We’re pushing Earth’s climate back to the Bygone era of the Triassic
The Triassic period featured some magnificent beasts, but you would not want to live there. Photo Credit Reference.com:
Fans of dinosaurs are familiar with the Triassic period. It ran for around 50 million years from a mass extinction of species at the end of the Permian until the dawn of the Jurassic some 200 million years ago. The Triassic featured some pretty cool dinosaurs and giant crocs, and it was a seminal period in the life of the planet.
But would you want to live there? Probably not. The trouble is, however, that we are on course to creating a climate that is very much like the one that prevailed in the Triassic. And it won’t take millions of years. A mere couple hundred years will do if we continue burning fossil fuels at the pace and intensity we are doing now, as if there was no tomorrow.
Within 200 years, we might well end up having pumped as much carbon dioxide into the atmosphere as there once was during the Triassic and has not been seen since. Add another 150 years to that timeframe, and we could have more CO2 in the atmosphere than there has ever been in the entire observable geological history of the planet.
This is according to climate scientists at the University of Southampton, in the United Kingdom, who have just published a study in the journal Nature Communications. By examining fossilized plants and other indicators of atmospheric CO2 in times past, the researchers compiled more than 1,200 estimated concentrations of carbon dioxide in ancient atmospheres. Their goal was to chart a continuous record of such concentrations over vast timescales, which they did all the way back to 420 million years ago.
“We cannot directly measure CO2 concentrations from millions of years ago,” says Gavin Foster, the study’s lead author who is professor of isotope geochemistry at the university. “Instead we rely on indirect ‘proxies’ in the rock record. In this study, we compiled all the available published data from several different types of proxy to produce a continuous record of ancient CO2 levels.”
Their finding is pretty alarming: If we carry on burning all the available fossil fuels of the planet in coming years and decades, concentrations of CO2 in the atmosphere could reach a level that has no geologically preserved equivalent during this observed 420-million year period.
Concentrations of the greenhouse gas have “fluctuated on multi-million year timescales over this period, from around 200-400 parts per million (ppm) during cold ‘icehouse’ periods to up to 3000 ppm during intervening warm ‘greenhouse’ periods,” the authors explain. Yet “the current speed of climate change is highly unusual.”
“Highly unusual” is the scientists’ way of saying “extremely dangerous and abnormal.” They elucidate: “[T]he climate today is changing at rates well above the geological norm. If humanity fails to tackle rising CO2 and burns all the readily available fossil fuel, by AD 2250 CO2 will be at around 2000 ppm – levels not seen since 200 million years ago.”
The dinosaurs of the Triassic will never come back. But their period’s climate may well do. And life on Earth will suffer the consequences.