China’s carbon emissions may be significantly lower than assumed, a study has shown, in a surprising conclusion ahead of a big climate change meeting in Paris in December.

China’s emissions have been soaring for years, surpassing those of the US and Europe as its rapidly growing economy tapped enormous reserves of coal to fuel power plants, smelters and industry. Some forecasters even expect China to lead the world in cumulative emissions, which factor in years of smoke from Europe’s industrial revolution.

The pall of smog over big cities and the thick brown or even greenish smoke from industrial plants is easy to blame on the burning of dirty, low-quality coal and even coal waste. But a study in the science journal Nature this week concludes that China’s use of lower-quality coal results in lower greenhouse gas emissions than previously thought. It estimates that 2013 emissions were 14 per cent lower than estimates by international institutes.