Aerosol Biogeochemical cycles, Sources and TRansport processes in the climate-sensitive ArCTic (ABSTRACT) - RIS 3693 - Gruvebadet Atmospheric Laboratory Project

The general aim of the project is to obtain a better knowledge of the complex processes characterizing the atmospheric BL and the sea-atmosphere exchanges in the Arctic region and new information about the feedback processes of the polar climate system to ultimately improve the model settings and to reduce the uncertainty on future scenarios. To this purpose, thanks to the funding granted by two MIUR-PRIN Projects (PRIN 2007"Dirigibile Italia" and PRIN 2009 "Arctica" - Scientific Responsible Prof. Udisti, University of Florence), a well equipped observatory for the study of the chemical and physical properties of the aerosol was set up at Gruvebadet (about 1 km south of Ny Ålesund village). Such an observatory has become the reference facility for the research on atmospheric aerosol carried out at Ny Ålesund by Italian and foreign research groups. An ensemble of samplings and direct measurements of particulate matter has been active since 2010 and it is still ongoing, all through the opening period of the CNR Base "Dirigibile Italia" (typically Feb - Sep) and for the first time also during winter, in 2018/19. The main tasks of the activities run at Gruvebadet within the present project are to highlight and apportion as reliably as possible the natural and anthropic sources and transport processes affecting aerosol by the determination of chemical proxies (ion and elemental composition, including trace metals; carbonaceous fractions as Elemental and Organic Carbon - EC/OC) on the collected samples and by continuous size distribution measurements. As concerning aerosol samplings devoted to chemical characterization, a number of sampling devices have been used, to collect bulk (PM10) and size-segregated (4-stage, 12-stage) aerosol with different time resolution (1-7 days) and on a different sampling material (Teflon, quartz, polycarbonate) as function of the targeted chemical species. The analytical methods used to measure the selected chemical species (IC, ICP-AES, ICP-MS, PIXE, Thermo-Optical Analyzer) were carefully optimized for sensitivity and reproducibility in order to achieve reliable data. During specific periods, natural radioactivity of Rn progeny was also measured by means of a PBL mixing monitor, to study the relation between radioactivity and the mixing state of the lower atmosphere.