15-yr long records of aerosol and surface snow chemical composition at Dome C (High Antarctic Plateau)

The study of aerosol chemical composition in the Antarctic plateau can provide basic information on the main natural (and also anthropogenic) inputs, atmospheric reactivity, and long-range transport processes of the aerosol components. Moreover, chemical and physical processes occurring at the atmosphere-snow interface are yet not fully understood and work is needed to assess the impact of atmospheric chemistry on snow composition and to better interpret ice core records retrieved at those sites.

At this purpose, simultaneous aerosol and surface snow samplings were set up and run at Dome C station (75° 06’ S; 123° 20’ E, 3233 m a.s.l) all year-round since 2004/05 and are still ongoing through various PNRA Projects, particularly LTCPAA (2016-2020) and STEAR (2020-2023).

Aerosol and snow samples were analysed for main and trace ion markers, aiming to better constrain extent and timing of the main natural sources (sea salt, marine biogenic, mineral dust) and to detect the possible contribution of anthropic inputs (biomass burning, wildfires, local contamination). In addition, such a study might help in improving our knowledge of transport processes (free troposphere, stratosphere-troposphere exchange) and atmospheric reaction processes (such as neutralization, chemical fractionation).

A comparison with ozone measurements, carried out continuously over the same period, is also attempted, to better address the atmospheric processes involving the atmosphere-snow exchanges of N-cycle species and atmosphere oxidative properties.