Temporal-spatial distribution of tropospheric NO2 in China using OMI NO2 column measurements

Observations of tropospheric column densities of NO2 obtained from the satellite instruments OMI for the period of 2005 to 2010 are used to derive average monthly and seasonal variations over China. The obtained results indicate that NO2 has an imbalanced spatial distribution with the highest level in North China, Yangtze Rive Delta region and Pearl River Delta region. The seasonal pattern of the NO2 concentration shows a difference between the east and west in China. In the eastern part of China, an expected winter maximum in seasonal cycle is found. In the western part this cycle shows a NO2 maximum in summer time. The NO2 concentration shows a large growth over eastern China during the same period. Correlation analysis reveals that column densities of NO2 is the most closely correlated with coal consumption per unit area and population density.