Satellite remote sensing of changes in NO x emissions over China during 1996-2010

Satellite derived NO2 column data have been used to study Chinese national fossil fuel consumption and pollutant emissions. Based on NO2 retrievals from two satellites (GOME and SCIAMACHY) for 1996-2010, we analyzed the characteristics and evolution of regional pollution related to NO (x) emissions in China. Satellite observations indicated that the highly polluted regions were expanding. Anthropogenic emission dominated areas have expanded from the east to central and western China, and new highly polluted regions have formed throughout the nation. Bottom-up emission estimates suggested a 133% increase in anthropogenic NO (x) emissions in East Central China during 1996 to 2010, which was lower than the 184% increase of the NO2 columns measured by the satellites. We found that growth rates of NO (x) emissions have slowed in Chinese megacities over recent years, in contrast to which, the NO (x) emissions were soaring in medium-sized cities, indicating that strict controls of NO (x) emissions from coal-fired facilities are required in China.