Although remarkable progress has been made in recent decades in the field of aerosol, cloud, turbulence and radiation processes and their complex interplay, still not all aspects are understood with sufficient accuracy. This is especially true for processes at the smallest scales.

The Azores have been identified for many decades as a suitable location to study all these aspects, because this place is remote and yet offers good logistics. The archipelago is located at the boundary between the mid-latitudes and the trade wind regime, and thus in the transition between shallow cumulus convection and stratocumulus, providing a wide range of cloud types to study. Although located in the middle of the North Atlantic, the aerosol load exhibits remarkable diversity depending on the synoptic pattern, and advection from North America, Europe, or the southern part of the Atlantic leads to contrasting aerosol situations.

In July 2017, we deployed the helicopter-borne ACTOS and SMART-Helios payloads on Graciosa for a three-week period to measure high-resolution cloud, aerosol, and radiation properties. The airborne observations were accompanied by remote sensing at the ENA station at Graciosa airport and permanently ongoing aerosol observations at Mt. Pico volcano (2300 m a.s.l.) and the ENA station.

In this talk I will give an overview of the different topics currently being worked on by different groups and provide preliminary results.