Zeppelin-led study on the onset of new particle formation in the planetary boundary layer

In summer 2012 we had a campaign in Po Valley, Italy (urban background), and in spring 2013 a similar campaign took place in Hyytiala, Finland (rural background). Our study consists of three case studies of airborne and ground-based measurements of ion and particle size distribution from similar to 1 nm.

The airborne measurements were performed using a Zeppelin inside the boundary layer up to 1000m altitude. Our observations show the onset of regional NPF and the subsequent growth of the aerosol particles happening almost uniformly inside the mixed layer (ML) in both locations. However, in Hyytiala we noticed local enhancement in the intensity of NPF caused by mesoscale boundary layer (BL) dynamics.