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PM1 UNDER THE MICROSCOPE: MULTI-ANNUAL AEROSOL OPTICAL PROPERTIES AND SIZE DISTIRBUTION OBSERVATION AT PERI-URBAN ATMOSPHERIC SITE ATOLL
Suchánková, Lenka ; Bourrianne, E. ; De Fillipi, R. ; De Brito, J. F. ; Riffault, V. ; Prokeš, Roman ; Holoubek, Ivan ; Ždímal, V. ; Crumeyrolle, S.
Atmospheric aerosols (AA) belong to short-lived climate forcers with high spatial and temporal variability. Although the radiative effects of AA are greatest on regional scales, changes in aerosol emissions can induce long-term global climate effects (Szopa et al., 2021). Thus, the measurement of aerosol properties is essential for better understanding of aerosol’s impact on health and climate. Although several international projects and platforms have been monitoring AA properties worldwide (GAW, WMO, ACTRIS, EMEP, EUCAARI, etc., Pandolfi et al., 2018), only PM10 or PM2.5 cutoff sizes have been used for measurements, and information about PM1 particles is missing. \nThe aim of this study is to present aerosol scattering properties with supporting data of absorption and particle number size distribution in PM1 in years 2018-2022 at peri-urban atmospheric site “Atmospheric Observations in LiLLE (ATOLL) in Lille, France. This study is the first to present results dedicated to aerosol scattering properties at this site.
PHYSICOCHEMICAL CHARACTERISTICS AND EVOLUTION OF AEROSOL FROM OPEN COMBUSTION OF BIOMASS DURING THE TRADITIONAL “BURNING OF THE WITCHES”
Mbengue, Saliou ; Vodička, Petr ; Komínková, Kateřina ; Schwarz, Jaroslav ; Zíková, Naděžda ; Vítková, Gabriela ; Windell, Laurence Christian ; Suchánková, Lenka ; Lhotka, Radek ; Julaha, Kajal ; Prokeš, Roman ; Šmejkalová Holubová, A. ; Ondráček, Jakub ; Ždímal, Vladimír ; Holoubek, Ivan
Open biomass burning (OBB) is a major source releasing large quantities of gaseous and particulate pollutants into the atmosphere, with global, regional and local impacts on air quality, public health and climate (Andreae, 2019, Chen et al., 2017). OBB aerosols mainly consist of carbonaceous matter, and a considerable amount of inorganic salts, which present distinctly different optical properties (Chen et al., 2017, Reid et al., 2005). In this study, we investigate the influence of OBB during the traditional Burning of the Witches (BoW), referred to in Czech as “Pálení čarodějnic”, on the physico-chemical properties of atmospheric aerosols collected at the National Atmospheric Observatory Košetice (NAOK). The BoW is a centuries-old pagan tradition very popular in the Czech Republic. Today, it is celebrated during the night from April 30 to May 1 by lighting bonfires made of woodpiles with fake witches.
ON OUR RECENT WORK IN STUDYING NEW PARTICLE FORMATION (NPF)
Kovářík, Jiří ; Špalová, Anna ; Roztočil, Petr ; Zíková, Naděžda ; Schwarz, Jaroslav ; Ždímal, Vladimír
New particle formation (NPF) is increasingly gaining attention since it emerged roughly twenty years ago as a field of interest within the aerosol science. It studies the transition process between gas phase molecules, forming clusters and eventually becoming aerosol particles. Thus, this field is a multidisciplinary one, ranging from meteorology, atmospheric chemistry and physics, all the way through physical chemistry towards chemistry and physics of aerosols. \nRecent development of instrumentation techniques allows measuring of sub-5 nm particles and molecule clusters, neutral and also charged ones. Therefore, modern analytical methods based on these measurements are often used for NPF studies.
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WATER-SOLUBLE COMPOUNDS PM2.5 AT THREE RURAL BACKGROUND SITES IN CENTRAL EUROPE DURING COLD AND WARM PERIODS
Schwarz, Jaroslav ; Vodička, Petr ; Lhotka, Radek ; Pokorná, Petra ; Zíková, Naděžda ; Ondráček, Jakub ; Aurora, S. ; Poulain, L. ; Herrmann, H. ; Ždímal, Vladimír
Ion chromatography (IC) was used to characterize water soluble compounds in PM2.5 during winter and summer campaigns at three rural sites in Central Europe in 12-hour (day/night) time resolution. Concentrations of biomass combustion aerosolsdoubled from Melpitz to Košetice in winter, sea salt exhibited opposite behaviour. Summer exhibited higher sulphates and methane sulphonic acid in Melpitz. Day to night ratios showed higher day concentrations for phosphates and compounds connected to fungal spores and bacteria, while higher night concentrations were connected to wood combustion. Ventilation index was used as an approximate measure to distinguish local and long range transported aerosols. Biomass combustion products were identified as the \nmajority of local aerosols, while sea salt as long range transported one.
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TRACERS OF ANTHROPOGENIC AND BIOGENIC SOURCES OF ORGANIC AEROSOL IN THE PM1 FRACTION AT THE KOŠETICE BACKGROUND STATION
Vodička, Petr ; Kawamura, K. ; Deshmukh, D.K. ; Pokorná, Petra ; Schwarz, Jaroslav ; Ždímal, Vladimír
In this study, we have examined in detail the seasonal changes in the concentration of sugars, dicarboxylic acids and their oxidation precursors in fine aerosol at a rural Central European background site. The aim of the study was to identify typical tracers for different sources of organic aerosol and to determine their contributions to organic PM1.We found a clear difference between winter and summer PM1 aerosol composition at the molecular level. Subsequently, we identified two biogenic factors (dominant in summer), two anthropogenic factors (major contribution in winter) and one background factor.\nMore details could be found in Vodička et. al (2023).
