For a two year period daily samples of selected trace gases (nitric acid, sulfur dioxide and ammonia) and aerosol compounds (sulfate, nitrate, oxalate and ammonium) are determined with filter packs at the Sonnblick Observatory. The measurements will be used to identify the seasonal cycles of the selected trace gases and aerosol compounds at the 3 km level above Central Europe. Especially during the cold season previous measurements showed that samples collected at the Observatory represent free tropospheric air masses. Together with wet deposition measurements carried out at the site scavenging parameters are calculated.