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Black carbon and ionic species in the Arctic aerosol.
Previous studies on Arctic aerosol characteristics have shown a pronounced winter-spring maximum and summer-autumn minimum in aerosol concentration. Measurements of black carbon concentration in the atmospheric aerosol were obtained by means of an aethalometer at the Zeppelinfjellet station Ny-¿lesund, Svalbard. Simultaneous 24 hour measurements of the concentration of key aerosol species like sulphate, ammonium and nitrate together with sulphur dioxide, conducted by NILU are presented and discussed in order to evaluate the transport processes governing their presence in the High Arctic. Large variations are seen to be superimposed on an overall trend that apparently exhibits higher values in winter than in late summer. Back trajectory analysis of the airmasses arriving at Zeppelin station, reveals that enhanced concentrations observed for black carbon and sulphate are associated with long range transport of polluted air from Eurasia. Black carbon, sulphur dioxide and sulphate concentrations are correlated well. Nitrate and ammonium display a rather poor association with the above species and between each other.