Clouds regulate radiative and precipitation fluxes in polar regions, and thus control fundamental aspects of the climate system such as energy budgets, air-sea exchange, and sea level. Cloud-aerosol interactions influence polar cloud radiative impacts and precipitation efficiencies. Polar clouds, precipitation, and aerosol processes are changing in a warming world and new observations and model simulations are supporting and challenging existing paradigms. Sample topics based on observational and/or modeling studies for this session include: How do polar clouds influence radiative fluxes over sea ice and ice sheets? How much precipitation falls in polar regions? What processes control polar cloud-aerosol-precipitation interactions? What are the sources of aerosols, especially cloud condensation nuclei and ice nuclei, at high latitudes? What is the importance of super-cooled liquid cloud water for the climate system? In sum, presentations on all aspects of polar clouds, precipitation, and aerosols at high latitudes are solicited for this session.