Suchergebnisse

PM10 source apportionment was performed by positive matrix factorization (PMF) using specific primary and secondary organic molecular markers on samples collected over a one year period (2013) in Grenoble and at the SIRTA station. This station represents the suburban background air quality conditions of the Paris area (25 km SW from Paris city center) during an intense PM pollution event in March 2015 (PM10 > 50 μg m-3 for several days). Results provided a 9- and 11-factor optimum solution, including sources rarely apportioned such as two types of primary biogenic organic aerosols (fungal spores and plant debris), as well as specific biogenic and anthropogenic secondary organic aerosols (SOA). These sources were identified thanks to the use of key organic markers namely polyols, odd number higher alkanes, and several SOA markers related to the oxidation of isoprene, α-pinene, toluene polycyclic aromatic hydrocarbons (PAHs) and phenolic compounds. Findings of this work demonstrate that the speciation of the organic aerosol fraction and the input of specific molecular markers into source-receptor model are a powerful tool to discriminate OA sources and to get a better understanding of PM origins. ; La pollution due aux particules (aérosols, PM) présentes dans l'air ambiant est une problématique sanitaire primordiale. La connaissance et l'évaluation de leurs sources sont un enjeu majeur en termes de politiques de gestion de la qualité de l'air. Les travaux menés par l'Ineris, cofinancés par le LCSQA, ont permis de montrer qu'à travers une spéciation fine de la fraction organique de l'aérosol (aérosol organique, AO), et par la mesure de composés clés dits « marqueurs », une évaluation approfondie des sources des particules, incluant des sources primaires ou secondaires généralement non résolues, est réalisable.

PM10 source apportionment was performed by positive matrix factorization (PMF) using specific primary and secondary organic molecular markers on samples collected over a one year period (2013) in Grenoble and at the SIRTA station. This station represents the suburban background air quality conditions of the Paris area (25 km SW from Paris city center) during an intense PM pollution event in March 2015 (PM10 > 50 μg m-3 for several days). Results provided a 9- and 11-factor optimum solution, including sources rarely apportioned such as two types of primary biogenic organic aerosols (fungal spores and plant debris), as well as specific biogenic and anthropogenic secondary organic aerosols (SOA). These sources were identified thanks to the use of key organic markers namely polyols, odd number higher alkanes, and several SOA markers related to the oxidation of isoprene, α-pinene, toluene polycyclic aromatic hydrocarbons (PAHs) and phenolic compounds. Findings of this work demonstrate that the speciation of the organic aerosol fraction and the input of specific molecular markers into source-receptor model are a powerful tool to discriminate OA sources and to get a better understanding of PM origins. ; La pollution due aux particules (aérosols, PM) présentes dans l'air ambiant est une problématique sanitaire primordiale. La connaissance et l'évaluation de leurs sources sont un enjeu majeur en termes de politiques de gestion de la qualité de l'air. Les travaux menés par l'Ineris, cofinancés par le LCSQA, ont permis de montrer qu'à travers une spéciation fine de la fraction organique de l'aérosol (aérosol organique, AO), et par la mesure de composés clés dits « marqueurs », une évaluation approfondie des sources des particules, incluant des sources primaires ou secondaires généralement non résolues, est réalisable.

Atmospheric pollutants in urban areas are complex by virtue of their chemical composition and the multitude of emission sources. Nowadays, they represent various scientific, sanitary, political and societal challenges. INERIS is strongly involved in experimental research activities focused on these issues. Through the set-up of a new research observation platform in the region of Paris, the main objective of this work is to identify and comprehensively characterize processes and sources favoring aerosol pollution formation, using advanced and robust realtime analyzers (such as the Aerosol Chemical Speciation Monitor). In collaboration with LCSE, a unique dataset has been acquired at SIRTA since June 2011. Various statistical analyses already allowed for the refined assessment of the synergy between sources, chemical composition and geographical origins in the region of Paris. These dataset is available to better constrain chemical transport models. Moreover the technical expertise developed here recently allowed for the implementation of ACSM within regional air quality monitoring networks, as well as the build-up of the European calibration centre for on-line aerosol chemical monitors. ; Les particules en suspension (ou aérosols) représentent aujourd'hui la classe de polluants atmosphériques la plus préoccupante en matière de santé publique et d'impact environnemental. De par la multiplicité de leurs sources d'émissions et de leurs processus de formation, ces particules ont une composition chimique complexe encore mal connue. Par ailleurs, une meilleure maîtrise de leurs sources anthropiques est devenue un enjeu majeur de la surveillance de la qualité de l'air en Europe du fait du non-respect des valeurs limites fixées par la Directive 2008/50/CE dans nombreux États membres (dont la France) et de l'obligation qui leur est faite d'expliquer l'origine des dépassements de ces valeurs limites. En amont de ses missions d'appui au sein du Laboratoire central de surveillance de la qualité de l'air pour le ministère ...

