Carbon dioxide, methane, nitrous oxide and halogenated greenhouse gases are also covered in the China Meteorological Administration report, which found that many had reached record levels.

If the world tries to control the global average temperature rise within 2 C, scientists estimate that carbon dioxide levels should be no more than 450 ppm.

The record-high levels of greenhouse gases have caused concern among some climate experts about the country's current economic modes: fast industrialization and modernization.

"The problem is not the shocking numbers, but how to deal with them after we know," said Li Shuo, a climate and energy expert at Greenpeace, adding that greenhouse gas is a global issue, not a regional one.

"There is a really big gap between the benchmark that science indicates nature can bear and the increasing demand required by economic development," Li said.

The WMO estimated that 375 billion metric tons of carbon has been released into the atmosphere since 1750, about half of which still exists in the atmosphere.

Labeled as one of the world's largest sources of greenhouse gas emissions, China is making great efforts to cut emissions, said Qi Ye, director of the Climate Policy Initiative at Tsinghua University.

The 12th Five-Year Plan (2011-15) aims to reduce the amount of carbon emitted per unit of gross domestic product by 17 percent by 2015, compared with 2010 levels.

"China is adjusting its energy structure by using more clean energy," Qi said.

According to the State Electricity Regulatory Commission, China's electricity generated by clean energy reached 74.8 billion kilowatt hours in November, with a year-on-year increase of 20.3 percent.