Ground based in situ observations of filter_2pack at Leba (PL0004R). These measurements are gathered as a part of the following projects EMEP, GAW-WDCA, GAW-WDCRG, HELCOM and they are stored in the EBAS database (http://ebas.nilu.no/). Parameters measured are: ammonium in aerosol (mass_concentration_of_ammonium_expressed_as_nitrogen_in_dry_aerosol_particles_in _air), ammonium in aerosol (mass_concentration_of_ammonium_in_dry_aerosol_particles_in _air), chloride in aerosol (mass_concentration_of_chloride_in_dry_aerosol_particles_in _air), nitrate in aerosol (mass_concentration_of_nitrate_expressed_as_nitrogen_in_dry_aerosol_particles_in _air), nitrate in aerosol (mass_concentration_of_nitrate_in_dry_aerosol_particles_in _air), sulphate_corrected in aerosol (mass_concentration_of_sulphate_corrected_for_seaspray_expressed_as_sulphur_in_dry_aerosol_particles_in_air), sulphate_corrected in aerosol (mass_concentration_of_sulphate_corrected_for_seaspray_in_dry_aerosol_particles_in_air), sulphate_total in aerosol (mass_concentration_of_total_sulphateexpressed_as_sulphur_in_dry_aerosol_particles_in_air), sulphate_total in aerosol (mass_concentration_of_total_sulphateexpressed_as_sulphur_in_dry_aerosol_particles_in_air), sulphur_dioxide in air (mass_concentration_of_sulphur_dioxide_expressed_as_sulphur_in_air)