Aerosols as Transport Vehicles of Persistent Pollutants
AbstractAerosol particles belong to the most important constituents of the Earth’s atmosphere. Cloud formation and cloud properties strongly depend on the amount and the type of atmospheric aerosol particles. By scattering and absorbing solar radiation they have a large impact on the global radiation budget and locally on the visibility. Finally, they consist of various chemical compounds including harmful or even toxic substances. The atmospheric lifetime of aerosols strongly depends on meteorological conditions. On the one hand, they are efficiently washed out during rain events. On the other hand they accumulate in the atmosphere under dry conditions and they can be transported over long distances, particularly if they have been mixed into higher altitudes before. Furthermore persistent pollutants like lead and other heavy metals, polyaromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are often bound to these particles and are transported with them. Their regional distribution and deposition can only be understood together with the knowledge about atmospheric aerosol particles.