The World Agreed to Slow Global Warming But the Numbers Don’t Add Up

The Paris Accords outlined a plan to curb a rise in the global average temperature – but the United Nations says even countries’ most ambitious plans may not be enough.

By Alexandra HartNovember 7, 2016 11:45 am|

In case you missed it – Friday marked an historic moment in the push to deal with climate change, when the Paris climate agreement took legal force.

Now, the rubber meets the road in Marrakech as signatories come up with ways to turn the agreement into real steps of action. But do the agreed-upon numbers add up?

Chris Mooney, who reports on science and the environment for the Washington Post, says they do not. 

“The world is taking a lot of steps to address climate change, more than it has in history,” he says. “The problem is the current promises that all the countries have made summed together do not equal anything like the path that the countries themselves say they need to be on.”

Every country came up with its own plan, Mooney says, to keep the rise in global average temperature to around 1.5 degrees Celsius.

“Unfortunately what everybody committed to do is not adequate,” he says, “and it would take us to something more like 3 [degrees Celsius]. So clearly the world has to do more and it has to do it fast. Because the United Nations also found if it doesn’t do a lot more by 2020, [the goal of] 1.5 degrees Celsius might already be gone.”

The carbon budget says, in order to have a two-thirds chance, or around 67 percent, of staying below 2 degrees Celsius, then we can only emit a trillion tons (or 1,000 billion tons) of carbon dioxide total from 2011 onward. That’s five years ago and we’ve emitted 150 billion tons already, so in our carbon budget, we have 850 billion tons left.

“The world’s doing something like 35 of them a year,” he says. “So you just start adding it up, which means every three years you get almost another hundred. That’s kind of the problem. And once it’s in the atmosphere, it stays there for a long time.”

Currently the global is on a path that’s something more like 3 degrees Celsius. “That’s way better than 5 degrees,” he says, “so we definitely want to be doing something.”

If renewables do become a major source of energy, Mooney says, we can alter this 3-degree trajectory.

“If clean energy really takes off, it’s still possible to bend the curve down and get 2 degrees,” he says. “It’s just that with every passing year, without raising ambitions even further, it becomes more difficult.”

Post by Hannah McBride.