How modifications of China's energy data affect carbon mitigation targets

Frequent modifications to energy statistics have led to considerable uncertainty in China's ability to achieve its carbon mitigation targets. Here, we quantitatively measure the impact of energy data revisions on China's ability to achieve its mitigation targets. Our results indicate the following effects of data revisions: 1. Mitigation challenges have increased by 5%, and the achievement of national mitigation targets (as well as international pledges) might be postponed by two years. 2. Greater than expected carbon space or emission quota (from 22.94 to 31.31 Gt) will be obtained from 2015 to 2035. 3. CO2 peak levels may become highly uncertain, with the uncertainty varying from 12% to 29%. In addition to national mitigation targets, data revision has profound implications for key industrial sectors. For example, raw coal consumption by the cement and iron and steel industries has long been underestimated, bringing uncertainty to the achievement of industrial mitigation targets. Our results reveal considerable uncertainty in China's energy data, and this uncertainty suggests that previous mitigation achievements have been overestimated and that the mitigation targets, carbon space values, and peak level estimates proposed by future mitigation schemes may not be reached.