last 3 million years<\/a>, is still significantly less, at 415 ppm (but rising fast).<\/p>\nThe immense amount of greenhouse gases present back then warmed global atmospheric temperatures to levels 18 degrees Fahrenheit higher than they are today. Because of the impact this had on ecosystems, it forced land animals to rapidly adapt, move or die. Seventy percent did not make it.<\/p>\n
In the ocean, atmospheric carbon dioxide was absorbed, mixing with water and forming sulfuric acid, acidifying the seas. As a result, coral disintegrated and the shells of ocean creatures dissolved.<\/p>\n
Back on land, the hotter climate shifted vegetation and ignited fires. That exposed more rocks, and erosion went into overdrive. As a result, an overabundance of nutrients flowed into the oceans, causing at first an explosion of life. But then there was the inevitable death and decomposition, which ate up most of the life-giving oxygen in the ocean. Ninety percent of ocean life died. Brand says existence was getting hit from all angles.<\/p>\n
“These are not individual and separate causes, but they all acted together, they acted in concert, and that is why I call it the perfect storm. You got hit on this side with temperature, on this side with acidification and then finally the knock-out punch came from deoxygenation.”<\/p>\n
Learning from history<\/h3>\n
As catastrophic as the Great Dying was, scientists are concerned the Earth could now be headed for another disaster. Right now, the planet is\u00a0warming abruptly<\/a>\u00a0to levels not seen in over 100,000 years,\u00a0oceans are acidifying<\/a>\u00a0and oxygen\u00a0dead zones<\/a>\u00a0are multiplying.<\/p>\nAnd astonishingly, Brand says that the rate of release of heat-trapping greenhouse gases now is much more radical than it was back then. “Right now our emissions are 10 to 20 times higher than what happened at the end of the Permian mass extinction, which was the largest and biggest mass extinction,” he said.<\/p>\n
To save ourselves, he says we must learn from events like the Great Dying. “You know what they say, learn from history, because if you don’t you will repeat it.”<\/p>\n
“The way I see it is, it is going to happen if we don’t stop it or don’t mitigate what we are doing,” he said. But Brand stressed that we still have time to turn it around by moving away from the burning of fossil fuels.<\/p>\n<\/section>\n
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