Ground based in situ observations of filter_1pack at Janiskoski (RU0001R). These measurements are gathered as a part of the following projects AMAP, EMEP and they are stored in the EBAS database (http://ebas.nilu.no/). Parameters measured are: nitrate in aerosol (mass_concentration_of_nitrate_expressed_as_nitrogen_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), sum_ammonia_and_ammonium in air+aerosol (mass_concentration_of_sum_ammonia_and_ammonium_in_aerosol)