In-situ measurements of Saharan dust concentrations and charge over Cyprus with an uncrewed aircraft system

Mineral dust is one of the biggest contributors of particulate matter in the atmosphere, and its transport as well as atmospheric implications has been a topic of interest for the last few decades. Still, mineral dust dynamics are often not appropriately accommodated in model simulations, which require in-situ datasets for more accurate representation of dust events. In our study, the uncrewed aircraft system (UAS) of type MASC-3 was employed for measurements of meteorological parameters (potential temperature, mixing ratio and the three-dimensional wind vector at high temporal resolution), turbulent quantities, aerosol particles and space charge, during an intense dust event over Cyprus in spring, 2022. Vertical profiles up to 3000 m above sea level (a.s.l) revealed how the dust layer had peaks at 1800 and 2500 m, as well as affected the extent of the atmospheric boundary layer. The measurements from the UAS were in good agreement with remote sensing instrumentation in the vicinity of the flights, with the observations being further supported by satellite imagery and back tracking model simulations. Vertical profiles of charge were also co-related to approximated modeled one-dimensional profiles of the expected charge for the given dust concentrations. The results showed several layers of charge throughout the dust cloud’s vertical extent, most notably at its upper and lower boundaries, as anticipated from theoretical calculations. This is the first time charge measurements were made possible using a UAS, and in combination with data for dust concentrations and meteorological quantities, new insights can be discovered regarding mineral dust charge, characteristics and its interaction with the atmosphere.