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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.
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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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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INTRODUCTION TO PRAGUE AEROSOL CALIBRATION CENTER
Ondráček, Jakub ; Roztočil, Petr
In general, the PACC offers a range of services, from calibration and consulting to methodology and technical development. Furthermore, the PACC has the capacity to organize and perform training for microphysical (including optical in the near future) aerosol in-situ instrumentation. The equipment at the PACC is fully in-line with the state of-the-art aerosol instrumentation (starting from various aerosol generators for welldefined nanoparticles, reference instruments, and newly designed calibration lines) and the laboratory space is flexible for various types of instrument calibration/verification/intercomparison or testing of newly developed, cutting-edge equipment.
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Change in Size-Resolved Filtration Efficiency of Respirators after Decontamination/Disinfection Treatments
Ondráček, Jakub ; Ondráčková, Lucie ; Dřevínek, M. ; Otáhal, P. ; Vošáhlík, J.
Furthermore, during COVID pandemic many people were using the PPEs for longer time than it was suggested by the manufacturer or tried to use home-made or web \ncommunity recommended decontamination/disinfection/antiviral treatments. Such treatments may severely destroy the structure of the filtration material and alter the \nfiltration properties as compared to the original piece of the PPE and thus not protect the wearer properly against harmful particles. This work aims to estimate the change in the \nsize-resolved filtration efficiency of different respirators after application of selected decontamination/disinfection treatments.
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The impact of covid-19 restrictions on carbonaceous aerosols at rural background site: importance of vertical distribution
Mbengue, Saliou ; Vodička, Petr ; Komínková, Kateřina ; Schwarz, Jaroslav ; Zíková, Naděžda ; Prokeš, Roman ; Suchánková, Lenka ; Julaha, Kajal ; Ondráček, Jakub ; Holoubek, Ivan ; Ždímal, Vladimír
In this study, EC and OC at 4 m elevation and EC at 230 m elevation showed a similar \nseasonal pattern with higher values in winter and lower values in summer. OC, measured \nat 230 m height showed an opposite behavior with slightly higher values in spring and \nsummer, probably related to the increased contribution of secondary organic carbon \n(SOC). Concentrations were generally higher at 4 m, where there was also a better \ncorrelation between EC and OC, suggesting a greater influence of local sources near the \nsurface.
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Physicochemical Properties and Origin of PM1 Measured at a Rural Background Site
Pokorná, Petra ; Zíková, Naděžda ; Vodička, Petr ; Lhotka, Radek ; Mbengue, Saliou ; Holubová Šmejkalová, A. ; Riffault, V. ; Ondráček, Jakub ; Schwarz, Jaroslav ; Ždímal, Vladimír
This study assesses the variability of organic aerosol (OA) sources monitored at the rural background site Frýdlant. Non-refractory PM1 was evaluated in two seasons of\n2021. The positive matrix factorization with the multi-linear engine was used to determine the sources of OA at Frýdlant site, with four factors resolved both in winter and\nsummer.
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A Seven-Years Based Characterization of Aerosol Light Scattering Properties at Central European Rural Site: Variability and Source Apportionment
Suchánková, Lenka ; Mbengue, S. ; Zíková, Naděžda ; Ondráček, Jakub ; Holubová Šmejkalová, A. ; Prokeš, R. ; Holoubek, I. ; Ždímal, Vladimír
The aim of this study is to focus on the temporal variations of light-scattering properties of aerosols at a rural background site in Central Europe. The total light scattering (σsp) and backscattering (σbsp) coefficients and associated calculated optical properties such as the Ångström exponent (SAE), the backscattering ratio (b), and the asymmetry factor (g), are characterized considering different time scales (annual, seasonal, monthly, or diurnal) based on long-term measurement. The optical properties were compared with meteorological conditions (fog, cloudiness), the concentrations of gaseous pollutants such as NOx and SO2 were inspected as well as potential sources of atmospheric aerosols. In addition, radiative forcing, and the influence of other meteorological conditions (e.g., height of planetary boundary layer), chemical composition and particle size distribution at the National Atmospheric Observatory Košetice (NAOK) are being further investigated to better understand the direct effects of aerosols on the local climate.
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See also: similar author names
2 Ondráček, J.
9 Ondráček, Jan
1 Ondráček, Jaroslav
4 Ondráček, Jiří
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