The aim of this project is to investigate the processes involving mercury (Hg) at the snow-air interface in the polar regions. The dynamic exchange of Hg between the snow surface and the overlaying atmosphere in polar regions is not fully understood and not yet constrained into the one-dimensional chemistry models. This project will deeply study the snow photochemical processes affecting Hg and other compounds (such as bromine) in the spring polar snowpack. The campaign consists of performing three field experiments with different time resolution in the proximity of the Ny-Ålesund research village (Svalbard), with the aim to find possible links between surface concentrations of Hg and atmospheric, irradiance and snow conditions. The data produced within the project will be combined with the atmospheric and snowpack data available from the Ny-Ålesund research stations and used for the development of a specific chemistry model able to reproduce the chemistry of Hg at the snow-air interface, that is the final goal of the candidate’s PhD project.