This session invites papers on all aspects of short-lived pollutants in the polar regions, addressing their sources both within and outside the polar regions, their transport to and within the polar regions, their chemistry, and their impact in the Arctic and Antarctic on air quality, radiative forcing, and climate. It will also cover processes at the interface between the atmosphere and the snow/ice surface and processes in the ice/snow as relevant for climate. Papers from recent field campaigns in the framework of the International Polar Year (POLARCAT, OASIS, AICI, etc.) are particularly welcome.