Effect of new particle formation (NPF) on cloud condensation nuclei (CCN) in the Arctic atmosphere

Abstract

Few studies have investigated the impact of new particle formation (NPF) on cloud condensation nuclei (CCN) in the remote Arctic, and none have elucidated the relationship between NPF and CCN production. To address this knowledge gap, we conducted continuous measurements of the number size distribution of particles ranging from 3 to 60 nm and CCN number concentrations in the Arctic at Mount Zeppelin, Ny Ålesund, Svalbard, from January 2018 to December 2019. Throughout the two-year period, a total of 160 new particle formation (NPF) events were detected. Out of these events, it was analyzed 58 where both NPF and CCN data were available. It presented and discussed two cases of CCN enhancement during NPF events: (1) Case 1, (2) Case 2. By conducting cluster air mass back trajectory analysis, air masses associated with these events originated from various regions, including the ocean (n = 28), followed by multi (ocean and local) (n = 22), sea ice regions (n = 4), and others (n = 4). The findings indicate that the oxidation of oceanic biogenic precursors, specifically dimethyl sulfide (DMS), is likely a significant factor in NPF events originating from the ocean. Additionally, the release of halogen compounds from ice-covered areas may contribute to NPF events in sea ice regions. Additionally, local sources from Mount Zeppelin were found to impact aerosol production. Among the 58 analyzed NPF events, 30 cases were characterized by a simultaneous increase in the CCN concentration by 2 – 370% (median 128%) during NPF events. In the rest, there was no significant difference in the frequency of increase or decrease CCN number concentration during NPF events. Nevertheless, Arctic NPF events were found to contribute significantly to CCN sizes, which could be attributed to particles originating from different sources with distinct physical characteristics and biogenic emissions within and around the Arctic region.