Progress in Unraveling Atmospheric New Particle Formation and Growth Across the Arctic

New particle formation (NPF) and growth can be an important source of cloud condensation nuclei for the Arctic atmosphere, where cloud formation is sensitive to their availability. Low‐level clouds influence the Arctic energy budget, and likely contribute to amplified Arctic warming. Molecular information of NPF is rarely reported, despite its importance to determine sources of condensing vapors and nucleation mechanisms. Beck et al. (2020, https://doi.org/10.1029/2020gl091334) shed light on the complexity of NPF and growth at two Arctic locations. They reveal that chemical drivers and sources are diverse across the Arctic. This advance in knowledge calls for similar studies throughout all seasons and in various Arctic environments to obtain a more systematic understanding of NPF and growth. Plain Language Summary Atmospheric particles can be formed from gaseous vapors, a process called new particle formation (NPF). These and other vapors further condense on the newly formed particles, growing them large enough to become cloud condensation nuclei (CCN), which are essential for cloud formation. The addition of CCN from NPF is particularly important in the summertime Arctic, where the nuclei numbers are generally low, even so low that cloud formation can be inhibited. Low elevation atmospheric clouds in the Arctic are important because they control the surface energy budget. The study of Beck et al. (2020, https://doi.org/10.1029/2020gl091334) investigates in detail the sources and chemical mechanisms of NPF on Svalbard and in northern Greenland. The results show that there are many different gases, which contribute to NPF. The specific contribution and processes are a question of season and environmental properties such as phytoplankton, sea ice, and snow presence or absence. These results, together with other recent studies, now provide a more complete picture of the complexity and diversity of Arctic NPF. However, despite the new insights into the chemistry, the contribution of newly formed particles to cloud formation remains poorly quantified. Key Points Arctic new particle formation (NPF) involves a large variety of chemical species varying by location and season NPF and growth are observed throughout all seasons with enhancement when solar radiation is stronger A molecular‐level understanding of nucleation across the Arctic is still missing, and future studies should focus on filling this gap