BEIJING — China, the world’s leading emitter of greenhouse gases from coal, is burning far more annually than previously thought, according to new government data. The finding could vastly complicate the already difficult efforts to limit global warming.
Even for a country of China’s size and opacity, the scale of the correction is immense. China has been consuming as much as 17 percent more coal each year than reported, according to the new government figures. By some initial estimates, that could translate to almost a billion more tons of carbon dioxide released into the atmosphere annually in recent years, more than all of Germany emits from fossil fuels.
Officials from around the world will have to come to grips with the new figures when they gather in Paris this month to negotiate an international framework for curtailing greenhouse-gas pollution. The data also pose a challenge for scientists who are trying to reduce China’s smog, which often bathes whole regions in acrid, unhealthy haze.
The Chinese government has promised to halt the growth of its emissions of carbon dioxide, the main greenhouse pollutant from coal and other fossil fuels, by 2030. The new data suggest that the task of meeting that deadline by reducing China’s dependence on coal will be more daunting and urgent than expected, said Yang Fuqiang, a former energy official in China who now advises the Natural Resources Defense Council.
“This will have a big impact, because China has been burning so much more coal than we believed,” Mr. Yang said. “It turns out that it was an even bigger emitter than we imagined. This helps to explain why China’s air quality is so poor, and that will make it easier to get national leaders to take this seriously.”
The adjusted data, which appeared recently in an energy statistics yearbook published without fanfare by China’s statistical agency, show that coal consumption has been underestimated since 2000, and particularly in recent years. The revisions were based on a census of the economy in 2013 that exposed gaps in data collection, especially from small companies and factories.
Illustrating the scale of the revision, the new figures add about 600 million tons to China’s coal consumption in 2012 — an amount equivalent to more than 70 percent of the total coal used annually by the United States.
“It’s been a confusing situation for a long time,” said Ayaka Jones, a China analyst at the United States Energy Information Administration in Washington. She said the new data vindicated her earlier analysis of China’s preliminary statistics, which flagged significantly increased numbers for coal use and overall energy consumption.
The new data indicated that much of the change came from heavy industry — including plants that produce coal chemicals and cement, as well as those using coking coal, which goes to make steel, Ms. Jones said. The correction for coal use in electric power generation was much smaller.
Officials accepted the need to correct worsening distortions in the old data but have not commented publicly on the changes, according to Lin Boqiang, director of the China Center for Energy Economics Research at Xiamen University in eastern China. Mr. Lin said in a telephone interview that this was partly because the new figures made it more complicated to set and assess the country’s clean-energy goals.