Analysis of the Interaction of Aerosol Transport Layers on Local Air Quality

In this paper, the usefulness of multi-wavelength lidar measurements to study the interaction of aerosols in the PBL with long range advected aerosol plumes is presented. Lidar´s measurements are used to determine the plume angstrom exponent, which is used to differentiate smoke events from dust events, as well as partitioning the total aerosol optical depth obtained from a CIMEL sky radiometer between the PBL and the high altitude plumes. Furthermore, the correlation between the lidar derived PBL aerosol optical depth and surface PM2.5 is high, only if the optical depth from the upper level plumes is taken into account. In addition, the dynamic interaction of high altitude plumes interacting with the PBL result a dramatic rise in surface PM10 concentrations without a corresponding dramatic rise in PM2.5 concentrations. These observations strongly suggest the deposition of large particulates into the PBL which is consistent with both lidar angstrom coefficient measurements and back-trajectory analysis.