Experimental simulation of the influence of aerosols on atmospheric chemistry.

Aspects of the source strenghts, formation, evaporation and transformation of the tropospheric aerosol are reviewed, including the impact on the homogeneous gas phase chemistry. An aerosol smog chamber technique is employed to investigate the photochemical conversion of trace gases under irradiation by a solar simulator with tropospheric uv intensity distribution with special regard to the impact of aerosols. Heterogeneous atmospheric photochemistry can be simulated experimentally, since the chamber is optimized for long enclosure times of aerosols. Realistic trace gas concentrations are employed in the presence of aerosols The observed concentration time profiles are compared to observations in the absence of aerosols and are interpreted with respect to the active species involved in the conversions.