Study on variational aerosol fields over Beijing and its adjoining areas derived from Terra-MODIS and ground sunphotometer observation

This paper presents a comprehensive observation technique on derived aerosols data from mobile sunphotometer graph and Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) observation. Research results suggest that after being treated by the variational technique with respect to sunphotometer observations, the Terra-MODIS remote sensing aerosol data are remarkably improved, thus for the first time revealing features of the influence of aerosols and pollution emissions of Beijing and its adjoining areas (Hebei, Shandong, etc. provinces). The regional impact features of aerosols are related with the peripheral U-shape topography of Beijing. Analyses with Hybrid Single Particle Lagrangian Integrated Trajectory model (HYSPLIT-4) and meteorological data in the case studied confirm the pollutants diffusion process along the trajectory from the sources in the south-west region, and the regional aerosol impact features.