Emission inventory and trends of NO x for China, 2000–2020

The rapid growth of NO x emissions in China is mainly due to intensive fossil fuel consumption. In order to control NO x emissions, a multiyear NO x emission inventory was established by a bottom-up approach for the period 2000–2010. The results showed that NO x emissions increased by 2.1 times from 11.81 million tons (Mt) in 2000 to 24.33 Mt in 2010. We found that NO x emissions had exceeded SO 2 emissions in 2009 by comparison with their emission trends. We also found that the unbalanced NO x emissions in Eastern China and Western China are mainly due to the different gross regional product and industrial structure. Accounting for 70% of total energy consumption in China, coal is the largest NO x emission source among all the fossil fuels. In addition, the increased use of diesel and gasoline has spurred the increase of NO x emissions from the transportation sector. Manufacturing, electricity production, and transportation together composed about 90% of the national NO x emissions. Meanwhile, energy consumption and NO x emissions in China are predicted to be 3908.5 Mt standard coal equivalent (SCE) and 19.7 Mt in 2020 with this scenario analysis, respectively. To achieve a desired NO x reduction target, China should take strict measures to control NO x emissions, such as improvement in reduction technology, promulgation of new emission standards, and joint control by various Chinese provinces.