Vertical observations of aerosol properties in the Arctic, Antarctic and Alpine atmospheric boundary layers with a tethered balloon

Information on vertical profiles of aerosols in the lowermost kilometer of the atmosphere is still scarce in general, and particularly in polar regions and complex terrain due to observational limitations. However, the vertical distribution of various aerosol properties, such as the particle number size distributions, are essential climate variables, because aerosols influence Earth’s radiation budget and their vertical position in the atmosphere matters. Specifically for aerosol-cloud interactions, the presence and properties of particles able to act as cloud condensation nuclei and ice nucleating particles at cloud level, is critical information. With this data descriptor we aim to start filling the observational gaps systematically, and introduce datasets of vertical aerosol properties from nearly 300 tethered balloon flights between 2022 and 2025 in the Arctic, Antarctica and alpine terrain in Europe. Flights up to 900 m above ground describe various boundary layer conditions throughout all seasons. We describe the processing from raw to level 2 data, provide processing and quick look codes, and give examples of how data may be used and analyzed by the community. All data and code are openly accessible.