Abstract: In this study, the routine environmental monitoring of pollutant concentration data, NCEP/NCAR 0.5°×0.5° reanalysis data and conventional meteorological observation data were used. The purpose of the study was to lucubrate the air pollution process of a strong sandstorm in 13 provinces (including autonomous regions and municipalities directly under the central government) in China from May 3 to 6, 2017. The results showed that the average daily concentration of PM₁₀ in the main cities suffering from the sandstorm was increased by 2-10 times relative to the monthly average. The average daily concentration of PM_2.5 was increased by 5~8 times relative to the monthly average concentration. During the intense sandstorm, the concentration of particulate matter was in a clear upward trend, and the increase of PM10 concentration was more obvious than that of PM2.5, which indicated that the sandstorm carried a large amount of coarse particle pollutants. On the contrary, during the occurrence of sandstorm, the average daily concentrations of SO2, CO and NO2 were in a decrease trend, which revealed that the sandstorm had a certain effect of diffusing O₃. In addition, the locations of the regions with low visibility, high PM₁₀ concentration and 3 h positive pressure were basically accorded with and located in the rear of ground cold front, which could provide a synoptic basis for predicting and preventing sandstorm and its pollution.

Key words: dust storm, inhalable particles (PM10 and PM2.5), circulation feature, gaseous pollutants (SO2, CO and NO2)