Identificazione degli eventi di combustione da biomassa tramite lo studio di parametri ottici e retro-traiettorie nel decennio 2010-2020 a Ny-Ålesund, Svalbard

Aerosol optical properties describe the ability of aerosols to scatter and absorb radiation at different wavelengths, with direct effects on Earth’s radiation balance and indirect effects on cloud formation processes. In this work we used the data from the Gruvebadet Aerosol Laboratory located nearby the Norwegian village of Ny-Ålesund, in the Svalbard archipelago, and managed by the National Research Council of Italy. This structure is equipped with several instruments for measurements of aerosol chemical, physical and optical properties: in particular we used the scattering coefficient values (Bsca) at 530nm obtained with an M903 Nephelometer, and absorbing coefficients values at three different wavelengths (467nm, 530nm and 660nm) measured by a Particle Soot Absorbtion Photometer (PSAP), to derive intensive coefficients such as single scattering albedo (SSA) and absorption Ångström exponent (AAE). The results were used for the identification of biomass burning events during the period from January 2010 to April 2020. Thanks to aerosol optical coefficients we were able to identify 64 probable biomass burning events, all included between March and September and especially in the summer months; then we used the HYSPLIT model developed by National Oceanic and Atmospheric Administration (NOAA), which is a complete system for computing simple air particle trajectories, to identify the areas of origin of the combustion particles, carried by the air masses within 5 days of their arrival at the atmospheric station of Ny-Ålesund. Lastly we generated images using the Terra Satellite, developed by NASA and launched on December 1999 at an altitude of 705 km, which is able to detect thermal anomalies due to fires, to confirm or deny each of the above mentioned 64 events.