Year-round optical properties of atmospheric mineral dust particles at Dome C (East Antarctica): radiative and paleoclimatic implications

We present preliminary results from the project OPTAIR, aimed to study the optical properties of airborne particles at Concordia Station, on the East Antarctic plateau, and to assess the relationship among the optical properties of particles suspended in air and deposited by the snow. Light scattering data from single particles are collected continuously by a permanent device installed in November 2018, operating the novel Single Particle Extinction and Scattering method and some traditional scattering measurements. Data are put in correlation with LIDAR measurements, with the aim to assess the impact on past and present climate. Results from the Antarctic season 2019 will be presented, showing clear evidence of remarkable changes in the amount of particles, size and optical properties across the year. In particular, about one third of the total cumulative dust particles accumulated in one year is advected during fast dust-rich air mass subsidence events lasting a few hours. This feature is of major importance to glaciological studies based on integrated, multi-annual snow and ice samples.