The annual average spatial distribution from 2010 to 2014 derived from the relationship between ground concentration and satellite-derived AOD is shown in Fig. 2. The spatial resolution of the map is . It is seen that the highest annual average concentration is mainly concentrated in Northern China, the Sichuan Basin, and Taklimakan Desert regions, where annual average concentration is . The northwestern, the middle and lower reaches of the Yangtze River, and Inner Mongolia, Shaanxi, Shanxi, and some other provinces in northern China are as high as . In the northeastern area, Liaoning and Jilin, the annual average concentration is . In southwestern and southern China, concentration is . Over the Tibetan Plateau, Fujian and Heilongjiang province, concentration has the lowest value. In general, concentration is the highest in the northern zone, followed by the central region, and the concentration is lowest in southern China and the Tibetan Plateau.