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SUBMICRON AEROSOL AT TWO URBAN STATIONS IN PRAGUE
Pokorná, Petra ; Zíková, Naděžda ; Vodička, Petr ; Lhotka, Radek ; Ondráček, Jakub ; Schwarz, Jaroslav ; Ždímal, Vladimír ; Hopke, P.
The aim of this work was to determine the submicron aerosol dynamics, chemical compositions, and origins at two sites in Prague based on the particle number size distribution (PNSD) and chemical composition of 2/12/24h atmospheric aerosol samples (PM1) collected in parallel for half-year/within two seasons at two urban sites (suburban – Suchdol and traffic – Vršovice). Chemical analysis of PM1 for carbon (elemental, equivalent black – eBC and organic) by thermo-optical method and for water-soluble inorganic ions by IC was performed. For most months, both number and mass median \nconcentrations based on the SMPS data differed. Higher eBC concentrations were measured in Vršovice however eBC concentrations showed good correlation (r=0.80, yintercept=0) at the two stations. Higher average PM1 at the traffic site in summer and at the suburban site in winter, and seasonal differences in ionic PM1 composition reflected the seasonality of the local sources. Nevertheless, there were no statistically significant differences in PM1 concentration and ionic composition between the sites.
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INFLUENCE OF RESPIRATORY TRACT CONDITIONS ON PARTICLE SIZE DISTRIBUTIONS GENERATED BY COMMERCIALLY AVAILABLE INHALERS
Mašková, Ludmila ; Ždímal, Vladimír ; Ondráček, Jakub
Pressurized metered dose inhalers (MDI) and dry powder inhalers (DPI) are an integral part of the treatment of lung diseases such as asthma and chronic obstructive pulmonary disease (COPD) (Vichrow et al., 2008). An important characteristic of particles dosed by MDI and DPI is particle size distribution (PSD) (Byron, 1990). This may vary depending on the formulation, but also on the temperature and relative humidity (RH) changes during the transport from the inhaler to the human respiratory tract. The aim of this study was to determine the influence of RH and inspiratory flow rates on the PSD\ncharacteristics and predict deposition efficiency of inhalable particles in the lungs.
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HIGHLY-TIME RESOLVED ELEMENTAL SOURCE APPORTIONMENT OF PM2.5 AT AN URBAN TRAFFIC SITE IN PRAGUE
Windell, Laurence Christian ; Pokorná, Petra ; Ondráček, Jakub ; Schwarz, Jaroslav ; Lhotka, Radek ; Vodička, Petr ; Zíková, Naděžda ; Hopke, P.K. ; Ždímal, Vladimír
This work aims to quantify metal emissions from traffic at an urban traffic site in Prague, Czech Republic, identify key tracers of emissions, and investigate exhaust and non-exhaust emissions observable in fine particulate matter (PM2.5). This project signifies the first high-time resolution elemental analysis of Prague aerosols.
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PM1 UNDER THE MICROSCOPE: MULTI-ANNUAL AEROSOL OPTICAL PROPERTIES AND SIZE DISTIRBUTION OBSERVATION AT PERI-URBAN ATMOSPHERIC SITE ATOLL
Suchánková, Lenka ; Bourrianne, E. ; De Fillipi, R. ; De Brito, J.F. ; Riffault, V. ; Prokeš, R. ; Holoubek, I. ; Ždímal, Vladimír ; Crumeyrolle, S.
Atmospheric aerosols (AA) belong to short-lived climate forcers with high spatial and temporal variability. Although the radiative effects of AA are greatest on regional scales, changes in aerosol emissions can induce long-term global climate effects (Szopa et al., 2021). Thus, the measurement of aerosol properties is essential for better understanding of aerosol’s impact on health and climate. Although several international projects and platforms have been monitoring AA properties worldwide (GAW, WMO, ACTRIS, EMEP, EUCAARI, etc., Pandolfi et al., 2018), only PM10 or PM2.5 cutoff sizes have been used for measurements, and information about PM1 particles is missing. The aim of this study is to present aerosol scattering properties with supporting data of absorption and particle number size distribution in PM1 in years 2018-2022 at peri-urban atmospheric site Atmospheric Observations in LiLLE (ATOLL) in Lille, France. This study is the first to present results dedicated to aerosol scattering properties at this site.
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DRONE-BASED VERTICAL MEASUREMENTS OF BLACK CARBON AEROSOLS AT A RURAL BACKGROUND AND AN URBAN SITE
Julaha, Kajal ; Zíková, Naděžda ; Ždímal, Vladimír
Black Carbon (BC) aerosols are primary particles emitted into the atmosphere as a by-product of incomplete combustion processes. BC absorbs solar radiation and altersthe radiation budget of the Earth(Bond et al., 2013). The radiative properties of BC heavily depend on its vertical profiles(Haywood and Ramaswamy, 1998). For example, BC in the free troposphere can enhance its radiative forcing by trapping energy emitted from lower cloud layers. \nThe modeling-based studies on BC vertical distribution are particularly poor (Chen et al., 2022), creating a need to measure the vertical distribution of BC on a regional scale,from areas characterized by anthropogenic emissions from the ground to those characterized by long-range transport(Ramana et al., 2010). Among all the other methods, drones have recently gained popularity because of their high-cost efficiency, flexibility, and mobility. Besides comparing BC aerosol vertical distribution at an urban and a regional background site, this study also calibrates drone measurements using a 230-meter tower.
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