Tracing natural, anthropogenic, and biomass burning contributions to Arctic aerosol combining daily chemical characterization and receptor modeling analysis

Daily PM10 samples were collected at Ny Ålesund (Svalbard Islands, Norway) from February to October 2015 and analyzed using a multi-technique approach, including ion chromatography (IC), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Particle Induced X-ray Emission (PIXE), and thermo-optical analysis (TOA). This dataset allowed for the characterization of a wide range of chemical species, including major ions, organic and elemental carbon, and over 40 elements, despite the extremely low atmospheric concentrations typical of this remote Arctic site (daily PM10 rarely exceeded 6 μg m−3, with an overall maximum of 16 μg m−3). The high temporal resolution and the large number of samples allowed the investigation of seasonal patterns and the identification of aerosol sources using the Positive Matrix Factorization (PMF) receptor model and the Potential Source Contribution Function (PSCF) to analyze of the back-trajectories. Seven distinct sources were identified: biogenic, sulphate, sea salt, combustion, nitrate, crustal, and anthropogenic. It was seen that the sampling site is mainly affected by the local natural sources; marine biogenic emissions show a strong seasonal signal linked to sunlight availability; anthropogenic sources, although less frequent, were significant during the Arctic Haze period and included long-range transported pollution from lower latitudes and the formation of secondary aerosols; episodic but intense contributions from biomass burning originating from wildfires in North America or Siberia occasionally became the dominant component of Arctic aerosol. These findings highlight the complex interplay between local natural emissions and long-range transported pollution in shaping the Arctic aerosol composition.