Atmospheric pollutants in urban areas are complex by virtue of their chemical composition and the multitude of emission sources. Nowadays, they represent various scientific, sanitary, political and societal challenges. INERIS is strongly involved in experimental research activities focused on these issues. Through the set-up of a new research observation platform in the region of Paris, the main objective of this work is to identify and comprehensively characterize processes and sources favoring aerosol pollution formation, using advanced and robust realtime analyzers (such as the Aerosol Chemical Speciation Monitor). In collaboration with LCSE, a unique dataset has been acquired at SIRTA since June 2011. Various statistical analyses already allowed for the refined assessment of the synergy between sources, chemical composition and geographical origins in the region of Paris. These dataset is available to better constrain chemical transport models. Moreover the technical expertise developed here recently allowed for the implementation of ACSM within regional air quality monitoring networks, as well as the build-up of the European calibration centre for on-line aerosol chemical monitors. ; Les particules en suspension (ou aérosols) représentent aujourd'hui la classe de polluants atmosphériques la plus préoccupante en matière de santé publique et d'impact environnemental. De par la multiplicité de leurs sources d'émissions et de leurs processus de formation, ces particules ont une composition chimique complexe encore mal connue. Par ailleurs, une meilleure maîtrise de leurs sources anthropiques est devenue un enjeu majeur de la surveillance de la qualité de l'air en Europe du fait du non-respect des valeurs limites fixées par la Directive 2008/50/CE dans nombreux États membres (dont la France) et de l'obligation qui leur est faite d'expliquer l'origine des dépassements de ces valeurs limites. En amont de ses missions d'appui au sein du Laboratoire central de surveillance de la qualité de l'air pour le ministère chargé de l'Écologie, l'INERIS développe depuis plusieurs années des travaux de recherche expérimentale sur ces thématiques.

A detailed study of the nitrogen content organic compounds in PM, including source apportionment, has been performed over a one-year period (2013) in Grenoble (France) as well as at the SIRTA station, representing the suburban background air quality conditions of the Paris area, during an intense PM pollution event in March 2015 (PM10 > 50 μg m-3 for several days). For Grenoble, the results obtained indicated that concentrations of nitro-PAHs (polycyclic aromatic hydrocarbons) were affected by secondary processes in summer but also in cold period under specific conditions, allowing for significant nitrate chemistry and secondary nitro-PAH formation processes. For the SIRTA dataset, a novel methodology has been developed and applied to refine the sources of organic aerosol (OA) combining dataset from ACSM (aerosol chemical speciation monitor) mass spectra and specific primary and secondary organic molecular markers from PM10 filters. The results showed the deconvolution of 10 OA factors including 3 primary OA (POA) and 7 secondary OA (biogenic and anthropogenic SOA) factors. The developed methodology allowed the clear identification of about half of the total SOA mass (75% of OA) observed during the sampling campaign and highlighted that 4 OA factors were linked to biomass burning emission with 2 primary sources (biomass burning OA (BBOA) and oxidized POA (OPOA)) and 2 secondary ones (from the oxidation of phenolic compounds and toluene). Furthermore, nitrated anthropogenic SOA, related to the oxidation of PAHs (characterized by nitro-PAHs), toluene, and phenolic compounds (methoxy-phenols), accounted for about 12% of total OA and exhibited a clear diurnal pattern with high concentrations during the night indicating the prominent role of night-time chemistry (nitrate radical). Future studies will focus on the organonitrate aerosol fraction starting by an intercomparison exercise of ACSM instruments end 2018 led by