We’ve officially pushed atmospheric carbon levels past their dreaded 400 parts per million. Permanently.
What’s so terrifying about this number? For several years now, scientists have been warning us that if atmospheric carbon were allowed to surpass 400 parts per million, it would mark a serious “tipping point” into some unstoppable climate ramifications. In 2012, the Arctic was the first region on Earth to cross this red line. Three years later, for the first time since scientists had begun to record them, carbon levels remained above 400 parts per million for an entire month.
