Fig. 1. Lidar structure diagram

Fig. 2. Flow chart of pollution analysis based on multi-source sensor data

Fig. 3. Time series of PM2.5，PM10 concentration and PM2.5/PM10

Fig. 4. Spatial-temporal variation of lidar extinction coefficient and lidar range-corrected signal and planetary boundary layer height during observation period

Fig. 5. The 48 h backward trajectory by HYSPLIT during the pollution period

Fig. 6. Time series of PM2.5_{concentration in Zhengzhou and Baoding on January 11-14，2015}

Fig. 7. MODIS remote sensing true color image （UTC time）

Fig. 8. The 550 nm AOD observed by MODIS remote sensing （UTC time）

Fig. 9. Total backscatter coefficient，vertical feature mask，and aerosol subtype observed during CALIPSO transits over Beijing

Fig. 10. PM2.5 concentration and ground meteorological parameters on January 11-17，2015

Fig. 11. Temperature variation at different altitudes in Beijing during January 12-15，2015 at 0：00

Fig. 12. Concentration of pollutant gas and planetary boundary layer height from January 11-17，2015

Fig. 13. Linear fitting chart of PM2.5 and NO₂，CO on January 11-17，2015