the ACMCC within the ACTRIS network activities. ; La pollution due aux particules atmosphériques (aérosols, PM) est à l'origine d'importantes problématiques sanitaires et climatiques. La connaissance et l'évaluation de la contribution de leurs sources constituent ainsi un enjeu capital en termes de politiques de gestion de la qualité de l'air. Parmi ces particules, la fraction organique est d'un intérêt majeur notamment car elle contient des composés toxiques tels que les nitro-HAP (hydrocarbures aromatiques polycycliques) dont les effets sur la santé sont encore mal connus. De plus, ces composés organiques absorbent une partie du rayonnement solaire et ont un effet sur le bilan radiatif, dont l'importance reste mal évaluée. Les travaux menés par l'Ineris ont permis de réaliser une évaluation approfondie des sources des PM et notamment d'une partie de la fraction organique nitrée. Une meilleure connaissance de l'origine des aérosols organiques (AO), qui représentent une part importante de la masse totale des particules fines dans l'atmosphère (de 20 à 90 % dans la basse troposphère), a pu être obtenue à l'aide de marqueurs organiques moléculaires quantifiés sur des échantillons collectés in situ et par couplage avec des données de mesures en temps réel par spectrométrie de masse aérosol.

This work describes results obtained from the 2016 Aerosol Chemical Speciation Monitor (ACSM) intercomparison exercise performed at the Aerosol Chemical Monitor Calibration Center (ACMCC, France). Fifteen quadrupole ACSMs (Q_ACSM) from the European Research Infrastructure for the observation of Aerosols, Clouds and Trace gases (ACTRIS) network were calibrated using a new procedure that acquires calibration data under the same operating conditions as those used during sampling and hence gets information representative of instrument performance. The new calibration procedure notably resulted in a decrease in the spread of the measured sulfate mass concentrations, improving the reproducibility of inorganic species measurements between ACSMs as well as the consistency with co-located independent instruments. Tested calibration procedures also allowed for the investigation of artifacts in individual instruments, such as the overestimation of m/z 44 from organic aerosol. This effect was quantified by the m/z (mass-to-charge) 44 to nitrate ratio measured during ammonium nitrate calibrations, with values ranging from 0.03 to 0.26, showing that it can be significant for some instruments. The fragmentation table correction previously proposed to account for this artifact was applied to the measurements acquired during this study. For some instruments (those with high artifacts), this fragmentation table adjustment led to an "overcorrection" of the f44 (m/z 44/Org) signal. This correction based on measurements made with pure NH4NO3, assumes that the magnitude of the artifact is independent of chemical composition. Using data acquired at different NH4NO3 mixing ratios (from solutions of NH4NO3 and (NH4)2SO4) we observe that the magnitude of the artifact varies as a function of composition. Here we applied an updated correction, dependent on the ambient NO3 mass fraction, which resulted in an improved agreement in organic signal among instruments. This work illustrates the benefits of integrating new calibration procedures and artifact corrections, but also highlights the benefits of these intercomparison exercises to continue to improve our knowledge of how these instruments operate, and assist us in interpreting atmospheric chemistry. © 2019, © 2019 Author(s). Published with license by Taylor & Francis Group, LLC. ; Funding text #1 aLaboratoire de Météorologie Physique (LaMP), Aubiere, France; bInstitut National de l'Environnement Industriel et des Risques (INERIS), Verneuil-en-Halatte, France; cLaboratoire des Sciences du Climat et de l'Environnement (LSCE), CNRS-CEA-UVSQ, Gif-sur-Yvette, France; dAerodyne Research, Inc, Billerica, Massachusetts, USA; eEnvironment Energy and Water Research Center, The Cyprus Institute, Nicosia, Cyprus; fEstonian Environmental Research