“This is the first time in human history our planet’s atmosphere has had more than 415 ppm CO2,” tweeted meteorologist Eric Holthaus, after promptly picking up on the news. “Not just in recorded history, not just since the invention of agriculture 10,000 years ago. Since before modern humans existed millions of years ago. We don’t know a planet like this.”
As a point of reference, 350 ppm is a concentration that experts consider safe – the international environmental organization 350.org even dedicates its name to such effect.
If carbon emissions continue unabated, they are expected to drive up global temperatures at the same time. But something of an unknown is what effect this will have on the planet. Scientists warn that an increase of 2° C (3.6° F) above pre-industrial levels would limit the severity of more intense storms, flooding, sea-level rise and the loss of agriculture and ecosystems. The bad news is we are currently on track to go far beyond that.
Read more at New Atlas