Multi year sun-photometer measurements for aerosol characterization in a Central Mediterranean site

► Measurements of aerosol optical depth (AOD) and Ångstrom coefficient (α) were analyzed. ► Cluster analysis in the AOD-α space allowed us to distinguish four aerosol typologies. ► Back-trajectories and model analyses allowed us to identify four aerosol classes. ► A comparative analysis of cluster results and aerosol classification was carried out. ► The influence of the different aerosol types on PM1 measurements on the ground was studied.