Altitude Aerosol Measurements in Central France: Seasonality, Sources and Free‐Troposphere/Boundary Layer Segregation

Abstract

Long-term and continuous measurements of aerosol chemical composition is essential to improve our understanding of the formation and transformation of aerosol particles in the atmosphere. Thanks to the recent developments of aerosol mass spectrometry, notably with the Aerosol Chemical Speciation Monitor (ACSM, Aerodyne; Fröhlich et al., 2013; Ng et al., 2011), this information can be acquired over long periods of time with minimal intervention from the user. The ACSM is a robust tool that measures aerosol chemical properties of the aerosol with time resolutions ranging from 10 to 30 min. Global long-term ACSM data sets have recently been presented in the literature, including a 6-year study near Paris (France; Petit et al., 2015; Zhang et al., 2019), a 2-year study in the megacity of Beijing (China; Sun et al., 2018), and a 5-year study from Leipzig (Germany; Poulain et al., 2020). The measurements within Europe are mostly being performed within the framework of the ACTRIS infrastructure (Aerosols, Clouds, and Trace gases Research InfraStructure), and a growing database of these measurements is available via the EBAS database (http://ebas.nilu. no/). Pluri-annuel and multi seasonal studies provide an opportunity to study how aerosol particles concentrations and chemical signature evolves over time in response to different airmass sources and atmospheric changes. This information is useful for understanding transport and aging patterns and can also be used for the validation of atmospheric models. Similar to worldwide measurements at low altitudes (Jimenez et al., 2009; Zhang et al., 2007), organic species also dominate the PM1 mass concentrations at high altitudes (Zhou et al., 2019). Fröhlich et al. (2015) at the Jungfraujoch station (JFJ, 3,580 m a.s.l), showed that organics were the dominant species, making

Seasonal Variations, Origin, and Parameterization of Ice‐Nucleating Particles at a Mountain Station in Central France

“…Furthermore, the seasonal trend in aerosol properties at PUY has previously been reported for aerosol concentrations by Farah et al. (2021), Bourcier et al. (2012), and Venzac et al.…”

“…INPs of marine origin are suspected to play an important role in cloud formation in the remote ocean environment (DeMott et al, 2016;McCluskey et al, 2018;Wilson et al, 2015), but have never been shown to be important in continental areas where terrestrial sources are considered a major contribution (Burrows et al, 2013;Huang et al, 2021). Atlantic air masses represent about 40%-50% of the air masses during the autumn and winter at PUY (Farah et al, 2018(Farah et al, , 2021.…”

In Situ Observation of Multiphase Oxidation-Driven Secondary Organic Aerosol Formation during Cloud Processing at a Mountain Site in Southern China

“…Furthermore, SOA (LO-OOA and MO-OOA) was dominant (approximately 90%) in OA, consistent with other regional studies. 42,43 The mass fraction of MO-OOA (f MO-OOA ) in cloud residual and cloud interstitial particles increased when the cloud events occurred (Figure 1) ,and it also increased with the duration of the cloud event, which might suggest clouds could promote MO-OOA formation through oxidation, especially in the cloud residuals. Notably, higher f MO-OOA values during CE4 and CE5 than during other events (i.e., CE1, CE2, and CE3) were likely attributed to more LO-OOA being further oxidized in those cloud events.…”