The aerosol size distribution was obtained combining measurements from a neutral and air ion spectrometer (NAIS) with a differential mobility particle sizer (DMPS). Merging particle size distribution (PSD) measurements from different instruments allows to extend the size range of individual instruments and obtain a more complete characterization of the aerosol population. Aerosols are important for a variety of reasons, one of the most prominent is that a sub-set of the aerosol population can act as cloud condensation nuclei (CCN) influencing cloud formation and the Earth radiative budget. The measurements reported here can be used to investigate aerosol sources and processes. Measurements were performed on the 4th deck of icebreaker Oden during August and September 2018 along the track of the expedition. The concentration is reported as dN/dlog(Dp) per cubic centimeter with a 3 minutes time resolution.