Center (EERC), Tallinn, Estonia; gFinnish meteorological institute (FMI), Helsinki, Finland; hIERSD, National Observatory of Athens, Athens, Greece; iDepartment of the Environment, Centre for Energy, Environment and Technology Research (CIEMAT), Madrid, Spain; jDeutscher Wetterdienst, Meteorologisches Observatorium Hohenpeißenberg, Hohenpeißenberg, Germany; kInstitute for Atmospheric and Earth System Research (INAR)/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland; lLeibniz Institute for Tropospheric Research, Leipzig, Germany; mEnvironmental Research Group, MRC-HPA Centre for Environment and Health, King's College London, London, United Kingdom; nInstitute of Environmental Assessment and Water Research (IDAEA-CSIC), Barcelona, Spain; oLaboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen PSI, Switzerland; pNational Institute of R&D for Optoelectronics (INOE), Ilfov, Romania; qProambiente S.c.r.l CNR Research Area, Bologna, Italy Funding text #2 This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 654109. The US Department of Energy Small Business Innovative Research program (award number DE-SC0017041) provided support for development of ACSM calibration procedures. CNRS, CEA, and INERIS are acknowledged for financial support of the ACMCC. The intercomparison campaign and the following data treatment have been conducted in collaboration with the French reference laboratory for air quality monitoring (LCSQA), funded by the French Ministry of Environment. COST action CA16109 Chemical On-Line cOmpoSition and Source Apportionment of fine aerosoLs COLOSSAL grant is gratefully acknowledged for the support of data workshops. M.C. Minguillón acknowledges the Ramón y Cajal fellowship awarded by the Spanish Ministry of Economy, Industry and Competitiveness. The CIEMAT participation has been partially funded by MINECO/AEI/FEDER, UE (CGL2017-85344-R and CGL2017-90884-REDT) and TIGAS-CM (Y2018/EMT- 5177) Project. PSI is grateful for financial support by the Federal Office for the Environment in Switzerland. ; Peer reviewed

This investigation presents the variability of near-surface in-situ aerosol particle light scattering measurements obtained over the past decade at 28 measuring atmospheric observatories which are part of the ACTRIS Research Infrastructure and most of them belong to the GAW network. This manuscript provides a comprehensive picture of the spatial and temporal variability of aerosol particles optical properties in Europe. ; This project has received funding from the European Union's Horizon 2020 research and 11 innovation programme under grant agreement No 654109, ACTRIS (project No. 262254), ACTRIS12 PPP (project No 739530).MAD station is co-financed by the PROACLIM ( CGL2014-52877-R) project. SMR station acknowledges BACCHUS (project No. 603445), CRAICC (project No. 26060) and Academy of Finland (project No. 3073314). UGR station is co-financed by the Spanish Ministry of Economy and Competitiveness through project CGL2016-81092-R. Measurements at Montseny and Montsec stations were supported by the MINECO (Spanish Ministry of Economy and Competitiveness) and FEDER funds under the PRISMA project (CGL2012-39623-C02/00), by the MAGRAMA (Spanish Ministry of Agriculture, Food and Environment) and by the Generalitat de Catalunya (AGAUR 2014 SGR33 and the DGQA). Measurements at Izaña were supported by AEROATLAN project (CGL2015-17 66229-P), co-funded by the Ministry of Economy and Competitiveness of Spain and the European Regional Development Fund. Station Košetice is supported by Ministry of Education, Youth and Sports of the Czech Republic within project for support of national research infrastructure ACTRIS – participation of the Czech Republic (ACTRIS-CZ – LM2015037). Measurements at Puy de Dôme were partly supported by CNRS-INSU, University Clermont- Auvergne, OPGC and the french CLAP program. PAL station acknowledges KONE Foundation, Academy of Finland (project No. 269095 and No. 296302). CHC station received support from Institut de Recherche pour le Développement (IRD) under both Jeune Equipe program attributed ...

