After months of gloomy headlines from the world of climate science — melting icecaps, possible methane eruptions in the tundra, snowballs slung on the Senate floor — there was a small ray of sunshine last week.
Global carbon emissions were flat in 2014 even as the world's economy grew three percent, according to a study by the International Energy Agency. Though emissions have dipped during economic slumps, last year marked the first time in four decades that emissions didn't go up during a period of growth.
"The importance of this flattening is it's a real-world demonstration that we can have economic growth without increasing carbon pollution," David G. Hawkins, director of the climate program at the Washington-based Natural Resources Defense Council, told VICE News.
"The more challenging news is we have to do better than just flattening emissions in order to protect the climate. We actually have to start cutting global emissions by somewhere between three and five percent a year for CO2, depending on what happens to the other global warming pollutants."
And with the United Nations trying to coax members into a landmark climate pact this year, breaking the link between growth and emissions could drastically change those talks.
"The concern from day one has been the possibility that the reduction of carbon will necessarily mean a reduction in economic growth and well-being," Tom Peterson, president of the Center for Climate Strategy, told VICE News. "If that's not the case, it removes the principal barrier to enactment of carbon reduction actions. ... It rearranges this whole negotiation, so that instead of this being the avoidance of pain, it is going to be the pursuit of gain."
The biggest change occurred in China, which cut emissions slightly in 2014. The world's biggest economy and biggest carbon emitter is in the middle of a major push for renewable power sources like wind, solar, and hydroelectric. Growth slowed last year, but remained over seven percent as the nation's rapid industrialization continued.
"It demonstrates that it is possible for large countries, large industrializing countries, to slow their pollution while growing economically, and China is the best example of that," Hawkins said.
China is still heavily invested in cheap, efficient but dirty coal-fueled power plants. Beijing has built two-thirds as many in the last five years alone as US utilities have in their entire portfolio, Hawkins said — and those plants are likely to run for decades.
Since 2010, two coal plants have been shuttered for every new one opened.
But at the same time, China has agreed to an emissions peak in 2030, if not before. And Chinese investment in photovoltaic technology has driven down the price of solar power and fueled a worldwide boom in that renewable power source.
"This is not science fiction," Hawkins said. "They're doing things that rely on demonstrated technologies."
Peterson, whose organization has worked with Chinese officials to help devise low-carbon policies, said the country is working from both the top down and the bottom up to reduce emissions.
"You're literally seeing a greening of the industries that are being recruited into their industrial development zones," he said. "You're seeing a reduction in those industries that don't meet those criteria. And that's having a big effect, because the industrial emissions base in China is enormous."
Peterson said similar processes are at work in the United States, where changes in everything from local transportation policies to the national phase-out of incandescent light bulbs have helped flatten American emissions.
"None of those things alone do it," Peterson said. "It's the combination of these thing. They are dominated by the bottom-up, state and local, the sub-national stuff, but they lead to very significant federal actions as well."
Improvements in automotive mileage and utilities switching more power plants from coal to cleaner natural gas also are keeping CO2 output down. A Sierra Club report out this week found the number of coal plants shrinking in the United States and Europe, while the boom in coal-fired electricity in China and India appears to have been reversed.
Since 2010, two coal plants have been shuttered for every new one opened, the US-based environmental group found. Meanwhile, many US states now require utilities to generate a certain share of their power from renewable sources — from about five percent in Texas to 40 percent in Maine.
And in Europe, a struggling cap-and-trade system and increased reliance on renewables in Germany and Scandinavia appear to be holding the line.
"We have demonstrated that it's technologically and economically possible to do that," Hawkins said. "But without serious policies that reward people for cutting carbon pollution, it's entirely possible for this to be a temporary phenomenon."
Follow Matt Smith on Twitter: @mattsmithatl