Inventories and distribution characteristics of NO_x emissions in China

NO_x emissions change in China for nearly so years past was estimated on the basis of historical energy consumption state and NO_x emission factors. Moreover, NO_x emission inventories and characteristics in different provinces, economic sectors and fuel types from 1995 to 1998 were discussed in detail. Total NO_x emissions had increased rapidly from 4.76Mt in 1980 to 12.0Mt in 1996. Since then, NO_x emissions began to decrease somewhat, and compared with the peak value in 1996, the total emissions in 1998 had decreased about 0.82Mt. Constant imbalance distribution existed all over: more than 70 percent of the total NO_x came from coal combustion, more than about 90 percent of the total came from industry, electric power and transportation sectors, and the share of transportation raised steadily with 10.4% in 1995 increased rapidly to 13.0% in 1998; NO_x emissions in Hebei, Liaoning, Jiangsu, Shandong, Henan and Guangdong exceeded 0.5Mt, while those in Ningxia, Qinghai and Hainan were lower than 0.1Mt.