London: China's carbon emissions could be much lower than estimated by a UN panel of scientists, according to a leading Chinese climate change specialist.
The comments by Professor Wang Yi, director of the climate change research centre at the Chinese Academy of Sciences in Beijing, add spice to a long-running debate about the accuracy of the country's energy use data.
China is the biggest emitter of greenhouse gases, so the scale of its emissions has a critical influence on the pace of global climate change.
A study in the journal Nature Climate Change, published on Sunday, said China's carbon emissions could be nearly 20 percent greater than estimated due to discrepancies between provincial-level and national figures.
But Wang said in an interview that research being conducted by his institute pointed to the opposite conclusion.
That is because the methodology used by the Intergovernmental Panel on Climate Change (IPCC), a UN panel of climate scientists, does not take sufficient account of the big differences in calorific content of China's many grades of coal, Wang said.
"We have some preliminary calculations and current emissions may be 10-20 percent less than the result based on IPCC methodology," he said.
Even if the findings are confirmed, Wang said they would not change the bigger picture: China pumps out more carbon than any other country, about 22 percent of the global total.
"I don't think it would have much of an influence on the debate," he said.
Wang, who was speaking in London en route to a U.N. Earth summit in Rio, is working on a report with The Climate Group, a coalition of governments and companies that promotes policies and technologies to reduce global emissions.
Wu Changhua, the group's Greater China director, said better energy-use data was essential for, among other things, the development of China's proposed national carbon trading scheme.
She said China was making strides in areas such as renewable energy and clean coal but was struggling to fit together all the pieces of a strategy for sustainable economic development.
Progress on smart grids and power storage, for instance, had lagged developments in solar and wind technology.
"What China has is the political will, the belief and the desire but not necessarily all the solutions in hand," Wu said.