For a few years, China has become the world’s largest polluter, taking the undesirable crown from the US. But according to recently released data from Chinese authorities, the country is burning out even more than previously thought – by a whopping billion tonnes more annually.

Image via Wikipedia.

Even for a country of China’s size, that’s still a massive correction, translating into 17% more coal usage than previously thought. Coming especially days before the summit in Paris, this will help put things into perspective and shed more light on what must be done if we want to achieve sustainable levels of CO2 emissions.

It also helps explain why China’s air quality is so bad. Researchers have been trying to understand and fight smog for years, with little success.

“This will have a big impact, because China has been burning so much more coal than we believed,” 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 adjustment, published without fanfare by China’s national agency, almost went under the radar. The revisions were based on a census of the economy in 2013 that exposed gaps in data collection, especially from small companies and factories.

“It’s been a confusing situation for a long time,” said Ayaka Jones, a China analyst at the U.S. Energy Information Administration in Washington.

Of course, this is big, bad news. The discrepancy is so large that it basically affects planetary scale planning. International agencies will have to re-think their prognosis, incoming regulation will likely have to be even stricter, and China especially has even more work to do. Even with this, China still emits significantly less per-capita than the US – the elephant in the room is just their huge population.

Lin Boqiang, director of the China Center for Energy Economics Research at Xiamen University in eastern China said:

“It’s created a lot of consternation,” he said. “Our basic data will have to be adjusted, and the international agencies will also have to adjust their databases. This is troublesome because many forecasts and commitments were based on the previous data.”

However, lingering somewhere at the bottom of this Pandora’s box, there is also a glimmer of hope. It shows that China, scolded for years for under-representing its pollution, is willing to at least accept its contribution. It’s a small step, but it may convince them to take even more action to fight climate change. China needs it, and so does the world.