China’s carbon emission overestimation may be larger than land carbon sink

It seems that level of carbon emissions in China has been significantly overestimated. According to a study published in the popular science journal Nature, the current CO2 calculations were done using a globally averaged formula. However, when researchers carried out tests for finding out the actual coal types getting burned in Chinese power stations, they came to know that the carbon produced by them was 40% less than what was previously assumed.

The results put forward by the study are suggesting that the error constituted 10% of global emissions for the year 2013.

With rapid economic growth during the last one and half decade, China has also witnessed significant increase in the amount of coal burnt for energy production. Statistics obtained in 2006 suggest that the country has had one and half new coal power stations built every week on average.


It’s true that the rate of growth is no more that high, but such extreme dependence on coal automatically made China the country emitting maximum carbon dioxide. For the first time ever, it topped the list of countries emitting maximum CO2 in the year 2007. Since then it has successfully retained its position at the top of the list.

The researchers began this study with the aim of clearing their doubt on the exact level of carbon getting emitted into the atmosphere from these Chinese power stations. Although the country publishes energy statistics at regular intervals, it never presents routine information about carbon emissions.

International organizations try to put forward accurate carbon dioxide estimations by using customary emission factors and energy data. This provides scientists with information on the amount of carbon emitted from burnt fuel. These emission factors presented by the IPCC (Intergovernmental Panel on Climate Change) are usually calculated based on assumptions about coal types being used in different power stations in China. This allows researchers to carry out global comparisons.

During this new study, researchers conducted the entire process differently. They checked the carbon content of more than 4,000 Chinese coal mines separately and also analyzed laboratory tests of as many as 602 coal samples. These fresh tests showed that the emission factors were around 40% less compared to the default value put forward by international organizations such as the IPCC.