Small, Surprising Dip In World's Carbon Emissions Traced To China

Dec 7, 2015
Originally published on December 8, 2015 3:46 pm

So far, the international climate meeting in Paris has primarily been about words, as diplomats wrestle with the precise language of a treaty. But some surprising climate science was unveiled this week, too — a new measurement of carbon dioxide emissions into the atmosphere that suggests the world's production of the globe-warming gas has taken a small dip.

Since the 1960s, scientists have tracked what's been an almost inexorable rise in the amount of CO2 in our atmosphere. It's the main contributor to global warming, so more CO2 means more warming.

Last year, however, that rise apparently flattened out. And this year, CO2 emissions around the world actually seem to have dropped slightly, according to a paper published Monday in the journal Nature Climate Change.

Climate scientist Rob Jackson from Stanford University says it's a small dip — less than 1 percent. Still, even that amount is significant. As economies surge they usually use more energy, Jackson says, which means they put out more CO2. But that's not what happened this year.

"I was surprised by the result," he says. "Previously we've only seen this sort of thing when global economies were in crisis. That's the most exciting piece of this puzzle: We're seeing a flattening or decline in emissions at a time when the global economy is still growing robustly."

Jackson and an international team used data from the Global Carbon Project, which tracks worldwide CO2 emissions, to come up with their result.

Climate scientist Corinne Le Quere from the University of East Anglia, in the United Kingdom, says there's one main reason for the good news: "It's mostly down to China's use of coal," she says.

China burns an enormous amount of coal — creating an enormous amount of CO2. But as China has started to deal with its air pollution problem, and the country's economic growth has slowed, "all of a sudden, it looks like their use of coal in 2015 actually has gone down," Le Quere says.

And China's CO2 emissions have, consequently, dropped a startling 4 percent this year.

Worldwide, the total decline in emissions is much less — less than 1 percent. Still, it reverses a relentless increase the world has experienced over the past few years.

The team notes in the published report that emissions from Western Europe and the U.S. have also flattened out. That's largely because of an increase in the amount of power coming from solar, wind and natural gas — instead of coal — in the U.S.

But Le Quere says it's China, the world's biggest source of CO2, that will drive the ups and downs in the emissions numbers for the world in the near future. And no one should expect the downturn from China to last.

"Whether the emissions are going to pick up again in China? I certainly think they will," Le Quere says, because China's economy is bound to revive. Also, it's worth remembering that the findings are based on emissions reports from China — which have not always been accurate.

But John Holdren, the science adviser to the White House, says whether the decline is a blip or more lasting, it suggests that a real decline in emissions is within reach.

"The global total should absolutely be going down after 2020," Holdren says, "so what we are seeing now is a good sign and should not be regarded as cause for false hope, but cause for real hope that the world is turning this around." Still, he says, "we'll need to do much more."

The need is great because India will soon be the world's biggest source of CO2 instead of China, as India embraces coal to bring electricity to hundreds of millions of its citizens.

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ARI SHAPIRO, HOST:

Now, this climate meeting is mostly an affair for diplomats fighting over the wording of an international treaty. But yesterday, a team of scientists unveiled something new that took a lot of people here by surprise. NPR's Christopher Joyce is here in Paris covering the summit with me and has this report.

CHRISTOPHER JOYCE, BYLINE: Since the 1960s, scientists have tracked what's been an almost inexorable rise in the amount of carbon dioxide in our atmosphere. CO2 is the main greenhouse gas that causes warming, so more CO2 means more warming. Last year, however, that rise apparently flattened out, and this year, CO2 emissions around the world actually dipped. Climate scientist Rob Jackson from Stanford University says it's a small dip - less than 1 percent - but it's significant.

ROB JACKSON: I was surprised by the result. Previously, we've only seen this sort of thing when global economies were in crisis. That's the most exciting piece of this puzzle. We're seeing a flattening or a decline in emissions at a time when the global economy is still growing robustly.

JOYCE: Usually when economies are doing well, they're using more energy and putting out more CO2. Jackson and an international team used data from the Global Carbon Project, which tracks worldwide CO2 emissions. Climate scientist Corinne Le Quere from the University of East Anglia in the United Kingdom says there's one main reason for the good news.

CORINNE LE QUERE: It's mostly down to China's use of coal.

JOYCE: China burns an enormous amount of coal, and that creates an enormous amount of CO2.

LE QUERE: And now China's economic growth has slowed down. They have done massive measures to deal with their problem of air pollution. And all of a sudden, well, it looks like their use of coal in 2015 has actually gone down.

JOYCE: That's lowered China's CO2 emissions a startling 4 percent this year. Worldwide, a total decline is less than that - less than 1 percent. It's not much, but it reverses a relentless increase over the past few years. Writing in the journal Nature Climate Science, the team also notes that the emissions from Western Europe and the U.S. have also flattened out. That's largely due to a lot more solar and wind power and natural gas replacing coal in the U.S.

But Le Quere says it's China, the world's biggest source of CO2, that will drive the ups and downs in the admissions numbers for the world. And she says people should not expect the downturn to last.

LE QUERE: From now, whether the emissions are going to pick up again in China, I certainly think they will.

JOYCE: Because, she says, China's economy will probably revive. Moreover, the researchers say the findings are based on emissions reports from China, which have not always been accurate. But John Holdren, the science adviser to the White House, says whether the decline is a blip or more permanent, it suggests that a real decline in emissions is within reach.

JOHN HOLDREN: The global total should absolutely be going down after 2020. So what we are seeing now is a good sign, and it should not be regarded as cause for false hope. It should be regarded as cause for real hope that the world is turning this around. But we'll need to do much more.

JOYCE: That's because India will soon be the world's biggest source of CO2 instead of China, as it embraces coal to bring electricity to hundreds of millions of its citizens. Christopher Joyce, NPR News, Paris. Transcript provided by NPR, Copyright NPR.