China’s greenhouse gas emissions from fossil fuel combustion could be as much as 14 percent lower than previously thought, according to a sweeping new study released yesterday.

The study, published in the journal Nature, is considered the most accurate assessment so far of emissions levels in China. And, the authors said, while the findings don’t change China’s status as the world’s largest emitter of climate change pollution, they could have serious policy implications ahead of key U.N. negotiations in Paris.

The team, led by researchers with the University of East Anglia, Harvard University and the Chinese Academy of Sciences, re-evaluated 63 years of emissions data from the burning of fossil fuels and cement. In doing so, they reappraised the type of coal used in Chinese power plants as well as the amount of energy it generated to reveal that previous calculations had been seriously overestimated.

In 2013, China’s CO2 emissions totaled 2.49 gigatons of carbon, 14 percent less than previously thought, the authors said. Between 2000 and 2013, they calculated that China’s cumulative emissions of CO2 were 2.9 gigatons less than previously estimated—a shortfall less than the natural “sink” for carbon stored in the country’s forests.

“From a scientific perspective, we provide the most accurate data so far, the most up-to-date estimations for China,” said Dabo Guan, a professor of climate change economics at the University of East Anglia in England and a lead author of the study.

China’s fossil fuels still drive global emissions
Guan, speaking from Beijing, said he hopes the research helps spark a movement to improve emissions data in other developing countries. But he also argued that the findings should not let China off the hook on emissions goals.

“China is still the largest emitter in the world,” Guan said. “Our research doesn’t suggest China should do any less in terms of climate change mitigation, and it doesn’t change the fact that China is still the world’s largest emitter.”

The study comes as leaders from nearly 200 nations are crafting a new global climate change accord that is expected to be signed in Paris in December. As part of the deal, all countries have been asked to submit targets for tackling greenhouse gas emissions. China’s contribution is a pledge to peak its climate pollution by 2030 and to curb carbon intensity—emissions per unit of gross domestic product—60 to 65 percent below 2005 levels by 2030.

To meet those goals, the Chinese government recently released policies to cap coal consumption. According to the study, almost three-quarters of the growth in global emissions came from the burning of fossil fuels and cement production between 2010 and 2012 in China.

Guan said he started the research when, about five years ago while doing a different paper, he discovered that official national energy statistics in China were about 20 percent lower than an aggregation of provincial level statistics. In trying to figure out the gap, he discovered that coal consumption was a major contributor, but the data were unreliable.

'It’s not the end of the story’
The study adopts what it calls the “apparent consumption” approach, which is calculated by balancing domestic fuel production, international trade and other elements less subject to accounting errors. It also allows imported and domestically produced fuels to be tracked separately so that different emissions factors can be applied.

Researchers found that the total energy consumption in China was 10 percent higher between 2000 and 2012 than reported in the country’s national statistics. But when coal quality was taken into account, there was an average 40 percent drop in overall emissions from power generation and a 45 percent fall in emissions from cement-making.

Glen Peters, a senior researcher at the Center for International Climate and Environmental Research in Oslo and one of the nearly two dozen authors who worked on the study, called the 2.9 gigatons of overestimated carbon “not insignificant.” But he also cautioned that China’s emissions data will certainly be in for more changes.

He noted that China’s census, which was published after the Nature study was completed, revises energy consumption upward again by about 10 percent and coal consumption by 14 percent—potentially wiping out emissions reductions.

“It’s not the end of the story,” Peters said of the Nature study. “This should make people reflect on how emissions statistics are calculated.”

Ranping Song, who is leading the China Climate Program at the World Resources Institute, said the study highlights the need for China to strengthen its emissions data but said the government is already making efforts.

Meanwhile, he said, it’s unlikely that China will revise its Paris targets or even its negotiating tactics in light of the new numbers.

“China doesn’t see its emission action for the sake of the global environment. This is actually part of their own agenda. Those things do not go away,” Song said. “It doesn’t change their high-level commitment that doing climate-friendly development will be good for the environment and good for the economy, as well.”

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC., 202-628-6500