The Arctic has changed at a faster rate than the rest of the planet. Clouds impact the surface energy budget and, thus, the melting or growth of land- and ocean-based ice. Many Arctic clouds are “mixed phase,” consisting of both ice and liquid particles simultaneously. Correctly predicting the partitioning of mass and transitions between these two phases is vital for understanding cloud impacts on Arctic climate. Why? Because ice particles and liquid droplets scatter and absorb solar and infrared energy in substantially different ways. A team found that the large-scale motion of air masses that have different aerosol concentrations and humidity is a major influence on the clouds’ phase. Also important were smaller-scale processes that influenced how long an ice particle stayed lofted in the cloud.