2 Degrees In Paris: The Global Warming Set To Dominate Climate Conversation

Transcript

MICHEL MARTIN: Climate change is being addressed this week in Paris. World leaders will meet at the U.N. Climate Change Conference and work on policies aimed at slowing the Earth's rising temperature. And that brings us to our weekly feature Words You'll Hear. That's where we try to understand stories we'll be hearing more about in the coming days by parsing some of the words associated with those stories. This week, it's a phrase expected to dominate climate change talks - two degrees. Joining us to tell us more about this is NPR's science correspondent Christopher Joyce. Hi, Chris.

CHRISTOPHER JOYCE, BYLINE: Hi, Michel.

MARTIN: So what do you mean by two degrees when it comes to climate change?

JOYCE: It's two degrees - and that's Celsius, by the way, which is about three and a half degrees Fahrenheit. Two degrees is a target. The climate negotiators in Paris are using that target as a basis, frankly, for trying to change the way that the world makes energy - the whole energy economy. They're saying that the planet can only take so much warming. And it's already warmed about one degree since about 1900, when the Industrial Revolution really got rolling. And scientists say that this warming is caused primarily by burning oil, coal, natural gas, fossil fuels and cutting down and burning forests. And they say, OK, one degree's bad, but two degrees is really bad, and that's when you're going to serious consequences.

MARTIN: Gosh, I hate to go there, but I have to go there. What happens if temperatures rise more than this average two degrees.

JOYCE: Well, not good. How much not good? Nobody really knows for sure. It's kind of strange that the number was sort of put forward by an economist in the '70s simply as an arguing point, sort of. Is there a tipping point when climate warms enough so we see really serious damages? But scientists are pretty assured that we will see more severe weather, more droughts, heat waves. Some of these things we're seeing now. Certainly we're seeing sea level rise as glaciers and ice sheets in the Antarctic and in Greenland start to melt. How much more will happen? Nobody knows exactly how much we can go above two degrees before we see really serious stuff.

MARTIN: So why are these talks different? Or are they different from the talks that have gone on before? I think a lot of people will remember the countries have been talking about climate change for quite some time. How are these different?

JOYCE: Well, in the past, the Kyoto Treaty - the only one we've ever had - that required countries - it gave them targets to reduce their emissions of greenhouse gases, and they were set by the U.N. That really didn't work. And so this time now, each country comes forward with its own amount that they'll reduce emissions. They pick their own number, and its voluntary. It's not mandatory. There's no punishment if they don't make it. The other thing that's different is that the developing world is now part of this whole process. Under the Kyoto treaty, it was only the developed world that had to cut its emissions. This time, everybody is in - every country from Cuba to the United States to the Seychelle Islands.

MARTIN: So do they have to come up with a plan to keep us below two degrees of warming? And who's going to decide that?

JOYCE: Right, and that's where the two degree target comes in. The idea is that when all of these countries come forward, as they are now this week, their pledges to reduce greenhouse emissions - you put it into a computer. And you say, OK, is that enough to keep us below a two degree increase? And frankly, so far, it's not. What do we do? And the plan is, well, we're going to ask people to come back every five years after the Paris meeting and keep ratcheting down our emissions to try to get us from going above that two degree mark.

MARTIN: That's NPR's Chris Joyce. He'll be following the U.N. Climate Change Conference, which starts in Paris on Monday. Thanks, Chris.

JOYCE: My pleasure. Transcript provided by NPR, Copyright NPR.