The Arctic is a hot spot for climate change with potentially large consequences on a global scale. Aerosols, including bioaerosols, are important players in regulating the heat balance through direct interaction with sunlight and indirectly, through cloud formation. Airborne bacteria are key bioaerosols as some species produce the most potent ice nucleating proteins which are implicated in the formation of ice in clouds. Little is known about the numbers and dynamics of airborne bacteria in the Arctic and even less on a seasonal basis. We collected samples of aerosol and wet deposition in spring 2015 and summer 2016, at the Villum Research Station in Northeast Greenland. We used amplicon sequencing and qPCR targeting the 16S rRNA genes to assess the quantities and composition of the total and active bacterial community. We found a clear seasonal variation in the atmospheric bacterial community, which is likely due to variable sources and meteorology. In early spring, the atmospheric bacterial community was dominated by taxa originating from temperate and Sub-Arctic regions and arriving at the sampling site through long-range transport of air masses. In late spring, the long-range transport ceased, and the local sources were weak resulting in low bacterial concentrations. In summer, the air bacterial community was confined to local sources such as soil, plant material and melting sea-ice. In spring, we found that aerosolized and deposited Cyanobacteria had a high activity potential, implying their activity in the atmosphere or in surface snow. We observed a very efficient washout of the aerosolized bacterial cells during a snowstorm, which was followed by very low concentrations of bacteria in the atmosphere during the consecutive 4 weeks. We suggest that this is because long-range air mass transport is less prominent, leaving aerosolization from ice and snow as the only available sources for a new airborne bacterial community to re-establish. This is supported by observed changes in the chemical composition of aerosols. Overall, we show how biological aerosol composition in the high Arctic varies on a seasonal scale, identify their potential sources, demonstrate how their community sizes varies in time, investigate their diversity and determine their activity potential.