Aerosol particles are a complex component of the atmospheric system which influence climate directly by interacting with solar radiation, and indirectly by contributing to cloud formation. The variety of their sources, as well as the multiple transformations they may undergo during their transport (including wet and dry deposition), result in significant spatial and temporal variability of their properties. Documenting this variability is essential to provide a proper representation of aerosols and cloud condensation nuclei (CCN) in climate models. Using measurements conducted in 2016 or 2017 at 62 ground-based stations around the world, this study provides the most up-to-date picture of the spatial distribution of particle number concentration (Ntot) and number size distribution (PNSD, from 39 sites). A sensitivity study was first performed to assess the impact of data availability on Ntot's annual and seasonal statistics, as well as on the analysis of its diel cycle. Thresholds of 50g% and 60g% were set at the seasonal and annual scale, respectively, for the study of the corresponding statistics, and a slightly higher coverage (75g%) was required to document the diel cycle. Although some observations are common to a majority of sites, the variety of environments characterizing these stations made it possible to highlight contrasting findings, which, among other factors, seem to be significantly related to the level of anthropogenic influence. The concentrations measured at polar sites are the lowest (g1/4g102gcm-3) and show a clear seasonality, which is also visible in the shape of the PNSD, while diel cycles are in general less evident, due notably to the absence of a regular day-night cycle in some seasons. In contrast, the concentrations characteristic of urban environments are the highest (g1/4g103-104gcm-3) and do not show pronounced seasonal variations, whereas diel cycles tend to be very regular over the year at these stations. The remaining sites, including mountain and non-urban continental and coastal stations, do not exhibit as obvious common behaviour as polar and urban sites and display, on average, intermediate Ntot (g1/4g102-103gcm-3). Particle concentrations measured at mountain sites, however, are generally lower compared to nearby lowland sites, and tend to exhibit somewhat more pronounced seasonal variations as a likely result of the strong impact of the atmospheric boundary layer (ABL) influence in connection with the topography of the sites. ABL dynamics also likely contribute to the diel cycle of Ntot observed at these stations. Based on available PNSD measurements, CCN-sized particles (considered here as either >50gnm or >100gnm) can represent from a few percent to almost all of Ntot, corresponding to seasonal medians on the order of g1/4g10 to 1000gcm-3, with seasonal patterns and a hierarchy of the site types broadly similar to those observed for Ntot. Overall, this work illustrates the importance of in situ measurements, in particular for the study of aerosol physical properties, and thus strongly supports the development of a broad global network of near surface observatories to increase and homogenize the spatial coverage of the measurements, and guarantee as well data availability and quality. The results of this study also provide a valuable, freely available and easy to use support for model comparison and validation, with the ultimate goal of contributing to improvement of the representation of aerosol-cloud interactions in models, and, therefore, of the evaluation of the impact of aerosol particles on climate. ; NOAA base funding supports the observatories BRW, BND, MLO, SMO, SPO and THD, where efforts of the dedicated observatory staff and of programmer Derek Hageman are appreciated. BRW observations are also supported in part by the Atmospheric Radiation Measurement (ARM) user facility, a US Department of Energy (DOE) Office of Science user facility managed by the Biological and Environmental Research programme. Measurements at Welgegund are supported by North-West University, the University of Helsinki and the Finnish Meteorological Institute. This publication also forms part of the output of the Biogeochemistry Research Infrastructure Platform (BIOGRIP) of the Department of Science and Innovation of South Africa. Pallas and SMEAR II are grateful for the support of the Academy of Finland Centre of Excellence programme (project no. 272041), the Academy of Finland project Greenhouse gas, aerosol and albedo variations in the changing Arctic (project no. 269095), and the