Sustained decrease of emissions embodied in China's international export

Known as the world factory, China emits large amounts of pollutants during production process and is facing a severe air pollution problem. However, a large portion of pollution produced in China is associated with its production of goods for foreign consumption via international trade. During the past decade, the volume of China's export is going persistent growth, yet much less known are the changes/trend of emissions embodied in international export. In addition, along with China's rapid economic growth, its economic-trade structure and volume has been changing all the time, resulting in large changes in total emissions and the shares of trade-related emissions.

By combining emission inventories with the MRIO model, we assess emissions embodied in Chinese exports in multiple years from 2007 to 2015 and find that international trade has significant impacts on China's pollutant emissions. Between 2007 and 2015, emissions embodied in international export account for 15%-21% and 9%-14% of China's total NOx and CO emissions, respectively. Most of these export-related emissions are emitted in eastern coastal areas where are densely populated, which seriously affects public health in China.

We further find that, although the volume of export itself has maintained a medium-high growth rate during recent years, emissions caused by producing export commodities have declined significantly due to the gradual maturity of Chinese production technology and the increasingly strict emission control policy. For example, export-related emission intensity decreases by 60.8%-80.4% (varies among different species) from 2007 to 2015. Correspondingly, NOx, SO₂ and primary PM_2.5 emissions embodied in export decrease by 23.4%, 61.7% and 56.6%, respectively.

Meanwhile, not only the amount of emissions embodied in export has declined, its share to Chinese total anthropogenic emissions also experiences persistent decrease. For example, the share of export-related NOx, SO₂ and primary PM_2.5 emissions to total emissions decreases from 21%, 19% and 16% in 2007 to 15%, 14% and 10% in 2015, respectively. The distinct decrease is mainly attributed to the changes of Chinese economic structure as the relative contribution of export-related output and GDP has declined from 35% and 28% to 21% and 21%, respectively, during the whole period.