We aim at better understanding of climate forcing caused by aerosol particles through their modification of Arctic low level clouds. At Zeppelin Observatory at Svalbard (78 degrees North) we will study aerosol and cloud properties in-situ. The station is located at about 500 m altitude and often surrounded by clouds. By letting the clouds engulf the station we can study the cloud microphysical properties, and relate variations in these with observed aerosol characteristics. The advantage of doing this study at an elevated station versus other platforms is that it is very cost effective, and allows us to achieve temporal coverage on seasonal basis. Cloud microphysical observations will be tied together with aerosol physico-chemical properties, cloud residual properties, broadband radiation fluxes and cloud remote sensing.