Novel Assessment of Black Carbon in the Eurasian Arctic: From Historical Concentrations and Sources to Future Climate Impacts (NABCEA, project no. 296302). Aerosol measurements at Anmyeon-do were supported by the Korea Meteorological Administration Research and Development Program "Development of Monitoring and Analysis Techniques for Atmospheric Composition in Korea" under grant KMA2018-00522. Measurements at Gosan were supported by the National Research Foundation of Korea (2017R1D1A1B06032548) and the Korea Meteorological Administration Research and Development Program under grant KMI2018-01111. The Lulin station is operated under the grants funded by the Taiwan Environmental Protection Administration. WLG is supported by the China Meteorological Administration, where efforts of the dedicated observatory staff are appreciated. Sites PDM, PUY, GIF, CHC and RUN are partially operated with the support of CNRS-INSU under the long-term observation programme and the French Ministry for Research under the ACTRIS-FR national research infrastructure. PDM and GIF received specific support from the French Ministry of the Environment. ATMO Occitanie is mentioned for sampling operations at PDM. Measurements at SIRTA are hosted by CNRS and by the alternative energies and atomic energy commission (CEA) with additional contributions from the French Ministry of the Environment through its funding to the reference laboratory for air quality monitoring (LCSQA). PUY is grateful for support from ATMO Auvergne Rhône Alpes for sampling operations and the support from the personnel of the Observatoire de Physique du Globe de Clermont-Ferrand (OPGC). The specific support of the Institut de Recherche et Développement (IRD) in France and the Universidad Mayor de San Andrés in Bolivia support operations at CHC operations. The Steamboat Ski Resort provided logistical support and in-kind donations for SPL. The Desert Research Institute is a permittee of the Medicine Bow–Routt National Forests and an equal opportunity service provider and employer. SPL appreciates the extensive assistance of the NOAA/ESRL Federated Aerosol Network, of Ian McCubbin, site manager of SPL, and of Ty Atkins, Joe Messina, Dan Gilchrist and Maria Garcia, who provided technical assistance with the maintenance and data quality control for the aerosol instruments. SGP measurements/mentorship were supported by DOE-7F-30118 and staff on site. The Cape Grim Baseline Air Pollution Monitoring Station is grateful to the Australian Bureau of Meteorology for their long-term and continued support and all the staff from the Bureau of Meteorology and CSIRO, who have contributed to the generation of records reported here. The aerosol measurements at the Jungfraujoch were conducted with financial support from MeteoSwiss (GAW-CH aerosol monitoring programme) and from the European Union as well as the Swiss State Secretariat for Education, Research and Innovation (SERI) for the European Research Infrastructure for the observation of Aerosol, Clouds and Trace Gases (ACTRIS). The International Foundation High Altitude Research Station Jungfraujoch and Gornergrat (HFSJG) is mentioned for providing the research platform at the Jungfraujoch. The aerosol measurements at Kosetice received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement no. 654109 and from the project for support of the national research infrastructure ACTRIS – participation of the Czech Republic (ACTRIS-CZ – LM2015037) supported by the Ministry of Education, Youth and Sports of CR within National Sustainability Program I (NPU I), grant agreement no. LO1415. The measurements were also supported by ERDF "ACTRIS-CZ RI" (no. CZ.02.1.01/0.0/0.0/16_013/0001315). Measurements at the Madrid site were funded by the following projects: CRISOL (CGL2017–85344-R MINECO/AEI/FEDER, UE), TIGAS-CM (Madrid Regional Government Y2018/EMT5177), AIRTEC-CM (Madrid Regional Government P2018/EMT4329), REDMAAS2020 (RED2018-102594-T CIENCIA) and Red de Excelencia ACTRIS-ESPAÑA (CGL2017-90884-REDT). Measurements at Montsec and Montseny were supported by the Spanish Ministry of Economy, Industry and Competitiveness and FEDER funds under project HOUSE (CGL2016-78594-R) and by the Generalitat de Catalunya (AGAUR 2017 SGR41 and the DGQA). Aerosol measurements at El Arenosillo Observatory are supported by the National Institute for Aerospace Technology and by different R&D projects of the Ministerio Español de Economía, Industria y Competitividad (MINECO). Aerosol measurements at UGR are supported by the Spanish Ministry of Economy and