass extinction.

However, in a new study published in the journal Science, Deutsch and colleagues identified that rising temperatures and oxygen depletion were to blame for the mass extinction. Scientists from Stanford and Washington University used paleoceanographic records to build a model and analyze changes in animal metabolism and the conditions of the ocean and climate millions of years ago.

The models revealed that the greenhouse gases ejected from volcanic eruptions caused the planet to significantly warm. This also caused oxygen from the ocean to be depleted, leaving marine animals gasping for breath. When the period experienced its hottest global temperature, 80 percent of the oxygen in the oceans have been depleted and most marine animals have gone extinct.

The Next Mass Extinction

The findings of the new study are terrifying because it shows what could be Earth's future if countries could not control the emission of excess greenhouse gases into the atmosphere. The past century has seen the global temperature rise by around 1 Celsius and experts predict further warming by up to 3 Celsius by the next couple of decades due to the burning of fossil fuels.

Nearly 500 species have already perished because of human degradation and destruction of natural habitats since 1900. The World Wildlife Fund estimates that between 0.01 and 0.1 percent of all species on Earth will become extinct every year. If the low estimate that there are around 2 million different species on Earth is accurate, the world is losing between 200 and 2,000 species each year.

"We are about a 10th of the way to the Permian. Once you get to 3-4C of warming, that's a significant fraction and life in the ocean is in big trouble, to put it bluntly," Deutsch added. "There are big implications for humans' domination of the Earth and its ecosystems."