Competitiveness through projects no. CGL2016-81092-R, CGL2017-90884-REDT, RTI2018-097864-B-I00 and PGC2018-098770-B-I00 and by the Andalusia Regional Government through project no. P18-RT-3820. FKL, HAC and DEM are grateful for funding by project PANhellenic infrastructure for Atmospheric Composition and climate change (MIS 5021516), which is implemented under action Reinforcement of the Research and Innovation Infrastructure, funded by operational programme Competitiveness, Entrepreneurship and Innovation (NSRF 2014-2020) and co-financed by Greece and the European Union (European Regional Development Fund). CPC measurements at Sonnblick are supported by the Climate and Air Quality Commission of the Austrian Academy of Sciences and the office of the provincial government Salzburg, Unit 5/02. At CMN, aerosol measurements were partially supported by the Italian Ministry of Research and Education. Measurements at Birkenes II are financed by the Norwegian Environment Agency. VAV is grateful for various Swedish FORMAS, Swedish Research Council (VR) grants and the Magnus Bergvall and Märta och Erik Holmberg foundations and the Swedish EPA for making the research possible at the VAV site. NMY wishes to thank the many technicians and scientists of the Neumayer overwintering crews, whose outstanding commitment enabled continuous, high-quality aerosol records over many years. Gunter Löschau is acknowledged for his contribution to the data acquisition at ANB, DTC and DRN. Financial support This research was supported by the European Commission's Horizon 2020 Framework Programme (ACTRIS2 (grant agreement no. 654109)), the University of Helsinki, the Finnish Meteorological Institute, the Department of Science and Innovation of South Africa, the Academy of Finland Centre of Excellence programme (project no. 272041), the Academy of Finland project Greenhouse gas, aerosol and albedo variations in the changing Arctic (project no. 269095), the Novel Assessment of Black Carbon in the Eurasian Arctic: From Historical Concentrations and Sources to Future Climate Impacts (NABCEA, project no. 296302), the Korea Meteorological Administration Research and Development Program "Development of Monitoring and Analysis Techniques for Atmospheric Composition in Korea" (grant no. KMA2018-00522), the National Research Foundation of Korea (grant no. 2017R1D1A1B06032548), the Korea Meteorological Administration Research and Development Program (grant no. KMI2018-01111), the Taiwan Environmental Protection Administration, the China Meteorological Administration, the National Scientific Foundation of China (41675129, 41875147), the National Key R&D Program of the Ministry of Science and Technology of the People's Republic of China (grant no. 2016YFC0203305 and 2018YFC0213204), the Chinese Academy of Meteorological Sciences (2020KJ001), the Innovation Team for Haze-fog Observation and Forecasts of MOST and CMA, CNRS-INSU, the French Ministry for Research under the ACTRIS-FR national research infrastructure, the French Ministry of the Environment, MeteoSwiss (GAW-CH aerosol monitoring programme), the Swiss State Secretariat for Education, Research and Innovation (SERI), the Ministry of Education, Youth and Sports of CR within National Sustainability Program I (NPU I, grant no. LO1415), ERDF "ACTRISCZ RI" (grant no. CZ.02.1.01/0.0/0.0/16_013/0001315), CRISOL (CGL2017-85344-R MINECO/AEI/FEDER, UE), TIGAS-CM (Madrid Regional Government Y2018/EMT-5177), AIRTEC-CM (Madrid Regional Government P2018/EMT4329), REDMAAS2020 (RED2018-102594-T CIENCIA), Red de Excelencia ACTRIS-ESPAÑA (CGL2017-90884-REDT), the Spanish Ministry of Economy, Industry and Competitiveness, FEDER funds (project HOUSE, grant no. CGL2016-78594-R), the Generalitat de Catalunya (AGAUR 2017 SGR41 and the DGQA), the National Institute for Aerospace Technology, the Ministerio Español de Economía, Industria y Competitividad (MINECO), the Spanish Ministry of Economy and Competitiveness (projects no. CGL2016-81092-R, CGL2017-90884-REDT, RTI2018-097864-B-I00 and PGC2018-098770-B-I00), the Andalusia Regional Government (project no. P18-RT-3820), the PANhellenic infrastructure for Atmospheric Composition and climate change (MIS 5021516), Research and Innovation Infrastructure, Competitiveness, Entrepreneurship and Innovation (grant no. NSRF 2014-2020), the Italian Ministry of Research and Education, the Norwegian Environment Agency, Swedish FORMAS, the Swedish Research Council (VR), the Magnus Bergvall foundation, the Märta och Erik Holmberg foundation, and the Swedish EPA. ; Peer reviewed